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1
Kasuya, Masahiro, Andriantsoa R. Olivier, Yoko Ota, Motoaki Tojo, Hitoshi Honjo, and Ryo Fukui. "Induction of Soil Suppressiveness Against Rhizoctonia solani by Incorporation of Dried Plant Residues into Soil." Phytopathology® 96, no. 12 (December 2006): 1372–79. http://dx.doi.org/10.1094/phyto-96-1372.
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Suppressive effects of soil amendment with residues of 12 cultivars of Brassica rapa on damping-off of sugar beet were evaluated in soils infested with Rhizoctonia solani. Residues of clover and peanut were tested as noncruciferous controls. The incidence of damping-off was significantly and consistently suppressed in the soils amended with residues of clover, peanut, and B. rapa subsp. rapifera ‘Saori’, but only the volatile substance produced from water-imbibed residue of cv. Saori exhibited a distinct inhibitory effect on mycelial growth of R. solani. Nonetheless, disease suppression in such residue-amended soils was diminished or nullified when antibacterial antibiotics were applied to the soils, suggesting that proliferation of antagonistic bacteria resident to the soils were responsible for disease suppression. When the seed (pericarps) colonized by R. solani in the infested soil without residues were replanted into the soils amended with such residues, damping-off was suppressed in all cases. In contrast, when seed that had been colonized by microorganisms in the soils containing the residues were replanted into the infested soil, damping-off was not suppressed. The evidence indicates that the laimosphere, but not the spermosphere, is the site for the antagonistic microbial interaction, which is the chief principle of soil suppressiveness against Rhizoctonia damping-off.
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Dari, Linda, Ahmad ADDO, and Komla Agbeko DZISI. "Determination of Pesticide Residuals in Soil and Tomato Fruits from Two Tomato Production Areas in northern Ghana." Ghana Journal of Science, Technology and Development 6, no. 2 (March 1, 2020): 37–44. http://dx.doi.org/10.47881/167.967x.
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Tomato fruit (Lycopersicon esculentum Mill) is an important vegetable commodity in Ghana, as it is consumed daily in many households either heat-treated or without any form of heat treatments. Tomato production is a major source of income for many smallholder producers in Northern Ghana especially through dry season farming when the major supply of tomatoes from Southern Ghana is exhausted. Research conducted for the past decade confirmed the presence of pesticide residues in fruits and vegetables such as cabbage, onion, cucumber, lettuce, tomatoes, okra and pepper. The objective of this study was to identify and estimate pesticide residual levels in the soil and tomato fruits in comparison with the maximum allowable residual limits. The research was carried out in two production communities namely Doba where the “Burkina” variety is mostly grown in the Kassena Nankana East District of the Upper East Region and Bunglung where the “Wosowoso” variety is cultivated in the Savelugu/Nanton Municipality of Northern Region. Soil samples were collected for residue determination before transplanting of tomato seedlings. Matured and ripe tomato fruits were also collected for the determination of the presence and amount of pesticide residues. All soil and plant samples were analysed using high performance liquid chromatography to determine the presence of twenty-four organochlorines and thirteen organophosphate pesticide residues. From the analysis, pesticide residues were present in different variations which ranged from 0.002 – 0.033 and 0.003 – 0.022 (soils) and 0.330 – 1.187 and 0.002 – 0.088 (fruits) for organochlorines and organophosphates respectively for both communities. Levels of pesticide residues were generally above the acceptable maximum residue limits as farmer practices produced fruits with more pesticide residues since the land areas could have been predisposed with residues from previous seasons for other food crops, which could be translocated into the tomato plant and through into the fruits. The presence of pesticide residues could also be attributed to the influence of run-off and drift from other cultivated lands. For effective determination of pesticides residues in the tomato plants, it is essential to use uncontaminated soil and water to facilitate the efficient estimation of pesticide residues in tomatoes and plants in general.
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Friesen, DK, and GJ Blair. "A dual radiotracer study of transformations of organic, inorganic and plant residue phosphorus in soil in the presence and absence of plants." Soil Research 26, no. 2 (1988): 355. http://dx.doi.org/10.1071/sr9880355.
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The rates of transfer of P from plant residues added to an acid soil into various soil P pools and the rates of transfer of inorganic P from soil solution into other soil P pools were studied by simultaneous use of 32P-labelled plant matter and 33P-labelled soil in the presence and absence of growing plants. Equilibration of 33P-labelled phosphate solution added to soil reached a steady state with soil ALP and Fe-P pools within 1 day after addition. The Fe-P pool was much more stable than the A1-P pool since it was not depleted by cropping. This non-labile pool 'fixed' over 30% of the 33P added and similar amounts of the 32P released from plant residues. About 50% of the 32P from plant residues was found in inorganic P pools 11 days after addition. This rapid release was attributed to the presence of soluble inorganic P in the residues. A further 10% was released slowly over the remainder of the experiment. Cropping only marginally slowed rates of transfer of inorganic and released residue P into non-labile pools. Cropping had no effect on the rates of release of P from crop residues.
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Whalen, Joann K., Shamim Gul, Vincent Poirier, Sandra F. Yanni, Myrna J. Simpson, Joyce S. Clemente, Xiaojuan Feng, et al. "Transforming plant carbon into soil carbon: Process-level controls on carbon sequestration." Canadian Journal of Plant Science 94, no. 6 (August 2014): 1065–73. http://dx.doi.org/10.4141/cjps2013-145.
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Whalen, J. K., Gul, S., Poirier, V., Yanni, S. F., Simpson, M. J., Clemente, J. S., Feng, X., Grayston, S. J., Barker, J., Gregorich, E. G., Angers, D. A., Rochette, P. and Janzen, H. H. 2014. Transforming plant carbon into soil carbon: Process-level controls on carbon sequestration. Can. J. Plant Sci. 94: 1065–1073. Plants figure prominently in efforts to promote C sequestration in agricultural soils, and to mitigate greenhouse gas (GHG) emissions. The objective of the project was to measure the transformations of plant carbon in soil through controlled laboratory experiments, to further understand (1) root-associated CO2 and N2O production during a plant's life cycle, (2) decomposition of plant residues leading to CO2 production, and (3) stabilization and retention of undecomposed plant residues and microbial by-products in the resistant soil C fraction. Experimental plant materials included transgenic near isolines of Zea mays L. and cell wall mutants of Arabidopsis thaliana, selected for their diverse residue chemistry. Phenology, morphology and above-ground biomass affected soil respiration and N2O production in root-associated soils. Mineralization of C and N from incubated plant–soil mixtures was complemented with stable isotope tracing (13C, 15N) and 13C-phospholipid fatty acid analysis. Advanced chemical techniques such as nuclear magnetic resonance spectroscopy and physical separation (particle size and density separation) were used to track the transformations of plant C into stable soil C compounds. Conceptual models were proposed to explain how the plant residue chemistry×soil physico-chemical interaction affects C sequestration. Incorporating single gene mutations affecting lignin biosynthesis into agricultural and bioenergy crops has the potential to alter short- and long-term C cycling in agroecosystems.
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Mclaughlin, MJ, and AM Alston. "The relative contribution of plant residues and fertilizer to the phosphorus nutrition of wheat in a pasture cereal system." Soil Research 24, no. 4 (1986): 517. http://dx.doi.org/10.1071/sr9860517.
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Wheat plants (Triticum aestivum cv. Warigal) here grown in a solonised brown soil (Calcixerollic xerochrept) which had been previously cropped to medic (Medicago trunculata cv. Paraggio). The 33P-labelled medic residues and 32P-labelled monocalcium phosphate were added to the soil in factorial combination. Amounts of 31P, 32P and 33P in the wheat plants and in the soil microbial biomass were determined. Addition of residues depressed wheat dry weight, 31P and 32P uptake, while simultaneously increasing amounts of 31P and 32P incorporated into the microbial biomass. Addition of fertiliser had no effect on the proportion of plant P taken up from the residues, but significantly increased the proportion of microbial P derived from this source. The 31P held in the microbial biomass was significantly increased by both residue and fertiliser P addition, with the former having the larger effect. Of the total P applied to the soil, medic residues contributed approximately one-quarter of that supplied by the fertiliser. Of the total P in the wheat plant, medic residues supplied approximately one-fifth of that supplied by the fertiliser.
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Trong Hung, Dao, Harold Hughes, Markus Keck, and Daniela Sauer. "Rice-Residue Management Practices of Smallholder Farms in Vietnam and Their Effects on Nutrient Fluxes in the Soil-Plant System." Sustainability 11, no. 6 (March 19, 2019): 1641. http://dx.doi.org/10.3390/su11061641.
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In Vietnam, approximately 39 million tons of rice (Oryza sativa) residues accrue every year. In this study, we quantified soil nutrient balances of paddy rice fields under different crop-residue management practices in northern Vietnam. On twelve farms, we calculated nutrient balances for the four prevalent rice-residue management practices, i.e., (1) direct incorporation of rice residues into the soil, (2) application of rice-residue compost, (3) burning of rice residues on the field, and (4) the use of rice residues as fodder for livestock. Soils under practices (1) to (3) showed a positive nutrient balance, which indicates that soil fertility can be maintained under these practices and that the amounts of chemical fertilizers can be considerably reduced. If not, there is a risk of eutrophication in the surrounding surface waterbodies. Practice (4), in contrast, resulted in a negative nutrient balance, which indicates the need for returning nutrients to the soils. From our findings we conclude that knowledge about the effects of rice-residue management practices on nutrient cycles may help to optimize the use of fertilizers, resulting in a more sustainable form of agriculture.
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Jalali, Mohsen, Maryam Saeedi Lotf, and Faranak Ranjbar. "Changes in some chemical properties of saline-sodic soils over time as affected by organic residues: An incubation study." Polish Journal of Soil Science 53, no. 1 (June 22, 2020): 1. http://dx.doi.org/10.17951/pjss.2020.53.1.1.
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<p>Salinization and sodification of agricultural lands in arid and semi-arid regions of the world are two limiting factors in the crop production. This study was conducted to evaluate the effect of readily available agricultural residues on changing some chemical properties of saline-sodic soils. Wheat, potato, sunflower, and canola residues were separately added into three saline-sodic soils at a rate of 2% by weight and thoroughly mixed with soils. Control and treated soils were incubated for 168 days at a constant moisture and temperature. The pH, electrical conductivity (EC), soluble cations, available nitrate (NO3-) and phosphorous (P), cation exchange capacity (CEC), and exchangeable sodium percentage (ESP) were measured during the incubation. The EC increased in the response to the incorporation of plant residues, whereas the pH was reduced. The application of organic components in soils increased CEC and decreased ESP. The results showed that the maximum reduction in ESP was observed in the potato treatment because of the highest Ca2+ concentration. The average reduction in ESP of treated soil samples at the end of incubation followed this order: 16.1% (potato residue-treated soil) >12.7% (canola residue-treated soil) >11.1% (wheat residue-treated soil) >9.6% (sunflwer residue-treated soil). The potato residue was the most effective amendment in changing the chemical properties of saline-sodic soils in comparison with other organic residues. The results indicated that the application of organic residues had a positive impact on reducing the soil sodicity and improving the soil fertility depending on their chemical composition.</p>
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Klein, Eyal, Jaacov Katan, and Abraham Gamliel. "Soil Suppressiveness to Fusarium Disease Following Organic Amendments and Solarization." Plant Disease 95, no. 9 (September 2011): 1116–23. http://dx.doi.org/10.1094/pdis-01-11-0065.
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Soil suppressiveness to soilborne pathogens can evolve following the incorporation of plant residues in the soil and solarization. We studied its occurrence by assessing disease incidence and severity in sandy soil which was infested after the disinfestation treatment. Disease incidence and severity of crown and root rot in cucumber plants inoculated with Fusarium oxysporum f. sp. radicis-cucumerinum macroconidia were reduced by 20 to 80% when seedlings were planted in the tested soils 2 to 34 months after soil amendment. Residues of Diplotaxis tenuifolia (wild rocket [WR]), Artemisia dracunculus (tarragon), Salvia officinalis (sage), and Brassica oleracea var. italica (broccoli) were most effective for inducing soil suppressiveness. Effective soil suppressiveness continued to be evident after repeated inoculations and plantings in the same soil without additional treatment between inoculations. Moreover, residues of WR induced soil suppressiveness in two additional tested soils differing in their physical and chemical properties. Residues of Rosmarinus officinalis (rosemary), Coriandrum sativum (coriander), Mentha piperita (peppermint), and B. oleraceae var. botrytis (cauliflower) induced disease suppression at the first inoculated planting but not upon repeated inoculation and planting. The contribution of soil solarization to the evolution of soil suppressiveness, albeit evident, was inconsistent. Soil suppressiveness to Fusarium crown and root rot was also observed when cucumber seed were sown in soils which were initially amended with WR residues and later infested with F. oxysporum f. sp. radicis-cucumerinum chlamydospores. There is a potential for the use of plant residues for inducing soil suppressiveness and further contributing to the control of diseases caused by soilborne pathogens.
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Hopkins, D. W., and E. G. Gregorich. "Decomposition of residues and loss of the δ-endotoxin from transgenic (Bt) corn (Zea mays L.) in soil." Canadian Journal of Soil Science 85, no. 1 (February 1, 2005): 19–26. http://dx.doi.org/10.4141/s03-073.
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Corn and other crops genetically modified to express the insecticidal δ-endotoxin from Bacillus thuringiensis (Bt) are grown widely across north America. Studies have shown that the δ -endotoxin can be stabilised on soil colloids where its activity is retained, but reports of direct ecological effects of the δ-endotoxin on soil processes are limited. We have determined the concentrations of the δ-endotoxin in organic residues fro m Bt-corn plants at increasing stages of ageing and decay, and the subsequent decomposition in soil of these residues and the δ-endotoxin in them. The δ-endotoxin concentrations declined from 6.8 μg g-1 in the fresh plant material, to 0.82 μg g-1 in the post-harvest residues collected in the fall, and to 0.026 μg g-1 in the residues collected from soil surface the following spring. The concentration of δ -endotoxin in buried residues collected in the spring was not significantly different from zero. When incubated in soil in the laboratory over 84 d, the δ-endotoxin decomposed more rapidly than bulk plant C by factors of 1.85 for the fresh plant materials and 3.21 for the post-harvest residues. Within 14 d of incubation, the δ-endotoxin concentration in the residues collected at the soil surface was below the limit of detection. We contrasted the laboratory decomposition data with data from a field experiment to estimate the period that the δ-endotoxin in corn residues may survive in the field. Based on estimates derived from this comparison, we predict that following an October harvest in eastern Ontario the δ-endotoxin would fall below the detection threshold during November for post-harvest residues. Since stabilisation of the δ-endotoxin on soil colloids depends on it surviving (i.e., not being decomposed) for long enough to be released from the plant residue matrix and come into proximity with colloid surfaces, the rapid decay of the δ-endotoxin suggests that only a small fraction of the δ-endotoxin from post-harvest residues persists long enough to become stabilised in the field. Key words: Bt, corn, crop residue decomposition, maize
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Dormaar, J. F., and J. M. Carefoot. "Implications of crop residue management and conservation tillage on soil organic matter." Canadian Journal of Plant Science 76, no. 4 (October 1, 1996): 627–34. http://dx.doi.org/10.4141/cjps96-112.
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Under natural grassland or native prairie, aboveground residue or surface litter modifies the microenvironment. It promotes water infiltration and, by insulating the soil surface, moderates soil temperatures and limits evaporation. Root mass decomposes and transforms within the conditions created by surface litter. Together with root exudates, this below-ground residue or subsurface litter reacts with soil minerals to form aggregates, lower bulk density and increase water-holding capacity. Bringing such soils under cultivation leads to lower soil organic matter content, thereby increasing bulk density. The role of surface litter becomes even more important, as it affects wind and water erosion, reduces the impact of raindrops, prevents crusting, protects the soil from drying by sublimation, and captures snow. Management of crop residues depends on the role of the residue. A distinction must be made between above- and below-ground residues: their roles are distinctly different. Aboveground crop residue protects the soil and creates the conditions for below-ground residue to decompose and transform. These decomposition products, in turn, create favourable soil structure for plant growth. Research is needed on the effect of repeated harvesting of "excess" aboveground residues. Key words: Labile organic matter, resilience, resistance, surface litter, subsurface litter
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Nelson, Darryl R., and Pauline M. Mele. "The impact of crop residue amendments and lime on microbial community structure and nitrogen-fixing bacteria in the wheat rhizosphere." Soil Research 44, no. 4 (2006): 319. http://dx.doi.org/10.1071/sr06022.
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Crop management practices can affect the soil microbial community, but it is not clear whether the effect of these practices is measurable at the wheat root–soil interface, where the plant exerts significant influence through root exudation. In this study, wheat plants were grown in soil amended with milled canola, lucerne, lupin, pea, and wheat residues with and without lime, to determine what changes occur to microbial community structure in the rhizosphere. Rhizosphere soil collected from wheat plants at the 5-leaf stage was assessed for overall microbial functional diversity using BIOLOG analysis and the diversity of the functional gene nifH using the polymerase chain reaction (PCR), terminal restriction fragment length polymorphism (T-RFLP), and cloning. Plant development was reduced in all residue amendments except lucerne, and a high positive correlation in the non-limited treatments between plant residue nitrogen (N) content and wheat shoot N suggested microbial competition for available N. Results from BIOLOG analysis indicated significant differences in rhizosphere microbial community structure due to lime, and to a lesser extent, residue type. Diversity, measured by the Shannon Diversity Index, was higher in limed rhizosphere soil, in addition to an increase in soils amended with lucerne, lupin, and pea residues compared with amendment with wheat, canola, and control soil. Each residue amendment promoted unique microbial communities determined by multi-dimensional scaling (MDS) and analysis of similarities (ANOSIM) of the BIOLOG data; the strongest effect was produced by addition of canola residues. N-fixing bacteria were also affected by lime, but residue effects were less apparent, especially between limed samples. The factor that correlated best with both BIOLOG and nifH T-RFLP data in non-limed soil was a combination of residue sodium (Na), copper (Cu), and manganese (Mn). In limed soil, phosphorus (P), calcium (Ca), and pH correlated well with BIOLOG data, and N, potassium (K), and iron (Fe) correlated with nifH T-RFLP data. A clone library of nifH sequences from control and limed, pea-amended soils revealed significant diversity amongst nifH sequences, most clustering with α-proteobacteria, and in some instances with Geobacter sulfurreducens. Clone distribution was significantly different for control soil and pea/lime soil, especially amongst the α-proteobacteria. The results suggest that rhizosphere microorganisms can be influenced by soil amendments, and change, depending on the type of residue applied. The addition of lime, however, produced the most significant changes in microbial community structure and nifH-containing rhizobacteria, highlighting the significant functional changes that occur when soil pH is increased.
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Burkhanova, Dilnavoza, Dilrabo Kodirova, Munisa Urmanova, Muradjan Karimov, and Matlyuba Usmonova. "Perceived methods for increasing the productivity of irrigated typical gray and grazing soils of Uzbekistan in non-traditional irrigation." E3S Web of Conferences 258 (2021): 03024. http://dx.doi.org/10.1051/e3sconf/202125803024.
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This article considers the effective effect of mulching of irrigated typical gray and meadow soils with plant residues and application of various fertilizers on soil fertility, mulching of typical gray soils with plant residues and application of various fertilizers (organic fertilizers, biohumus and biopreparations) in meadow soils. The effect on microbiological activity was determined. The application of various fertilizers (organic fertilizers, biohumus and biopreparations) to typical irrigated gray and meadow soils and mulching of the soil with plant residues have been shown to affect the growth and yield of winter wheat and cotton.
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Babu, C., P. Janaki, and C. Chinnusamy. "Effect of rate of application on degradation of imazethapyr in groundnut and soil under tropical Indian condition." Journal of Applied and Natural Science 7, no. 2 (December 1, 2015): 714–18. http://dx.doi.org/10.31018/jans.v7i2.671.
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Pesticides though formulated to be biologically degradable, few herbicides reported to cause surface and groundwater contamination which needs the monitoring of herbicide residues in environment continuously. Thus, to monitor the persistence and residues in crops, imazethapyr degradation studies were conducted in soil with groundnut cropping under Indian tropical condition. A groundnut field was treated with different doses of imazethapyr as early post emergence. Results showed that the degradation of imazethapyr in soil and groundnut plant followed first order reaction kinetics irrespective of the dose. The residue of imazethapyr persists in soil up to 60 days at higher rates of application while it persists up to 30 days in plant with the calculated half life of 2.8 to 7.4 days in soil and 5.1 to 5.9 days in plant. At the time of harvest, the residue of imazethapyr in soil, groundnut haulm or pods were below the detectable limit of 0.008 mg/kg across different doses of application. However, the continuous and inappropriate use in light textured soils may cause groundwater contamination and bioaccumulation in plant system. Hence, a pre harvest interval of 75 days must be allowed after the application of imazethapyr for the weed control in groundnut.
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Blair, Nelly, R. D. Faulkner, A. R. Till, and P. Sanchez. "Decomposition of 13C and 15N labelled plant residue materials in two different soil types and its impact on soil carbon, nitrogen, aggregate stability, and aggregate formation." Soil Research 43, no. 7 (2005): 873. http://dx.doi.org/10.1071/sr04137.
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Increasing soil organic matter (SOM) is a major factor in overcoming soil degradation. An incubation experiment using 2 soil types (Red Clay and Black Earth) and 2 different rotations, a clover (Trifolium subterraneum)/cereal rotation and a long fallow/cereal rotation, from a long-term crop rotation trial located at Tamworth, NSW, Australia was conducted to investigate the decomposition of 3 different plant materials, medic (Medicago truncatula) (C : N = 13), rice straw (Oryza sativa) (C : N = 25) and flemingia leaf (Flemingia macrophylla) (C : N = 13), labelled with 13C and 15N. A control treatment with no added residue was also included. The impact of the residue decomposition on total organic carbon, labile carbon, total nitrogen, aggregate stability and the formation of large macro-aggregates from smaller macro-aggregates were studied. Total C (CT), stable carbon isotope composition (δ13C), total N (NT), and %15N excess were measured by catalytic combustion and an isotope ratio mass spectrophotometer, while labile C (CL) was determined by oxidation with KMnO4. Aggregate stability [mean weight diameter (MWD)] was determined by immersion wet sieving. Correlations of C fractions with MWD were also investigated. The location of the newly added plant residue materials within soil aggregates was studied using a soil aggregate eroding machine. Loss of C from the added plant residues was highest for the medic and lowest for the flemingia, while the rice straw initially lost C at a slower rate but by 200 days was equal to the medic. The medic treatment was the only residue to lose N by gaseous loss during the experiment and it was all lost during the first 10 days. In both soils, the addition of residues increased CT and CL compared with the control treatment, with flemingia showing the greatest increase. Factors other than their C : N ratio were clearly determining C turnover. Addition of medic residues resulted in a rapid increase in MWD in both soils in the first 10 days compared with that at the commencement of the experiment. However, this was not maintained for the 200 days by which time MWD had decreased, but it was still greater than the starting point. By contrast, the addition of flemingia leaf exhibited a slower but more sustained increase to have the highest MWD at 200 days, equal to that of the medic treatment at 10 days. There was a positive correlation of CL with MWD at 200 days for both soils. Results from the soil aggregate eroding machine showed that a higher percentage of CT was derived from added plant residues in the outer one-third of the soil aggregates than in the inner two-thirds, with the greatest difference being for the flemingia treatment. There was no difference between different residue materials in the amount of CT derived from the added residues in the inner parts of soil aggregates. These results showed that soil macro-aggregates were forming around a central old aggregate by binding of smaller aggregates to it, with products formed as a result of the breakdown of plant residues binding them together. From the results obtained, and those of other researchers, a concept of macro-aggregate formation under different agricultural systems is proposed.
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TEJADA, M., M. HERNANDEZ, and C. GARCIA. "Soil restoration using composted plant residues: Effects on soil properties." Soil and Tillage Research 102, no. 1 (January 2009): 109–17. http://dx.doi.org/10.1016/j.still.2008.08.004.
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Burgess, M. S., G. R. Mehuys, and C. A. Madramootoo. "Decomposition of grain-corn residues (Zea mays L.): A litterbag study under three tillage systems." Canadian Journal of Soil Science 82, no. 2 (May 1, 2002): 127–38. http://dx.doi.org/10.4141/s01-013.
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This study was undertaken to obtain litterbag decomposition data for grain-corn residues in eastern Canadian conditions, to determine tillage and/or depth effects on residue mass loss, and to compare decomposition patterns for the different plant parts that constitute the residue (cobs, stems, leaves, husks). Mesh bags containing residues were buried or left on the soil surface in grain-corn plots under no-till, reduced tillage, and conventional tillage, and retrieved over a 2-yr period. Data were obtained separately for each plant part, then used to calculate pooled totals for all residues combined, for all residues except cobs, or for stems and leaves only, to facilitate comparison with studies based on different residue mixes. Buried residues lost mass faster than surface residues. Despite low overwinter temperatures, residue mass decreased substantially between placement in November and first sampling in mid- May. Surface litterbag residues lost 20% of initial mass during this period, residues buried at 5 cm lost 33%, and those at 20 cm lost 41%. Corresponding losses from mid-May to mid-October were 21, 42 and 32%, respectively. Mass loss was fastest for buried leaves, husks and stems (89-98% loss in 2 yr) and slowest for surface cobs (32% loss in 2 yr). Key words: Corn, maize, crop residue decomposition, litterbag, no-till, tillage
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Kerdraon, Lydie, Valérie Laval, and Frédéric Suffert. "Microbiomes and Pathogen Survival in Crop Residues, an Ecotone Between Plant and Soil." Phytobiomes Journal 3, no. 4 (January 2019): 246–55. http://dx.doi.org/10.1094/pbiomes-02-19-0010-rvw.
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The negative contribution of crop residues as a source of inoculum for plant diseases is well established. However, microbial ecologists have long reported positive effects of residues on the stability of agrosystems and conservation tillage practices have become increasingly widespread. Most studies have suggested that large microbial communities should be taken into account in plant disease management, but we know little about their ecological interaction with pathogens in the crop residue compartment. This review focuses on microbiomes associated with residues within the context of other microbial habitats in cereal-producing agroecosystems such as phyllosphere or rhizosphere. We connected residue microbiome with the survival of residue-borne fungal plant pathogens, thus combining knowledge in microbial ecology and epidemiology, two disciplines still not sufficiently connected. We provide an overview of the impact of residues on cereal disease epidemics and how dynamic interactions between microbial communities of nonburied residues during their degradation, along with soil and multitude of abiotic factors, can contribute to innovative disease management strategies, including next-generation microbiome-based biocontrol strategies. Starting from the classical but still relevant view of crop residues as a source of pathogen inoculum, we first consider possibilities for limiting the amount of residues on the soil surface to reduce the pathogen pressure. We then describe residues as a transient half-plant/half-soil compartment constituting a key fully fledged microbial ecosystem: in other words, an ecotone which deserves special attention. We focus on microbial communities, the changes in these communities over time and the factors influencing them. Finally, we discuss how the interactions between the microbial communities and the pathogens present on residues could be used: identification of keystone taxa and beneficial assemblages, then preservation of these taxa by adapted agronomic practices or development of synthetic communities, rather than the introduction of a single exogenous biocontrol species designed as a treatment product. [Formula: see text] Copyright © 2019 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .
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Chèneby, D., D. Bru, N. Pascault, P. A. Maron, L. Ranjard, and L. Philippot. "Role of Plant Residues in Determining Temporal Patterns of the Activity, Size, and Structure of Nitrate Reducer Communities in Soil." Applied and Environmental Microbiology 76, no. 21 (September 10, 2010): 7136–43. http://dx.doi.org/10.1128/aem.01497-10.
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ABSTRACT The incorporation of plant residues into soil not only represents an opportunity to limit soil organic matter depletion resulting from cultivation but also provides a valuable source of nutrients such as nitrogen. However, the consequences of plant residue addition on soil microbial communities involved in biochemical cycles other than the carbon cycle are poorly understood. In this study, we investigated the responses of one N-cycling microbial community, the nitrate reducers, to wheat, rape, and alfalfa residues for 11 months after incorporation into soil in a field experiment. A 20- to 27-fold increase in potential nitrate reduction activity was observed for residue-amended plots compared to the nonamended plots during the first week. This stimulating effect of residues on the activity of the nitrate-reducing community rapidly decreased but remained significant over 11 months. During this period, our results suggest that the potential nitrate reduction activity was regulated by both carbon availability and temperature. The presence of residues also had a significant effect on the abundance of nitrate reducers estimated by quantitative PCR of the narG and napA genes, encoding the membrane-bound and periplasmic nitrate reductases, respectively. In contrast, the incorporation of the plant residues into soil had little impact on the structure of the narG and napA nitrate-reducing community determined by PCR-restriction fragment length polymorphism (RFLP) fingerprinting. Overall, our results revealed that the addition of plant residues can lead to important long-term changes in the activity and size of a microbial community involved in N cycling but with limited effects of the type of plant residue itself.
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Stumborg, Mark, Lawrence Townley-Smith, and Ewen Coxworth. "Sustainability and economic issues for cereal crop residue export." Canadian Journal of Plant Science 76, no. 4 (October 1, 1996): 669–73. http://dx.doi.org/10.4141/cjps96-117.
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Soil conservation and sustainability concerns, and a lack of markets for crop residues, have left producers with few alternatives for cereal residue export beyond cattle feed or livestock bedding. With the increasing producer use of minimum and zero-tillage systems, the management of crop residues has become an important issue. Opportunities for residue removal may exist provided markets are developed for the material and long-term soil sustainability concerns are addressed.Recent research on the effect of residue removal in Saskatchewan has shown that there is little or no impact on soil organic matter provided adequate fertilization is practised and tillage is reduced. Assuming that 750 kg ha−1 of retained residue is adequate for erosion protection in reduced tillage systems, significant quantities of residues may be available for export from the Black Soil zone. The economic returns to producers are such that residue export is an attractive diversification option. Key words: Crop residues, economics, residue export, soil erosion, soil nutrients, soil carbon
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Gupta, Raj, DK Benbi, and IP Abrol. "Ecological Significance of Residues Retention for Sustainability of Agriculture in the Semi-arid Tropics." Journal of Agronomy Research 3, no. 4 (June 7, 2021): 9–30. http://dx.doi.org/10.14302/issn.2639-3166.jar-21-3822.
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In South Asia, land degradation is primarily a monsoon mediated phenomenon restricted to 2-3 rainy months. The overall strategy for land degradation neutrality should (i) favour actions that keep soils covered with residues and (ii) plant kharif (rainy season) crop before the onset of monsoons to provide soil cover. Retention of anchored residues provides surface cover, increases microbial activity, carbon sequestration, and availability of nutrients. Surface retained residues reduce root zone salinization, detoxify phytotoxic monomeric Al in acidic soils and enhance the potential for use of brackish ground water in crop production. Residues covers save irrigation water and overcome the ill effects of poor agronomic and water management practices. Early direct dry seeding in surface retained residues has the potential of making kharif season planting independent of the onset of monsoon rains in South Asia and helps reduce acreages of Kharif and Rabi fallow lands. For improving carbon content in Indian soils, perhaps the most important priority is to devise tillage and crop residue management approaches that promote in situ rain water storage and its use for growing more crops. The paper summarises how crop residues fuel and drive soil functions and related ecosystem services and plant growth.
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Rui, Junpeng, Jingjing Peng, and Yahai Lu. "Succession of Bacterial Populations during Plant Residue Decomposition in Rice Field Soil." Applied and Environmental Microbiology 75, no. 14 (May 22, 2009): 4879–86. http://dx.doi.org/10.1128/aem.00702-09.
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ABSTRACT The incorporation of rice residues into paddy fields strongly enhances methane production and emissions. Although the decomposition processes of plant residues in rice field soil has been documented, the structure and dynamics of the microbial communities involved are poorly understood. The purpose of the present study was to determine the dynamics of short-chain fatty acids and the structure of bacterial communities during residue decomposition in a rice field soil. The soil was anaerobically incubated with the incorporation of rice root or straw residues for 90 days at three temperatures (15, 30, and 45°C). The dynamics of fatty acid intermediates showed an initial cumulative phase followed by a rapid consumption phase and a low-concentration quasi-steady state. Correspondingly, the bacterial populations displayed distinct successions during residue decomposition. Temperature showed a strong effect on the dynamics of bacterial populations. Members of Clostridium (clusters I and III) were most dominant in the incubations, particularly in the early successions. Bacteroidetes and Chlorobi were abundant in the later successions at 15 and 30°C, while Acidobacteria were selected at 45°C. We suggest that the early successional groups are responsible for the decomposition of the easily degradable fraction of residues, while the late successional groups become more important in decomposing the less-degradable or resistant fraction of plant residues. The bacterial succession probably is related to resource availability during residue decomposition. The fast-growing organisms are favored at the beginning, while the slow-growing bacteria are better adapted in the later stages, when substrate availability is limiting.
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Riddle, Rachel N., John O'Sullivan, Clarence J. Swanton, and Rene C. Van Acker. "Crop Response to Carryover of Mesotrione Residues in the Field." Weed Technology 27, no. 1 (March 2013): 92–100. http://dx.doi.org/10.1614/wt-d-12-00071.1.
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Two field residue studies were conducted from 2005 to 2007 in Simcoe, Ontario, Canada, to evaluate the effects of mesotrione soil residues on injury, plant dry weight, and yield of sugar beet, cucumber, pea, green bean, and soybean and to verify the potential of reducing a 2-yr field-residue study (conventional residue carryover) to a 1-yr field study (simulated residue-carryover study) by growing these crops in soil treated with reduced rates of mesotrione applied in the same year. There was a significant difference in mesotrione carryover between 2006 and 2007 and differences between years can be explained by differences in soil pH and soil moisture. The conventional and the simulated residue-carryover studies successfully measured mesotrione persistence and rotational crop sensitivity. Both studies showed that sugar beet was the most-sensitive crop with injury, plant dry weight reduction, and yield loss because of mesotrione residues as high as 100%. Green bean was the next most-sensitive crop to mesotrione residues followed by pea, cucumber, and soybean. The simulated residue-carryover study provided a more-rigorous test of rotational crop sensitivity to mesotrione residues than the conventional residue-carryover study, especially at higher rates for the more-sensitive crops. For the other crops, responses to mesotrione residues were similar between the conventional and simulated residue-carryover studies.
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Henderson, Sherri L., Catherine E. Dandie, Cheryl L. Patten, Bernie J. Zebarth, David L. Burton, Jack T. Trevors, and Claudia Goyer. "Changes in Denitrifier Abundance, Denitrification Gene mRNA Levels, Nitrous Oxide Emissions, and Denitrification in Anoxic Soil Microcosms Amended with Glucose and Plant Residues." Applied and Environmental Microbiology 76, no. 7 (February 12, 2010): 2155–64. http://dx.doi.org/10.1128/aem.02993-09.
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ABSTRACT In agricultural cropping systems, crop residues are sources of organic carbon (C), an important factor influencing denitrification. The effects of red clover, soybean, and barley plant residues and of glucose on denitrifier abundance, denitrification gene mRNA levels, nitrous oxide (N2O) emissions, and denitrification rates were quantified in anoxic soil microcosms for 72 h. nosZ gene abundances and mRNA levels significantly increased in response to all organic carbon treatments over time. In contrast, the abundance and mRNA levels of Pseudomonas mandelii and closely related species (nirS P) increased only in glucose-amended soil: the nirS P guild abundance increased 5-fold over the 72-h incubation period (P < 0.001), while the mRNA level significantly increased more than 15-fold at 12 h (P < 0.001) and then subsequently decreased. The nosZ gene abundance was greater in plant residue-amended soil than in glucose-amended soil. Although plant residue carbon-to-nitrogen (C:N) ratios varied from 15:1 to 30:1, nosZ gene and mRNA levels were not significantly different among plant residue treatments, with an average of 3.5 � 107 gene copies and 6.9 � 107 transcripts g−1 dry soil. Cumulative N2O emissions and denitrification rates increased over 72 h in both glucose- and plant-tissue-C-treated soil. The nirS P and nosZ communities responded differently to glucose and plant residue amendments. However, the targeted denitrifier communities responded similarly to the different plant residues under the conditions tested despite changes in the quality of organic C and different C:N ratios.
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Shetty, K. G., K. V. Subbarao, O. C. Huisman, and J. C. Hubbard. "Mechanism of Broccoli-Mediated Verticillium Wilt Reduction in Cauliflower." Phytopathology® 90, no. 3 (March 2000): 305–10. http://dx.doi.org/10.1094/phyto.2000.90.3.305.
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Broccoli is resistant to Verticillium dahliae infection and does not express wilt symptoms. Incorporation of broccoli residues reduces soil populations of V. dahliae. The effects of broccoli residue were tested on the colonization of roots by V. dahliae, plant growth response, and disease incidence of both broccoli and cauliflower in soils with different levels of V. dahliae inoculum and with or without fresh broccoli residue amendments. The three soils included a low-Verticillium soil, a high-Verticillium soil, and a broccoli-rotation soil (soil from a field after two broccoli crops) with an average of 13, 38, and below-detectable levels of microsclerotia per g of soil, respectively. Cauliflower plants in broccoli-amended high-Verticillium soil had significantly (P ≤ 0.05) lower wilt incidence and severity than did plants in unamended soil. An immunohistochemical staining assay utilizing a monoclonal antibody specific to V. dahliae was used to determine colonization of the root cortex. Despite the absence of wilt symptoms, broccoli roots were colonized by V. dahliae. In high-Verticillium soil, the broccoli residue amendment caused a marked reduction in colonization rate of V. dahliae per unit of inoculum on both cauliflower and broccoli roots. In addition to its detrimental effects on the viability of microsclerotia in soil, broccoli residue may also have an inhibitory effect on the root-colonizing potential of surviving microsclerotia.
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Do, T. C. V., and H. W. Scherer. " Compost and biogas residues as basic materials for potting substrates." Plant, Soil and Environment 58, No. 10 (October 12, 2012): 459–64. http://dx.doi.org/10.17221/445/2012-pse.
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Recent concerns over the environmental impact of peat harvesting have led to restrictions on the production of peat based potting substrates. Therefore the objective of our study was to evaluate the use of compost and biogas residues without and each with 20% additives (Perlite, Styromull, Hygromull, Lecaton, Peat, Cocofiber) as a substitute for peat. Ryegrass (Lolium perenne L.), chosen as an experimental plant, was cut four times. The results reveal that compost and biogas residues are suitable potting substrates. The incorporation of additives mixed into the basic materials partly resulted in higher yield and nutrient uptake. However, the difference among additives was mainly insignificant. Incorporation of Hygromull, especially into biogas residues favored plant growth and increased the uptake of nutrients, which is attributed to the fact that Hygromull stores nutrients and delivers them even later in the growing season. Furthermore Hygromull reduces the salt concentration of the medium, resulting in favored plant growth of younger plants.
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Rusakova, I. V. "BIOPREPARATIONS FOR DECOMPOSITION OF PLANT RESIDUES IN AGROECOSYSTEMS." Juvenis scientia, no. 9 (September 30, 2018): 4–9. http://dx.doi.org/10.32415/jscientia.2018.09.01.
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The article reviews the main results of scientific research in the country and abroad on the evaluation of microbiological preparations-destructors of post-harvest plant residues in agroecjsistems. It is shown that plant remains are the most important resource for reproduction of arable soils fertility. The most environmentally feasible and cost-effective way to recycle them is to enclose in the soil as a fertilizer, providing a return to the agrobiological circulation of nutrients and organic matter. One way to accelerate the decomposition and increase of the humification coefficient of post-harvest residues, which has become widespread in recent years in the practice of the agro-industrial complex, can be inoculation with microbiological destructive preparations before being embedded in the soil. The data of many authors confirm that the use of biopreparations promotes the acceleration of decomposition of high-carbon plant residues and a decrease in their negative effect, an increase in soil biogenicity, and an increase in the yield of subsequent crops. The most active biopreparations "work" in the initial terms of decomposition, in conditions of humidity and temperature optimal for the microbiota. The effectiveness of biopreparations increases in combination with compensating doses of nitrogen. Along with positive results, in scientific publications there are data on the lack of influence of biological products on the rate of straw decomposition. It is concluded that biologics-destructors can be used in agricultural practice to treat stubble and straw before it is application in the soil in order to accelerate the decomposition, increase the yield of subsequent crops. For a better understanding of mechanisms action of biologics, preparation of recommendations for their practical use, further experimental studies are needed in field and laboratory conditions.
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Marles, Susan M., Thomas D. Warkentin, and Frederick A. Holm. "Field Pea Seed Residue: a Potential Alternative Weed Control Agent." Weed Science 58, no. 4 (December 2010): 433–41. http://dx.doi.org/10.1614/ws-d-10-00015.1.
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Field pea seed from bin cleaning operations stored overwinter on nearby cropland was observed to correlate with weed and crop growth suppression for up to three subsequent years. To explore the phenomenon more explicitly, plant growth suppression trials were undertaken with soil sampled 18 mo apart from two locations that had contained field pea seed residues. Test plant species grown in the residue-affected and nearby residue-free soils were compared in greenhouse experiments. Germination was either fully inhibited or emergence was delayed by more than one week. Dry matter accumulation of test species grown in residue-affected soil was significantly reduced compared to dry matter of these test species grown in residue-free soil (P < 0.0001). Canola and field pea were inhibited more than wheat and green foxtail over both years. Greenhouse trials also revealed that germination of wild oat was inhibited in the residue-affected soils, although wheat and grassy weeds were less suppressed than dicots overall. Significant reductions of weed species diversity and abundance were correlated to residue-affected soils (P < 0.0001) when compared to residue-free soils using multi-response permutations procedures. Germination of wheat and canola seed was inhibited, using aqueous extracts of weathered pea seeds or extracts of the residue-affected soil in bioassays in sterile media. An allelopathic response was proposed to explain the above results, indicating a need for further research on this system. Weed management strategies could be developed with field pea seed residues to provide innovative weed control techniques.
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Lim, Da-Jung, Seon-Wook Kim, Young-Eun Kim, Ji-Hyun Yoon, Hyun-Jeong Cho, Byeung-Gon Shin, Hyo-Young Kim, and In-Seon Kim. "Plant-Back Intervals of Imicyafos Based on Its Soil Dissipation and Plant Uptake for Rotational Cultivation of Lettuce and Spinach in Greenhouse." Agriculture 11, no. 6 (May 26, 2021): 495. http://dx.doi.org/10.3390/agriculture11060495.
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The plant-back intervals (PBIs) of imicyafos were investigated for rotational cultivation of lettuce and spinach in greenhouses. Imicyafos dissipation in soil and its plant uptake were evaluated by liquid chromatography-tandem mass spectrometry. Bioconcentration ratios (BCRs) were calculated by comparing the residues in plants to the initial residue in soil. The BCRs were used to calculate the soil acceptable residues (SARs) transferable to plants at the Positive List System (PLS) level. The number of days, PBIs for reaching SARs were obtained from the dissipation equation for imicyafos in soil. In soil, imicyafos followed first order dissipation kinetics (R2 = 0.975) with a half-life of 40.8 days. The BCRs ranged from 0.041 to 0.469 in the edible leaf parts of lettuce and 0.006 to 0.134 in those of spinach. The SARs ranged from 0.021 to 0.244 for lettuce and 0.075 to 1.667 mg kg−1 for spinach. The PBIs of imicyafos were estimated to be 213.9 to 357.3 days for lettuce and 100.8 to 283.6 days for spinach. This study suggests at least a minimum 1-year interval after the final application of imicyafos as a management method that complies with the PLS for the rotational cultivation of lettuce and spinach.
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Savich, Vitaly Igorevich, Hafiza Tuymurodovna Artikova, Shavkatullo Shukurovich Nafetdinov, and Khilola Hamroevna Salimova. "Optimization Of Plant Development In Case Of Soil Salinization." American Journal of Agriculture and Biomedical Engineering 03, no. 02 (February 28, 2021): 24–29. http://dx.doi.org/10.37547/tajabe/volume03issue02-05.
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This article discusses the improvement of the development of biotests in saline soils with the addition of zeolite, phosphogypsum, organic fertilizers. The development of biotests on seawater with a concentration of 1-10 g / l improved when humates, KNO3, and water extracts from crop residues were added to the water. A decrease in the salinity of the upper soil layer is shown when an interlayer with large pores from high moor peat is created at a depth of 25 cm.
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Alinejadian-Bidabadi, Afsaneh, Abbas Maleki, and Mahtab Roshaniyan. "The impact of tillage systems and crop residues on microbial mass and soil structure stability indices." Spanish Journal of Agricultural Research 19, no. 1 (February 4, 2021): e1101. http://dx.doi.org/10.5424/sjar/2021191-15794.
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Aim of study: This research investigated the effects of management practices, including plant residues and tillage practices, on soil stability indices, microbial biomass carbon, and the number of bacteria.Area of study: Northern Khorasan Province, Iran.Material and methods: This study explored the effects of the three year-old tillage systems of conventional tillage (CT), minimum tillage (MT), and no-tillage (NT) at three levels 0, 40, and 70% of plant residues on soil physical and microbiological properties for a rotation of three years (wheat, canola, and wheat). Variables measured in this study included the whole soil stability index, the normalized stability index, the percentage of aggregate destruction (PAD), the number of bacteria, and microbial biomass carbon.Main results: Management practices could affect variables, such as soil structure stability as well as the number of bacteria. The results also showed that soils of higher stability were more resistant to soil degradation. In addition, by reducing tillage and adding plant residues, the PAD index decreased significantly. NT and MT practices improved soil structure stability indices and significantly increased the number of bacteria as well as microbial biomass carbon in contrast to CT, what could be attributed to the increased soil organic matter.Research highlights: Reduced tillage practices showed the potential for enhancing soil physical quality only through improving aggregate stability. Therefore, NT with 70% residue retention was found to be suitable to improve soil sustainability indices and increased soil microbial population.
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Hill, B. D., J. R. Moyer, D. J. Inaba, and R. Doram. "Effect of moisture on quinclorac dissipation in Lethbridge soil." Canadian Journal of Plant Science 78, no. 4 (October 1, 1998): 697–702. http://dx.doi.org/10.4141/p97-119.
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This study examined the dissipation and carry-over of quinclorac residues in a Lethbridge sandy clay loam with 2% organic matter. Experiments were conducted in covered outdoor lysimeters using different simulated rainfall regimes. Quinclorac residues were monitored in the top 10 cm of soil using chemical residue analysis and the activity of carried-over residues assessed by bioassay. Quinclorac dissipation was very slow although, in general, the amount of residue remaining decreased with increased moisture (117–447 mm) applied. Forty-eight weeks after quinclorac application, 85, 66, 52, 49, and 48% of initial residues remained in the very dry, dry, normal, wet and very wet moisture regimes, respectively. Residue persistence could be accurately predicted (r2 = 0.96) using a simple moisture model (% quinclorac remaining = 101% −0.18 × mm cumulative moisture) for up to 300 mm moisture. Quinclorac dissipation was attributed mostly to the residues leaching beyond the 0- to 10-cm soil layer. A separate laboratory experiment showed that 80% of applied quinclorac leached through 9.7-cm deep soil columns when 304 mm of water was applied. The quinclorac residues remaining after 48 wk were biologically available and caused injury to fababeans (Vicia faba L.) under all moisture regimes. Key words: Quinclorac, persistence, moisture effects, leaching, residue carry-over, recropping
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Armstrong, R. D., K. McCosker, G. Millar, and M. E. Probert. "Fluxes of nitrogen derived from plant residues and fertiliser on a cracking clay in a semi-arid environment." Australian Journal of Agricultural Research 49, no. 3 (1998): 437. http://dx.doi.org/10.1071/a97069.
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The feasibility of using legume leys to redress declining levels of soil nitrogen (N) fertility on the heavy clay Vertisols of the northern Australian grain belt depends partly on the ability of plant residues to supply N directly to subsequent cereal crops. An alternative is the use of fertiliser N in continuous cereal cropping. Two experiments were conducted (one in the field, the other under polyhouse conditions) to compare the uptake of N from either plant residues or ammonium sulfate fertiliser that had been labelled with 15N. In a field trial, 15N-labelled shoots of grain sorghum and Desmanthus virgatus and ammonium sulfate were applied to micro-plots and the flux of the added N between different soil pools and a wheat crop was followed over 219 days. Only small amounts of residue-derived N (<5%) were recovered in the mineral N of the soil at a depth of 0-10 cm, whereas over 88% of the fertiliser N was present as mineral N soon after adding the fertiliser. Soil microbial biomass-N was increased following addition of residues. Recovery of added 15N in the wheat crop was much higher from the fertiliser (35%) than from the 2 residue sources (<5%). The pot trial compared a wider range of 15N-labelled residues (shoot and root residues of Desmanthus virgatus, Lablab purpureus, and sorghum) with several rates of ammonium sulfate, applied in the presence and absence of non-labelled grain sorghum residues, over 4 cropping cycles. Dry matter production and N uptake were increased by application of fertiliser N, although the response was reduced in the presence of non-labelled sorghum residues; responses to residue N were much smaller than those to fertiliser N. In the first crop following residue application <7% of residue N was recovered, increasing to 12-23% over the 4 crops. Recovery of fertiliser N by the crops increased with the rate of application, and also depended on whether it was applied together with residues. A feature of the results, in both the field and pot experiments, was the large proportion of applied 15N that could not be accounted for in either the soil or the crops, and these losses have been attributed to denitrification.
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Schoenau, Jeff J., and Constantine A. Campbell. "Impact of crop residues on nutrient availability in conservation tillage systems." Canadian Journal of Plant Science 76, no. 4 (October 1, 1996): 621–26. http://dx.doi.org/10.4141/cjps96-111.
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Crop residue management is a key consideration when attempting to optimize fertility in conservation tillage systems. Major factors affecting the impact of crop residues on nutrient availability include the chemical composition of the residue [e.g. carbon (C) to nitrogen (N) ratio], residue placement, fertilizer placement in relation to residue and time. Greater surface accumulation of crop residues in reduced and no-till systems tends to slow decomposition of N-poor residues such as cereal straw, and crop N supply during the current year can be reduced by immobilization if the straw is incorporated close to the time of high crop demand. Similarly, placement of fertilizer directly in the surface straw residue can reduce fertilizer use efficiency due to greater immobilization. Greater immobilization in reduced and no-till systems can enhance the conservation of soil and fertilizer N in the long term, with higher initial N fertilizer requirements decreasing over time because of 1) reduced losses by erosion and 2) the build-up of a larger pool of readily mineralizable organic N. For N-rich residues, such as legumes, volatilization losses may be greater when these residues are left on the surface than when incorporated into soil. Leaching of soluble phosphorus and sulfur compounds from standing and surface-placed crop residues into the mineral soil below may be a significant pathway for recycling of these elements in no-till systems. Greater coverage of the soil surface by crop residues can increase soil moisture and affect soil biological activity related to nutrient turnover. Future research should address how above- and below-ground decomposition processes differ for a wider range of crop residues and nutrients, emphasizing both short and long-term nutrient recycling. Key words: Crop residue, no-till, nutrient availability, nutrient cycling
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Broersma, K., N. G. Juma, and J. A. Robertson. "Plant residue and cropping system effects on N dynamics in a Gray Luvisolic soil." Canadian Journal of Soil Science 80, no. 2 (May 1, 2000): 277–82. http://dx.doi.org/10.4141/s99-070.
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Soil samples from differing cropping systems were amended with 15N-labeled plant residues having varying carbon to nitrogen (C:N) ratios to quantify N dynamics in a Gray Luvisolic soil. For non-amended cropping systems a significantly greater amount of total N was mineralized from the continuous legume (CL) than from the continuous grass (CG), barley/forage (BF) rotations, or continuous barley (CB) cropping systems. The addition of the fababean (Vicia faba L.) plant residue resulted in net N mineralization from most of the cropping systems. After 20 wk, 14.0%, 10.5% and 7.1% of the 15N was mineralized from fababean, barley (Hordeum vulgare L.) and fescue (Festuca rubra L.) amended residues, respectively, when averaged across cropping systems. Key words: Crop residues, cropping systems, Gray Luvisol, N mineralization, 15N, soil amendments
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Butnan, Somchai, and Patma Vityakon. "The interactive effects of soil disturbance and residue quality on soil nitrogen mineralisation in a tropical sandy soil." Soil Research 58, no. 3 (2020): 277. http://dx.doi.org/10.1071/sr18350.
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Soil conservation practices, such as reduced and no tillage, have been found to enhance soil nitrogen (N) sequestration through decreasing the rate of N mineralisation of added organic materials. Nitrogen mineralisation is not only affected by tillage, but also by the quality (chemical composition) of the organic residues. This study evaluated the interaction of residue quality and soil disturbance on N mineralisation in a sandy soil. A 112-day incubation experiment was conducted with two levels of soil disturbance (undisturbed and disturbed conditions) and five plant residue amendments of contrasting quality. The contrasting quality (N, lignin (L), and polyphenols (Pp)) (in g kg–1) amendments follow: (i) unamended; (ii) Sesbania grandiflora (N 44, L 173, Pp 9.2); (iii) Indigofera hirsuta (N 41, L 177, Pp 30); (iv) Dipterocarpus tuberculatus (N 8.2, L 203, Pp 71); and (v) Eucalyptus camaldulensis (N 9.7, L 126, Pp 110). Residues (ii) and (iii) were fresh legume leaves, while (iv) and (v) were non-legume leaf litter. Disturbance only significantly increased N mineralisation rates in the legume-residue treated soils (increases of 18.8% for S. grandiflora and 27.1% for I. hirsuta) during the early stage of decomposition (first 14 days). In the legume treatment, disturbance significantly increased the ammonification, but decreased nitrification in soil relative to undisturbed soils. The difference in patterns of ammonification and nitrification was more pronounced in the early than in the later period of decomposition. This indicated an inhibitory effect of soil disturbance on nitrification, which was particularly pronounced in the legume-treated soils. The Pp content of residues was the major quality parameter regulating the soil ammonium-N and nitrate-N concentrations. Minimum soil disturbance should be adopted under legume soil organic amendment so that both ammonification and nitrification components of N mineralisation process can occur normally, and nitrate-loving crops can take up N in the form of nitrate-N which will enhance their yields. Moreover, undisturbed conditions under legume organic amendments reduced N mineralisation, resulting in enhancing soil N sequestration.
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Yee, Dennis, Pearl Weinberger, and Shahamat U. Khan. "Release of Soil-Bound Prometryne Residues Under Different Soil pH and Nitrogen Fertilizer Regimes." Weed Science 33, no. 6 (November 1985): 882–87. http://dx.doi.org/10.1017/s0043174500083545.
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The release of soil-bound14C-prometryne [N,N′-bis(l-methylethyl)-6-(methylthio)-1,3,5-triazine-2,4-diamine] residues was affected by soil pH, fertilizer treatments (with or without plants), and the crop species wheat [Triticum aestivum(L.) Merr. ‘Marquis’] and soybean [Glycine max(L.) Merr. ‘Maple Presto’]. More of the bound radioactivity was released following large pH changes in the soil than with small deviations. In addition, more14C-prometryne was found in the extracts of the soil incubated with large pH alterations. Fertilizing with ionic nitrogen sources (NO3–and NH4+) in the absence of plants was also responsible for releasing higher levels of radioactivity than with the nonionic fertilizer urea. These fertilizer-induced differences in release were not apparent when wheat plants were added to the system. Release of the bound radioactivity, however, was plant specific, particularly in the rhizoplane, since soybean roots elicited a greater release in the rhizoplane than wheat roots. Transport and metabolism of these residues were also plant specific.
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Ambrosano, Edmilson José, Paulo Cesar Ocheuze Trivelin, Heitor Cantarella, Gláucia Maria Bovi Ambrosano, and Takashi Muraoka. "Nitrogen mineralization in soils amended with sunnhemp, velvet bean and common bean residues." Scientia Agricola 60, no. 1 (February 2003): 133–37. http://dx.doi.org/10.1590/s0103-90162003000100020.
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Nitrogen (15N) released from sunnhemp (Crotalaria juncea), velvet bean (Mucuna aterrima) and from Phaseolus bean residues was evaluated after incubation of the plant material in an Eutrudox and a Paleudalf, in a greenhouse experiment with pots containing 6 kg of air dried soil. Dry matter equivalent to 13 Mg ha-1 of Phaseolus bean residues and the same amount of above ground parts of the leguminous species, associated to 2.7 and 2.2 Mg ha-1 of roots of sunnhemp and velvet bean respectively, were incorporated into the soil. A completely randomized experimental design was adopted, with treatments arranged in a 2 <FONT FACE=Symbol>´</FONT> 3 + 1 factorial, replicated three times. The treatments were the following: two soils (Eutrudox and Paleudalf) and three plant materials: two green-manures (sunnhemp or velvet bean), and Phaseolus bean residues, besides one control without plant incorporation into the soil. For the green-manure treatments there were two sub-treatments for each legume species, with 15N labeling of either shoots or roots. Soil moisture was maintained relatively constant during the experiment al period and the treatments were sampled weekly during 49 days. Total mineral nitrogen in the soil, as well as that derived from the legume plants were determined by isotope dilution. Nitrogen from the velvet bean accounted for a greater proportion of the soil inorganic N; shoots were responsible for most of N accumulated. Dry bean residues caused immobilization of inorganic N. The leguminous species added were intensively and promptly mineralized preserving the soil native nitrogen. Mineralization of the legume plant N was greater in the Paleudalf soil than in the Eutrudox.
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Xu, Yingde, Fan Ding, Xiaodan Gao, Yang Wang, Ming Li, and Jingkuan Wang. "Mineralization of plant residues and native soil carbon as affected by soil fertility and residue type." Journal of Soils and Sediments 19, no. 3 (October 15, 2018): 1407–15. http://dx.doi.org/10.1007/s11368-018-2152-7.
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Franco, Miguel Henrique Rosa, Vinícius Teixeira Lemos, André Cabral França, Nykolas Carvalho Schiavon, Marco Túlio Gomes Albuquerque, Ademílson de Oliveira Alecrim, and Leonardo D'Antonino. "Physiological and morphological characteristics of Phaseolus vulgaris L. grown in soil with picloram residues." Pesquisa Agropecuária Tropical 46, no. 3 (September 2016): 276–83. http://dx.doi.org/10.1590/1983-40632016v4640169.
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ABSTRACT The long lasting residual effect of some auxin herbicides depends on soil characteristics and may cause phytotoxicity on subsequent crops. Picloram is one of the main herbicides used in pastures, presenting a long lasting residual effect in the soil. This study aimed at determining the physiological and morphological characteristics of common bean plants grown in soil contaminated with picloram, under greenhouse conditions. A complete randomized blocks design, with treatments consisting of picloram doses (0 g ha-1, 7.5 g ha-1, 15 g ha-1, 30 g ha-1, 60 g ha-1 and 120 g ha-1 a.i.), with five replications, was used. Urochloa brizantha was sown in pots, and its height and shoot fresh and dry matter were evaluated. In the same pots, Phaseolus vulgaris was sown as a bio-indicator of picloram, and the following characteristics were measured: plant height, fresh and dry matter, phytotoxicity, leaf area, number of leaves per plant, maximum photosynthetic efficiency and relative electron transport rate. The phytoremediation process occurs in soil with picloram residues (up to 30 g ha-1) when covered by U. brizantha for 150 days. The common bean plants show a good potential as biological indicator of the presence of picloram residues in the soil.
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Ebrahimi, Nashmin, Helinä Hartikainen, Asko Simojoki, Roghieh Hajiboland, and Mervi M. Seppänen. "Dynamics of dry matter and selenium accumulation in oilseed rape (Brassica napus L.) in response to organic and inorganic selenium treatments." Agricultural and Food Science 24, no. 2 (June 27, 2015): 104–17. http://dx.doi.org/10.23986/afsci.48346.
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The uptake by and subsequent translocation of selenium (Se) within the plant is dependent on its chemical from and soil properties that dictate this trace element’s bioavailability. Plant species differ in their tendency to accumulate Se. Se taken-up by plants is returned to soil in plant residues, but the bioavailability of organic Se in those residues is poorly known. We investigated the impact of inorganic (Na2SeO4), organic (Se-enriched stem and leaf residues) Se applications and also soil microbial respiration on the growth and Se concentrations of various plant organs of oilseed rape (Brassica napus L.) during its development from the rosette to the seed filling stage. Both inorganic and organic Se slightly improved plant growth and enhanced plant development. Inorganic Se was more bioavailable than the organic forms and resulted in 3-fold to 6-fold higher Se concentrations in the siliques. Inorganic Se in autoclaved soil tended to elevate the Se concentration in all plant parts and at all growth stages. The organic Se raised Se concentrations in plants much less effectively than the inorganic selenate. Therefore, the use of inorganic Se is still recommended for biofortification.
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Arani, Abolfazl Baghbani, Amin Namdari, and Hossein Nazarli. "Wheat Grain Enrichment with Zinc Through Using Zinc Fertiliser and Preceding Plant Residues Incorporation." Agriculture (Pol'nohospodárstvo) 64, no. 2 (June 1, 2018): 80–86. http://dx.doi.org/10.2478/agri-2018-0008.
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Abstract Micronutrients and particularly zinc (Zn) deficiency affects crops productivity and human health, therefore improving Zn concentration within plant tissues might be regarded as an aim of sustainable agriculture. In this respect, a field experiment was carried out to examine the potential influence of preceding crop residues including bean and wheat incorporation into the soil as a way to improve zinc accumulation within subsequent wheat (Triticum aestivum L.) grain. The experiment was initiated at autumn 2014 and in the first year, a piece of farm land in Dehaghan-Isfahan-Iran was divided into two equal parts devoted to wheat and bean cultivation. At the end of the harvest season, aboveground plant residues were incorporated to 0-30 cm layer of soil. In the next year, the entire farm devoted to wheat production. The applied treatments included: control, zinc sulfate (60 kg/ha), wheat residues, bean (Phaseolus vulgaris L.) residues, wheat residues + zinc sulfate and bean residue + zinc sulfate. The results of analysis of variance showed the highly significant differences between treatments in terms of grain zinc, protein, phytic acid to zinc molar ratio (PA/Zn), quantitative yield and soil electrical conductivity (EC). Soil pH and organic carbon (OC) were not affected by treatments while soil EC significantly increased by using plant residues. The highest grain yield (3.8 t/ha), grain protein (10.3 mg/kg) and zinc concentrations (36 mg/kg) were obtained by using bean residues plus ZnSO4 while the lowest quantities were related to control treatment. The treatments had no significant impact on grain acid phytic concentration but phytic acid / zinc molar ratio was affected by treatments and the lowest ratio (which is a positive attribute) was measured from plots containing bean residues plus ZnSO4 while the highest occurred in control plots.
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Beckie, Hugh J., and Robert B. McKercher. "Soil Residual Properties of DPX-A7881 Under Laboratory Conditions." Weed Science 37, no. 3 (May 1989): 412–18. http://dx.doi.org/10.1017/s0043174500072143.
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Growth chamber studies were conducted to examine the soil residual properties of DPX-A7881, a new sulfonylurea herbicide. The phytotoxic residue levels in the soil were determined by a lentil radicle bioassay. The duration of activity was prolonged in soil adjusted to pH 7.6 and 8.1 relative to more acidic levels. The rate of breakdown in the soil was enhanced with increased temperature and soil moisture content; a significant temperature by moisture interaction was noted over the duration of the incubation period. The dissipation of DPX-A7881 in soil obeyed first-order kinetics in both studies. An accelerated rate of breakdown in unsterilized versus sterilized soil (pH 7.6) indicated that microbial degradation was an important factor affecting the persistence in alkaline soils. Herbicide residues in the soil caused a reduction in taproot length and number of primary lateral roots of canola seedlings 15 days after planting but there were no other morphological effects observed on the root. The secondary laterals, however, had generally recovered by this time.
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Ballard, Donna, Juanita Popenoe, Bradford Bearce, and Jeffrey Skousen. "STRAWBERRY GROWTH AND DEVELOPMENT IN THREE MINESOILS AMENDED WITH SLUDGE, HARDWOOD BARK OR A SUDAN-SORGHUM GREEN MANURE CROP." HortScience 28, no. 4 (April 1993): 256D—256. http://dx.doi.org/10.21273/hortsci.28.4.256d.
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Strawberry (Fragaria × Anaassa cv. Tribute) plants were planted in 15 cm standard pots filled with overburden soils from three West Virginia surface mine sites. Initial pH levels were 6.5, 4.4, and 3.6. Prior to planting pH levels were adjusted with CaCO3 to 6.5-6.7 in each soil. Each soil was amended by mixing in 60.85 g/pot (62.5 dry kg/ha) of sewage sludge, Sudan-sorghum hybrid green manure crop, hardwood residues, or unamended. A dry fertilizer (.10-.045-,089, N-P-K) was also mixed into the soil at a rate of 0.5 g/pot (454 kg/ha). Plants were grown from 3-6 to 10-16, 1992, on which date harvests and measurements were performed. The sludge treatments significantly increased fresh and dry weight accumulation, number of leaves, leaf area, and number of runners per plant above that of the control plants. The hardwood residues amendment delayed first date of ripe fruit and decreased average fruit fresh weight in one of the soils. Hardwood residues also decreased leaf number in another soil. The pH levels were raised to 6.8-7.3 by the sludge in all soils and remained at or near these values during the growing period.
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Appleby, Arnold P. "Factors in Examining Fate of Herbicides in Soil with Bioassays." Weed Science 33, S2 (1985): 2–6. http://dx.doi.org/10.1017/s0043174500083739.
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A primary reason for studying the fate of a herbicide in soil is because of its potential effect, beneficial or detrimental, on plants. Herbicide concentrations in soil often can be accurately analyzed by chemical or physical procedures. But such quantitative measurements sometimes are not well correlated with plant response because of a number of interacting soil and environmental factors. If the question is not “How much herbicide residue is present in the soil?”, but rather “How much potential exists for herbicidal effects on plants?”, then the use of plants as one aspect of studies on herbicide persistence can be valuable. This paper addresses factors influencing the response of plants to herbicide residues under field conditions.
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Hoffman, Melinda L., Leslie A. Weston, John C. Snyder, and Emilie E. Regnier. "Separating the Effects of Sorghum (Sorghum bicolor) and Rye (Secale cereale) Root and Shoot Residues on Weed Development." Weed Science 44, no. 2 (June 1996): 402–7. http://dx.doi.org/10.1017/s0043174500094078.
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Greenhouse experiments that used capillary mat subirrigation to maintain constant soil moisture and to supply fertilizer continuously were conducted to evaluate the effects of sorghum or rye residue on early growth of barnyardgrass and velvetleaf. The separate effects of root residue and of shoot residue were compared to the combined effects of root plus shoot residues and to an uncovered soil control. Residues included as nontoxic controls were leached shoot tissue and poplar excelsior. Shoot residue, leached shoot tissue, and poplar excelsior were surface-applied on an equal light transmittance basis such that mass of poplar excelsior > shoot residue > leached shoot tissue. The presence of rye root residue delayed emergence of barnyardgrass. Surface-applied residues tended to decrease barnyardgrass height, but velvetleaf stem length was greater in treatments with surface residue. Although cover crop shoot residues had little effect on weed growth after 18 d, weed growth decreased in the presence of cover crop root residues and poplar excelsior.
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Song, Ke, Lijuan Sun, Weiguang Lv, Xianqing Zheng, Yafei Sun, William Terzaghi, Qin Qin, and Yong Xue. "Earthworms accelerate rice straw decomposition and maintenance of soil organic carbon dynamics in rice agroecosystems." PeerJ 8 (September 17, 2020): e9870. http://dx.doi.org/10.7717/peerj.9870.
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Background To promote straw degradation, we inoculated returned farmland straw with earthworms (Pheretima guillelmi). Increasing the number of earthworms may generally alter soil organic carbon (SOC) dynamics and the biological activity of agricultural soils. Methods We performed soil mesocosm experiments with and without earthworms to assess the decomposition and microbial mineralization of returned straw and soil enzyme activity across different time periods. Results When earthworms were present in soil, the surface residues were completely consumed during the first four weeks, but when earthworms were absent, most of the residues remained on the soil surface after 18 weeks. On day 28, the SOC content was significantly higher in the treatment where both earthworms and residue had been added. The SOC content was lower in the treatment where earthworms but no residue had been added. The organic carbon content in water-stable macroaggregates showed the same trend. During the first 14 weeks, the soil basal respiration was highest in the treatments with both residues and earthworms. From weeks 14 to 18, basal respiration was highest in the treatments with residues but without earthworms. We found a significant positive correlation between soil basal respiration and soil dissolved organic carbon content. Earthworms increased the activity of protease, invertase, urease and alkaline phosphatase enzymes, but decreased β-cellobiohydrolase, β-glucosidase and xylosidase activity, as well as significantly reducing ergosterol content. Conclusion The primary decomposition of exogenous rice residues was mainly performed by earthworms. Over a short period of time, they converted plant carbon into soil carbon and increased SOC. The earthworms played a key role in carbon conversion and stabilization. In the absence of exogenous residues, earthworm activity accelerated the decomposition of original organic carbon in the soil, reduced SOC, and promoted carbon mineralization.
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Dubovik, Dmitry, Elena Dubovik, Alexander Shumakov, and Bogdan Roik. "Content of macronutrients in the plant residues of winter wheat while minimizing primary tillage." BIO Web of Conferences 32 (2021): 02005. http://dx.doi.org/10.1051/bioconf/20213202005.
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As a result of the research, the influence of primary tillage practices (plowing, combined tillage, surface tillage, direct sowing) was studied on the accumulation of nitrogen, phosphorus and potassium in plant residues in the soil, in the straw and grain of winter wheat, under the conditions of chernozem soils of Kursk Region. The balance of macronutrients coming from plant residues was calculated. It was found that in the spring period in the soil layer 0-20 cm under winter wheat there was more undecayed plant residues when subsoil practices of primary tillage were used. At the same time, as the depth of tillage decreased, a large mass of plant residues was concentrated in the upper 0-10 cm layer of the soil. By the harvest period, there was an increase in the amount of plant residues in the soil by 2.96-4.62 t/ha. At the same time, the highest indicators were observed in case of plowing and direct sowing 4.62 and 4.53 t/ha, respectively. The highest reserves of nitrogen and potassium in undecayed plant residues under winter wheat in the soil were found when using direct sowing (36.0 kg/ha), those of phosphorus when plowing (10.5 kg/ha) was used in the soil layer of 010 cm. The highest mass of winter wheat straw was formed against the background of plowing (6.2 t/ha), while the content of phosphorus and potassium in it was the highest (0.26% and 1.10%, respectively). The highest yield of winter wheat grain was formed against the background of plowing (4.40 t/ha), the lowest yield was with direct sowing (3.26 t/ha). Without the use of mineral fertilizers, a negative balance of macronutrients was formed.
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Li, Shuhuan, Jie Wang, Nanxiong Gao, Lizhu Liu, and Yahua Chen. "The effects of Pantoea sp. strain Y4-4 on alfalfa in the remediation of heavy-metal-contaminated soil, and auxiliary impacts of plant residues on the remediation of saline–alkali soils." Canadian Journal of Microbiology 63, no. 4 (April 2017): 278–86. http://dx.doi.org/10.1139/cjm-2016-0369.
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The plant-growth-promoting rhizobacterium (PGPR) Y4-4 was isolated from plant rhizosphere soil and identified as Pantoea sp. by 16S rRNA sequence analysis. The effects of strain Y4-4 on alfalfa grown in heavy-metals-contaminated soil was investigated using a pot experiment. In a Cu-rich environment, the shoot dry mass and total dry mass of plants inoculated with strain Y4-4 increased by 22.6% and 21%, and Cu accumulation increased by 15%. In a Pb–Zn-rich environment, the shoot dry mass and total dry mass of plants inoculated with strain Y4-4 increased by 23.4% and 22%, and Zn accumulation increased by 30.3%. In addition, the salt tolerance and biomass of wheat seedlings could be improved by applying strain Y4-4 mixed with plant residue as a result of the Cu-rich plant residues providing copper nutrition to wheat. This study offers an efficient PGPR with strong salt tolerance and a safe strategy for the post-treatment of plant residue.
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Barnes, Clyde J., Andrew J. Goetz, and Terry L. Lavy. "Effects of Imazaquin Residues on Cotton (Gossypium hirsutum)." Weed Science 37, no. 6 (November 1989): 820–24. http://dx.doi.org/10.1017/s0043174500072908.
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Field and laboratory studies were conducted in 1987 and 1988 on several Arkansas soils to determine the effects of residual levels of imazaquin on cotton. Imazaquin concentrations ranging from 0.007 to 0.024 μg/g and 0.00 to 0.015 μg/g were found in soil samples taken 12 and 24 months, respectively, following preplant-incorporated applications at rates of 140 g/ha. Cotton yields were reduced from 7 to 42% in 1987 as the soil concentration of imazaquin increased from 0.007 to 0.024 μg/g. Imazaquin persistence was greater in clay soils than loams or sandy loams. Imazaquin was weakly adsorbed to a clay, loam, and sandy loam soil in laboratory studies; the adsorption isotherms did not differ significantly by soil texture. A bioassay utilizing cotton as the indicator species was developed to determine imazaquin concentrations in soils ranging from 0 to 0.06 μg/g. Imazaquin concentrations determined by the bioassay method were found to be 75, 77, and 80% of those determined by chemical extractions for a clay, loam, and sandy loam soil, respectively.
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Loss, Arcângelo, Marcos Gervasio Pereira, Sidinei Julio Beutler, Adriano Perin, Marisa de Cassia Piccolo, Shirlei Almeida Assunção, and Everaldo Zonta. "THE IMPACT OF AGRICULTURAL SYSTEMS IN THE SOIL ORGANIC MATTER CONTENT IN BRAZILIAN CERRADO." International Journal of Research -GRANTHAALAYAH 7, no. 8 (August 31, 2019): 220–44. http://dx.doi.org/10.29121/granthaalayah.v7.i8.2019.662.
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Were quantified the plant residues on the soil, total soil organic carbon (TOC) and nitrogen (TN) contents and the different soil organic matte (SOM) fractions and to determine 13C and 15N isotopic soil composition and plant residues in the crop–livestock integration system (CLIS), pasture and Cerrado areas, in Goias, Brazil. TOC and TN, C and N light organic matter content (C-LOM/N-LOM); C and N of particulate organic matter (C-POM/N-POM); and mineral organic matter (C-MOM/N-MOM) were evaluated. δ13C and δ15N of soil and LOM, POM, and MOM fractions, as well as the δ13C of plant residues, were also determined. Plant residues from pasture were more enriched with nutrients and C, and CLIS which are richer in N. δ13C of pasture and CLIS soils indicated that the C from the Cerrado vegetation (typically C3) was replaced by vegetation with C4 photosynthetic mechanisms. CLIS accumulated more TOC than the pasture, and provided higher C-MOM and N-MOM values than pasture, and higher N-LOM levels than pasture and Cerrado. δ13C of LOM is associated with more recent origins of carbon. δ15N of POM and soil of the CLIS and pasture indicate greater mineralization of SOM.