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1
Nigh, E. L. Jr. "Management of Rootknot Nematode in Arizona Cotton." College of Agriculture, University of Arizona (Tucson, AZ), 1989. http://hdl.handle.net/10150/204865.
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Kissock, Graham. "Biological management techniques for the potato cyst nematode." Thesis, Queen's University Belfast, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359056.
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Engelbrecht, Emil Ettiene. "Nematode (Phylum Nematoda) community assemblages : a tool to implement environmentally–sound management strategies for root–knot nematodes (Meloidogyne spp.) in potato–based cropping systems / Emil Ettiene Engelbrecht." Thesis, North-West University, 2012. http://hdl.handle.net/10394/8095.
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those special or additional educational needs and goals that would enable students to fulfil their future roles in their communities and beyond. It is also argued that the mini–education systems of non–governmental institutions could make a major contribution to solve these problems. In particular, the analysis and discussion of the mini–education system of the Foundation for Cross–Cultural Education, has demonstrated that the mini–education system of a private educational initiative can make a substantial contribution towards the educational upliftment of a community in a particular rural area.
The study provides an instrument to plan and facilitate the mini–education systems of private education initiatives working in developing communities to effect the required transformational development. To confer advice to these private educational initiatives in SSA and to address the current global concern regarding the quality of formal education, the study adapted Steyn et al.’s (2002) framework for strategic education system planning. The adapted framework guidelines can be used to increase the efficiency of all the components and elements of the particular mini–education systems functioning in developing communities. The particular strategic framework was also applied to identify and describe the needs and determinants influencing quality education in developing communities in Sub–Saharan Africa in general.
It was also found that the specific framework for strategic planning was applicable to position the mini–education system, of a particular education private initiative, in such a way that it can effectively provide in the real education needs of a particular developing community. The framework also provides valuable guidelines to educational investors, as private initiatives, and national governments that wish to integrate their education provisioning in order to improve the quality of formal education provision in SSA.Thesis (MSc (Environmental Sciences))--North-West University, Potchefstroom Campus, 2012.
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Smith, Heidi J. "Integrated management of the sugar beet cyst nematode, Heterodera schachtii." Laramie, Wyo. : University of Wyoming, 2005. http://proquest.umi.com/pqdweb?did=1095427601&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Kariuki, George Muhia. "Management of soil suppressiveness to peanut root-knot nematode using Pasteuria penetrans." [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0015716.
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Barbara, Kathryn Ann. "Management of pest mole crickets using the insect parasitic nematode Steinernema scapterisci." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0009590.
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Walker, Josephine Grobstein. "Theory and practice of parasitic nematode management at the wildlife-livestock interface." Thesis, University of Bristol, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.702875.
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Weidhuner, Amanda Marie. "Vineyard Floor Management Analysis Using Nematode Communities as a Bioindicator of Soil Health." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2402.
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Traditional vineyard floor management in the eastern USA consists of mown resident vegetation in the aisle and herbicide bare driplines, promoting soil erosion and crusting, compaction, lowered water penetration, herbicide resistance, difficult weed management, increased plant parasitic nematode populations and decreased soil biodiversity for pest management. To investigate these issues, four novel vineyard floor management techniques and two N-fertilizer applications were investigated using nematode assemblages as a bioindicator of soil health. Main-plot groundcover treatments include: 1.) grower control, consisting of mown fescue (Festuca arundinacea) in the aisle with herbicide bare vine dripline, 2.) red fescue, creeping red fescue (Festuca rubra L.) established in both the aisle and vine dripline, 3.) successional, annually planted cereal rye (Secale cereale L.), spring oats (Avena sativa L.), and sorghum-sudan grass (Sorgum x drummondii) by planting them in succession with a no-till drill throughout the year, 4.) compost treatment consisted of a 2 to 1 mix of hardwood mulch and composted winery pomace applied across both the vineyard aisle and vine dripline. Split-plot nitrogen treatments include: 1.) no nitrogen fertility applied to grapevines, 2). 20 lb. N/ac applied to grapevine dripline at budbreak, bloom and veraison. The randomized complete block design with four main-plot treatments, two split-plot treatments and five blocks was established in 2013 and 2014 in a commercial mature Norton vineyard, planted in 2003, at 2.44 x 3.66 m spacing, in southern Illinois on a Hosmer silt-loam. The canonical analysis of principle components clearly revealed that compost and successional treatments were particularly effective at shifting nematode assemblages to higher populations of cp-5 nematodes to correlate with increases in soil respiration and organic matter, thus indicating establishment of a stable soil health structure both physically and ecologically. The results of the soil health analysis panel (soil respiration, water extracted organic carbon and water extracted macro-and micro-soil elements), consistently supported the interpretation of nematode community structure analysis. In fall 2015 the compost, red fescue and successional groundcovers combined with P and K soil fertility amendments increased water extractable K (WEK) in the aisle by 85%, 59% and 71%, respectively, compared to control; they similarly increased WEK in the aisle by 46%, 59% and 71%, respectively, in summer 2016. In the dripline WEK was increased 140%, 238% and 249%, respectively, by compost, red fescue and successional treatments that received no-N-prescription, compared to the control. The application of prescription-N increased WEK by 25% and 21%, respectively, in the compost and successional treatments that had a generous mulch layer. Soil P response to groundcover treatment clearly distinguished among each treatment the impact of nutrient turnover levels with water extracted P levels: successional > red fescue > compost > control, unique to each treatment. The water extracted mineral element levels detected with the soil health analysis were one-half to one-ninth the concentration extracted with the Mehlich-III test. Red fescue tripled the population of Pratylenchus spp. (236/100cc soil) in the dripline with prescription-N fertilization compared to no-N. Red fescue and successional treatments increased Helicotylenchus spp. populations by ~657% and ~172%, respectively, compared to compost (92/100cc soil) which closely resembled control response average in the dripline across 2015 and 2016. Prescription-N reduced Longidorus spp. by 78% compared to no-N treatment (23/100cc soil) in the dripline of fall 2015. Additionally, prescription-N added to the red fescue and successional treatments reduced Xiphinema spp. populations by 57% and 92%, respectively, compared to the control (52/100cc soil). Compost and successional groundcover treatments dramatically increased grapevine yield and crop size by 38% and 30%; and 29% and 38%, respectively, compared to grower control. The prescription N-fertilizer increased yield and crop size by 13% and 17%, respectively, compared to no-N. Compost and successional also increased Ravaz index by 33% and 60%, respectively, over control without reducing vine size which indicated their future vineyard sustainability.
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Fleming, Thomas R. "Assessment and management of emerging nematode pests of Northern Ireland grassland and cereals." Thesis, Queen's University Belfast, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.695339.
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Plant parasitic nematodes (PPNs) undermine agriculture globally, through direct parasitism of crops and/or as vectors of secondary infections. The impacts are so severe and far reaching that quantifying the associated damage is virtually impossible. With the growing pressures on modern agriculture to increase productivity and to meet consumer demands, while facing limitations from increased biotic and abiotic challenge (despite slowing improvements in the development of new varietal germplasm), there is a widening gap between high yielding, high quality stock, and demand requirements. This study investigated the PPN populations in Northern Ireland agricultural land to enable identification of potential threats to plant-based agriculture systems from economically damaging species. Here, the extent of PPN diversity in Northern Irish agriculture was illustrated, with the identification of 18 different genera and the presence of statistically significant trends linking specific nematode presence and abundance with environmental and edaphic factors. Most notably, was the apparent significant increase in root knot nematode (Meloidogyne spp.) populations that were present at significantly higher incidences than those reported in the historical records. The detection of Meloidogyne minor in agricultural fields further strengthened the belief that this recently described species is in fact endemic to the British Isles. Potential nematode control management strategies were investigated and Northern Irish recommended cereal and pasture varieties were screened for the presence of naturally occurring resistance. The direct effects of several plant derived compounds and biostimulants on PPNs were investigated. Many of the compounds screened displayed attractive or repellent properties, while further analysis of ET and SA suggested Meloidogyne incognita juveniles possess memory and associative learning traits. In addition, the effects of biostimulant pre-treatment on crop plant health and resistance to nematode challenge was examined. Molecular-level impacts on the main plant defence signalling hormones (salicylate, jasmonate and ethylene) of biostimulant pre-treatment and! or 'priming' of plants during nematode challenge was assessed. Key defence related marker genes were compared at early stage infection time points (3 and 7 days post inoculation) in biostimulant pre-treated Arabidopsis thaliana.
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Cheng, Zhiqiang. "Ecology of urban lawns the impact of establishment and management on plant species composition, soil food webs, and ecosystem functioning /." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1187031808.
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Bartley, David Jon. "Prevalence, characterisation and management of anthelmintic resistance in gastro-intestinal nematodes of Scottish sheep." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/4196.
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The studies within this thesis have made a valuable contribution to our understanding of anthelmintic resistance in Scotland and in particular to the prevalence of benzimidazole (BZ) and ivermectin (IVM) resistance, the expression of multiple resistance and its management. Parasitic gastroenteritis (PGE) is a major welfare issue not only for Scottish, UK and European farmers but also for livestock producers throughout the world. Parasites such as Haemonchus, Trichostrongylus and Teladorsagia are estimated to cost the sheep industry hundreds of millions of dollars annually. To date control has largely been achieved using anthelmintics, but over reliance on anthelmintics has led to the development of multi class anthelmintic resistance (AR) and the realization that intensive chemoprophylaxis is not a sustainable approach for the control of nematodoses. The first two papers contributing to this thesis assessed the prevalence of benzimidazole (BZ) and ivermectin (IVM) resistance within ovine gastrointestinal nematode populations in Scotland. The prevalence of BZ resistance in selected Scottish lowland sheep farms was around 24% in 1991 but this had risen to over 80% by 2001. The first cases of ivermectin resistance in sheep were only detected in 2001 but a small scale survey in 2004 showed that 35% of the farms (6 from 17) surveyed had IVM resistance, with Teladorsagia and Trichostrongylus being identified as the resistant genera. The isolation of a triple class resistant T. circumcincta (MTci5) population has enabled research to focus on the important issue of the therapeutic and prophylactic management of this emerging problem. The third and fourth papers detail a series of controlled efficacy tests conducted on MTci5 that confirmed, in the short term at least, it should be possible to use a milbemycin (moxidectin; MOX) or combination treatments, with IVM and one other class of anthelmintic to control nematodoses (>90% efficacy) caused by adult and/or immature worms. However the study examining larval susceptibility highlighted the important role that immature stages can play in the selection and transmission of resistance. Currently there are no tests that can detect the presence of these resistant larval stages. The fifth paper outlines parasitological findings from the farm where MTci5 was isolated following the confirmation of multiple class resistance. Substantial efforts were made to find solutions to maintain sustainability and profitability of the enterprise though ultimately the use of MOX selected for a, predominately Teladorsagia, population against which the persistent activity of the compound was only negligible with the reappearance of eggs in faeces occurring between 21 and 28 days post treatment. Effective sustainable control of AR populations not only requires an understanding of the phenotypic and genotypic mechanisms that underpin resistance but also improved means of ensuring that our farmers are made aware of and utilize identified best practice approaches. The written and verbal responses of the farmers to questions relating to best practice advice (papers six and seven) would suggest that many of the recommendations for delaying the selection and transmission of AR (ACME, Moredun Foundation and sustainable control of parasites of sheep (SCOPS), DEFRA) are not being followed, recommendations such as the effective quarantine treatment of newly purchased animals and dosing animals at the manufacturers’ recommended dose rate were followed by only 20% and 56% of farmers respectively.
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Da, Costa Vladimir Azevedo. "Management strategies to improve soybean yield in high pH soybean cyst nematode infested fields." [Ames, Iowa : Iowa State University], 2006.
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Brady, Chad R. "Pest management for SCN bioassays and creation of new RNAI constructs for nematode suppression." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/16787.
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Master of ScienceDepartment of Plant Pathology
Harold Trick
The object of this study was to find a target sequence for the known Heterodera glycines Y25 sequence that contained no homology to any known Glycine max genes so homologous endogenous soybean gene expression will not be effected. In addition, in attempt to improve the accuracy of SCN bioassays performed in greenhouse settings, applications of a variety of insecticides with differing modes of action were applied to screen for any detectable effects on the SCN populations. The full-length sequence of the Y25 gene was blasted against the G. max genome using the National Center for Biotechnology Information blast database and a portion of the gene was found to contained no homology to the G. max genome. A rapid hairy root assay was used to screen for resistance to H. glycines. The sequence was transformed into Agrobacterium rhizogenes using a modified heat shock method. The transformed A. rhizogenes were used to inoculate soybean seedlings. The inoculated seedlings developed hairy roots expressing the target sequence. Upon finishing the hairy root assay it was discovered that there were no detectable differences across any of the treatments or the controls. It was neither proved nor disproved that the new target sequence containing no homology to the G. max genome was as effective as the original target. Further investigation will need to be conducted to show the level of control for the new target sequence.
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Menkir, Mekonnen Sissay. "Helminth parasites of sheep and goats in Eastern Ethiopia : epidemiology, and anthelmintic resistance and its management /." Uppsala : Dept. of Biomedical Sciences and Veterinary Public Health, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/200752.pdf.
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Woldemariam, Desalegn Lidetu. "Nematode prevalence, helminth management practices and anthelmintic resistance in small ruminants in the Mid-Rift Valley of Ethiopia." Thesis, University of Pretoria, 2005. http://upetd.up.ac.za/thesis/available/etd-03022006-144251/.
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Webb, Jared S. "The influence of winter annual weed control on soybean cyst nematode and summer annual weed growth and management /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1324369591&sid=3&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Tabil, Magnus Amos. "Studies on the use of Xenorhabdus spp. for the management of root-knot nematode (Meloidogyne javanica) on tomato." Thesis, University of Reading, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487485.
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The effect of cells and toxins of Xenorhabdus spp. as biological .control on root-knot nematode (Meloidogyne javanica) was investigated. The mutualist b~cteria were obtained from two entomopathogenic nematodes, Steinemema abbasi and S. riobrave originating from the United Arab Emirates and were identified to the genus level using molecular techniques and the partial 16S rRNA gene sequences were deposited with the GENBANK. The bacteria were given Accession numbers as 00186672 for Xenorhabdus sp. RUAE (fro':l Steinemema abbasl) and 00186671, 00186674 and 00186673 for Xenorhabdus sp. 119, Xenorhabdus sp.120 and Xenorhabdus sp.124 from and S. riobrave. 00186672 was closely related to X. japonica and X. nematophila while the other three were found to be same species having 100% gene sequence homology. Cells and toxins of X. bovienii, X. nematophila and Xenorhabdus sp. RUAE (00186672) proved nematoxic to M. javanica. Higher concentrations of cells and toxins were more effective in immobilisation of juveniles and suppression of hatching of eggs than the lower concentrations. At 25°C, X. nematophila inhibited more egg hatch than ?. bovienii. The four newly isolated Xenorhabdus spp. equally inhibited egg' hatch and immobilised J2. At concentration of 2x1 07 cells/ml, X. nematophila, Xenorhabdus sp. 119 (00186671) and Xenorhabdus sp.120 (00186674) completely prevented egg hatch. Cell suspensions of all the Xenorhabdus spp. used caused more than 80-90% immobilisation of juveniles. On phytotoxicity, 30min exposure of roots of tomato seedlings recorded the highest survival at concentrations of 2x107 and 4x107cells/ml. X. nematophila and Xenorhabdus sp. RUAE (00186672) when stored in compost soil for 2 months caused over 60% mortality of larvae of Gallaria mellonella. When the same bacteria were stored in sealed bottles either in a fridge (at 5°C) or on the laboratory bench for one year recorded over 60% immobilisation of juveniles of M. incognita. When used as a soil drench, all the bacteria reduced penetration of roots and production of eggs. Similar results were obtained when tomato plants were treated with bacteria as bare-root dip for 30 min. When the bacteria were applied as bare-root dip for the tomato seedlings and transplanted into soil naturally-infested with root-knot nematode, the suppression of penetration and egg formation was less effective.
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Lisonbee, Larry D. "Self-Medicative Behavior of Sheep Experiencing Gastrointestinal Nematode Infections and the Postingestive Effects of Tannis." DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/168.
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Diet selection and self-medication are fundamental to the survival of all species. The abilities to choose healthy foods in response to past consequences are basic elements of evolution. This study explores self-medication regarding tannins both as a medication and as a dietary challenge. In the first study, sheep with natural parasite infections were offered a low quality supplement containing a dose of tannins considered to be therapeutic (medicine), while the control infected lambs received the same supplement without tannins (placebo). This study included a group of parasite-free lambs. The parasitized lambs ate more of the tannin containing supplement than non-parasitized lambs for the first 12 d of the study, when parasite burdens were high, but differences became smaller and disappeared towards the end of the study when parasite burdens decreased. This result indicated lambs ability to detect the presence of internal parasites and to learn to ingest tannin when followed by relief from parasite burdens.In the second study, lambs grazed on pastures with forages containing saponins (alfalfa),iiialkaloids (endophyte-infected tall fescue) and tannins (birdsfoot trefoil). I observed the foraging behavior of groups of lambs after intra-ruminal infusions of tannins (treatment). Lambs that first received intraruminal infusions of tannins and then were offered 2-way choices between varieties of forages with high and low concentrations of either saponins, alkaloids, or tannins increased their preference for the high-saponin variety of alfalfa and the high-alkaloid variety of tall fescue relative to lambs not infused with tannins (controls). Lambs infused with tannins and offered choices among the 3 forages with high concentrations of secondary compounds also manifested higher preference for the high-alkaloid variety of tall fescue than control lambs. In contrast, lambs infused with tannin reduced their preference for the high-tannin variety of birdsfoot trefoil.This research has implications for many situations where forages with secondary compounds are available but underutilized. Landscapes where such forages are available could be used effectively with little or no harm to livestock if medicinal forages or supplements are made available and offered as alternatives so animals can learn about their benefits of chemical complementarities among different plant species.
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Deniston-sheets, Holly M. "Short Term Shifts in Soil Nematode Food Feb Structure and Nutrient Cycling Following Sustainable Soil Management in a California Vineyard." DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2021.
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Evaluating soil health using bioindicator organisms has been suggested as a method of analyzing the long-term sustainability of agricultural management practices. The main objective of this study was to determine the effects of vineyard management strategies on soil food web structure and function, using nematodes as bioindicators by calculating established nematode ecological indices. Three field trials were conducted in a commercial Pinot Noir vineyard in San Luis Obispo, California; the effects of (i) fertilizer type (organic and inorganic), (ii) weed management (herbicide and tillage), and (iii) cover crops (high or low water requirements) on nematode community structure, soil nutrient content, and crop quality and yield were analyzed. Overall, although nematode ecological indices indicated that all plots had disturbed soil food webs, the indices proved to be less useful for measuring subtle differences in soil management over the short-term than anticipated. They showed few differences treatments. In general, the most pronounced differences were seen by sample location (under the vine or in the tractor row) and sample date, rather than treatment. None of the evaluated strategies affected crop quality, although fertilizer had a slight effect on yield. However, several indices were correlated with soil chemical parameters, including pH, nitrogen, carbon, and, to a lesser extent, EC. These results indicate that while nematode indices can be useful for comparing the state of the soil food web under long-term soil conditions, they may not be a robust measure of how agricultural management practices change soil health over a single growing season.
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Acharya, Krishna. "Managing Soybean Cyst Nematode by Utilizing Cover Crops and Resistant Sources from Early Maturing Soybean Accessions." Diss., North Dakota State University, 2020. https://hdl.handle.net/10365/31636.
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Greenhouse and microplot studies were conducted for understanding the effects of cover crop species/cultivars for hosts and population reduction of soybean cyst nematode (SCN; Heterodera glycines) from the fields of North Dakota. Moreover, early-maturing soybean [Glycine max (L.)] accessions from different countries of origin were screened for resistance against two common SCN populations for finding new sources of resistance. Thirty-eight cover crop species/cultivars were evaluated for their hosting ability of two SCN populations (SCN103 and SCN2W) from two fields of North Dakota in greenhouse experiments. The majority of the tested crops were non-hosts for both SCN populations. However, a few of them, such as Austrian winter pea (Pisum sativum L.), crimson clover (Trifolium incarnatum L. cv. Dixie), crambe (Crambe abyssinica, cv. BelAnn), field pea, cvs. Aragorn and Cooper, hairy vetch (Vicia villosa Roth), turnip (Brassica rapa L. cv. Purple top), and white lupine (Lupinus albus L.) were poor-hosts/hosts of both SCN populations. Furthermore, thirteen of them were tested for the SCN population reduction either or both in the greenhouse and microplot experiments. Out of 13, at least four crops, such as annual ryegrass (Lolium multiflorum L.), brown mustard (Brassica juncea L. cv. Kodiak), daikon radish (Raphanus sativus L.), and turnip cv. Pointer showed more than 50% population reduction compared with initial population densitiy, consistently in the greenhouse or microplot experiments. The resistance screening of 152 early-maturing soybean accessions showed that a majority of the accessions were susceptible/moderately susceptible to both SCN populations (SCN HG type 0 and 2.5.7), while a few (n=18) showed good resistance responses to both or either of the SCN populations.
The cover crops, which were non-hosts/poor-hosts and have a greater ability for the SCN population reduction have great potential to be included in an integrated SCN management strategy. The novel resistant accessions identified in this study have the potential to be used in soybean breeding for developing SCN-resistant cultivars after confirming their resistance response and identifying the resistance genes/loci. The results obtained from this study helps in developing a sustainable SCN management strategy in the northern Great Plains.
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Krzyzanowski, Alaíde Aparecida [UNESP]. "Controle biológico de nematóides de galha do cafeeiro com fungos nematófagos." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/105303.
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krzyzanowski_aa_dr_jabo.pdf: 810568 bytes, checksum: f1ddd45c015fb5bb8cfd48d426c11545 (MD5)Instituto Agronômico do Paraná (IAPAR)
Os objetivos do trabalho foram isolar, identificar, comparar meios de cultura para crescimento, esporulação de fungos nematófagos e testá-los no controle de Meloidogyne exigua e M. paranaensis em laboratório, casa de vegetação e em cafezal infestado. Foram testados dois isolados de Arthrobotrys oligospora e um de Arthrobotrys sp., A. musiformis, Monacrosporium robustum e Paecilomyces liIacinus. Os dados obtidos revelaram que esses fungos ocorrem em diferentes agroecossistemas, têm exigências nutricionais especiais e apresentam diferentes níveis de predação para os nematóides estudados. Os meios, farelo de arroz, extrato de levedura e ágar, e o de fubá e ágar propiciaram crescimento e esporulação adequados para a maioria dos isolados estudados. A mistura de palha de café com farelo de arroz foi um substrato adequado para formulação desses fungos. Uma aplicação de 1 ou 2 L da mistura de partes iguais desse substrato colonizado pelos fungos, proporcionou a redução da população dos nematóides. No período estudado a cultura tratada não esboçou sinais de recuperação, indicando que cafezais depauperados, em solos degradados, não se recuperam com uma aplicação. Os dados também possibilitaram inferir que o controle biológico dos nematóides do cafeeiro será tanto mais efetivo quanto mais cedo forem iniciados os tratamentos, e a aplicação sistemática dos fungos, com isolados mais agressivos contra os nematóides presentes, deve ser efetuada.
The objective of the research was to isolate, identify and compare culture media for growth and sporulation of nematode antagonistic fungi, and to evaluate the efficiency of these agents for biological control of Meloidogyne exigua and M. paranaensis under laboratory, greenhouse and field environmental conditions. Two isolates of Arthrobotrys oligospora, one of Arthrobotrys sp. and one of each species of A. musiformis, Monacrosporium robustum and Paecilomyces liIacinus, were also evaluated. It was observed that those fungi were very common under distinct agroecosystems, having special nutrition requirements, and also different pathogenicity levels for the nematodes above related. The culture media prepared with rice meal, malt extract and agar as well as the com meal agar favoured adequate growth and sporulation of most the isolates evaluated. The mixture of coffee straw with rice meal showed to be an adequate substrate for these fungi formulation under experimental trials. Just one application of one or two liters of a mixture of equal parts of the substrate colonized by the fungi, reduced the population of nematodes. However, the treated coffee trees did not show any sign of recovery during the period of study, indicating that weak coffee trees under poor soil conditions could not recover with just one treatment. The data also show that biological control of coffee nematodes can be more effective as early as the treatment with the fungi is applied, and, considering that it is a perennial crop, the fungi systematic application along with the selection of more aggressive isolates against the nematodes, must be done.
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Krzyzanowski, Alaíde Aparecida. "Controle biológico de nematóides de galha do cafeeiro com fungos nematófagos /." Jaboticabal : [s.n.], 2006. http://hdl.handle.net/11449/105303.
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Resumo: Os objetivos do trabalho foram isolar, identificar, comparar meios de cultura para crescimento, esporulação de fungos nematófagos e testá-los no controle de Meloidogyne exigua e M. paranaensis em laboratório, casa de vegetação e em cafezal infestado. Foram testados dois isolados de Arthrobotrys oligospora e um de Arthrobotrys sp., A. musiformis, Monacrosporium robustum e Paecilomyces liIacinus. Os dados obtidos revelaram que esses fungos ocorrem em diferentes agroecossistemas, têm exigências nutricionais especiais e apresentam diferentes níveis de predação para os nematóides estudados. Os meios, farelo de arroz, extrato de levedura e ágar, e o de fubá e ágar propiciaram crescimento e esporulação adequados para a maioria dos isolados estudados. A mistura de palha de café com farelo de arroz foi um substrato adequado para formulação desses fungos. Uma aplicação de 1 ou 2 L da mistura de partes iguais desse substrato colonizado pelos fungos, proporcionou a redução da população dos nematóides. No período estudado a cultura tratada não esboçou sinais de recuperação, indicando que cafezais depauperados, em solos degradados, não se recuperam com uma aplicação. Os dados também possibilitaram inferir que o controle biológico dos nematóides do cafeeiro será tanto mais efetivo quanto mais cedo forem iniciados os tratamentos, e a aplicação sistemática dos fungos, com isolados mais agressivos contra os nematóides presentes, deve ser efetuada.Abstract: The objective of the research was to isolate, identify and compare culture media for growth and sporulation of nematode antagonistic fungi, and to evaluate the efficiency of these agents for biological control of Meloidogyne exigua and M. paranaensis under laboratory, greenhouse and field environmental conditions. Two isolates of Arthrobotrys oligospora, one of Arthrobotrys sp. and one of each species of A. musiformis, Monacrosporium robustum and Paecilomyces liIacinus, were also evaluated. It was observed that those fungi were very common under distinct agroecosystems, having special nutrition requirements, and also different pathogenicity levels for the nematodes above related. The culture media prepared with rice meal, malt extract and agar as well as the com meal agar favoured adequate growth and sporulation of most the isolates evaluated. The mixture of coffee straw with rice meal showed to be an adequate substrate for these fungi formulation under experimental trials. Just one application of one or two liters of a mixture of equal parts of the substrate colonized by the fungi, reduced the population of nematodes. However, the treated coffee trees did not show any sign of recovery during the period of study, indicating that weak coffee trees under poor soil conditions could not recover with just one treatment. The data also show that biological control of coffee nematodes can be more effective as early as the treatment with the fungi is applied, and, considering that it is a perennial crop, the fungi systematic application along with the selection of more aggressive isolates against the nematodes, must be done.
Orientador: Jaime Maia dos Santos
Coorientador: Rita de Cássia Panizzi
Banca: Marineide Mendonça Aguillera
Banca: Carlos Eduardo de Mendonça Otoboni
Banca: David Ariovaldo Banzatto
Banca: João Carlos de Oliveira
Doutor
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Van, Zyl J. (Jacques). "Occurrence, biology, damage potential and management of Heterodera Schachtii (Nematoda: Heteroderidae) in small-scale farming in the Western Cape Province, South Africa." Thesis, Stellenbosch : Stellenbosch University, 2003. http://hdl.handle.net/10019.1/53533.
Full textAbstract:
Thesis (PhD (Agric))--University of Stellenbosch, 2003.ENGLISH ABSTRACT: During a survey in the greater Cape Flats Heterodera schachtii was found to be widespread on cauliflower, Brussels sprouts, beetroot and cabbage. The numbers present were above two eggs and juveniles per gram of soil, generally regarded as the economic threshhold level of infestation and requiring control. The damage potential of H schachtii on vegetables, as well as the ability of certain weeds to serve as a source of infection on subsequent crop plantings was studied under greenhouse conditions and resulted in a reduction of yield and root weight of crops. Population densities of H schachtii increased significantly under favourable hosts like cabbage where densities of 198 eggs and juveniles per gram of soil were reached. The most commonly occurring weeds maintained nematode development and increased their population densities. They can thus serve as alternative hosts in the absence of susceptible hosts and should be routinely controlled. The life cycle and biology of H schachtii was also studied. Penetration of plant tissue and subsequent development on vegetables, weeds and trap crops were observed. Penetration was successful on all crops tested reaching 37% and 52% at inoculum levels of 22 and 11 juveniles per gram of soil, respectively. Subsequent development of H schachtii on weeds and vegetables was similar, but in the case of cauliflower and black nightshade as hosts, their life cycle was shorter in comparison to other crops. The possible existence of varying susceptibility of crops to different populations of H schachtii was examined by comparing the rates of penetration in crops and reproduction of geographically isolated populations of H schachtii in the greater Cape Flats. When root penetration, virulence and juvenile emergence were examined, populations from Lynedoch and Philippi were distinct from the other populations. Subsequently, representative individuals of these populations were subjected to PCR-RFLP, but with these techniques real differences between the various populations could not be adequately detected. The environmental parameters such as soil texture, temperature and pH on H schachtii were investigated as to their influence on the root weight and yield of crops. Reductions in the yield of beetroot and cabbage were observed with soil temperatures ranging between 15 to 30°C. Migration and penetration of H schachtii juveniles declined with an increase in clay and silt content of the soil. Above a 34% silt and clay content of soil, no migration and penetration took place. Root penetration levels of 30% and higher were reached with pH varying between 4.5 and 7.4. This resulted in a significant reduction in yield of crops. Crop rotation is an essential component of non-chemical control. In the case of H schachtii, it required one host crop in four non-host rotational cycles to maintain the population of the nematode in the soilless than three eggs and juveniles per gram of soil. The inclusion of a trap crop reduced the population densities to below two eggs and juveniles per gram of soil. It therefore also forms an integral part of a control strategy. Solarization proved successful as a physical control method. Best results were obtained in summer with clear polyethylene which led to a 97% reduction of infective juveniles. This method can be applied during the late summer in the greater Cape Flats, just before the onset of winter. This may safeguard future spring plantings. The need for effective control strategies in order to reduce the numbers of H schachtii is of the utmost importance to ensure vegetable production in the future. Small-scale farmers should therefore be educated in this respect.
AFRIKAANSE OPSOMMING: Heterodera schachtii het wydverspreid in 'n opname in die groter Kaapse Vlakte voorgekom op beet, blomkool, Brusselse spruite en kopkool. Die nematode getalle by alle lokaliteite was bo die algemeen aanvaarbare ekonomiese drempelwaarde van twee eiers en larwes per gram grond wat beheer regverdig. Die skadepotensiaal van H schachtii op groente, sowel as die vermoë van sekere onkruide om as infeksie bronne te dien vir opvolgende gewasse, is in glashuise ondersoek en het tot 'n verlaging in opbrengs en wortelmassa by gashere gelei. Die populasie digthede van H schachtii het met die aanplant van geskikte gashere tot vlakke van 198 eiers en larvae per gram grond gestyg. Die mees algemeen voorkomende gasheeronkruide het nematode ontwikkeling in stand gehou en selfs tot 'n populasie verhoging gelei. Hierdie onkruide is 'n beperkende faktor vir die verbouing van groente aangesien die onkruide as alternatiewe gasheer kan dien in die afwesigheid van gashere en onkruidbeheer moet dus op 'n gereelde basis toegepas word. Die lewenssiklus en biologie van H schachtii is ondersoek deurdat die penetrasie van gasheer wortels en die daaropvolgende ontwikkeling op groente, onkruide en vanggewasse vergelyk is. Penetrasie, vyf dae na inokulasie, is met alle gashere verkry met 37% en 52% penetrasie met inokulum vlakke van 22 en 11 larwes per gram grond onderskeidelik. Daaropvolgende ontwikkeling van H schachtii was soortgelyk op groente en onkruide, maar blomkool en nastergal het as gashere 'n verkorte lewenssiklus tot gevolg gehad. Die moontlikheid van verskille in die virulensie van H schachtii is ondersoek deur die penetrasie van gewasse en reproduksie vlakke van nematodes van nege verskillende geografies geskeide populasies in the groter Kaapse Vlakte te vergelyk. Die Lynedoch en Philippi populasies het onderskeibare resultate gelewer ten opsigte van die populasies uit die ander lokaliteite, maar geen verskille kon met PKR-RFLP aangetoon word nie. Die invloed van omgewings parameters, grondtekstuur, temperatuur en pH, is op H schachtii ondersoek ten opsigte van opbrengste en wortelmassa van gewasse. Grondtemperature tussen 15°C - 30°C het tot die grootste daling in opbrengs gelei op kopkool en beet. Migrasie en penetrasie het afgeneem met 'n toename in klei en slik inhoud tot en met 'n klei en slik inhoud van 34%, waarna geen penetrasie en migrasie voorgekom het nie. Wortelpenetrasie van 30% en hoër het voorgekom by pH vlakke van tussen 4.5 - 7.4 met die gepaardgaande verlaging in opbrengs van gewasse. Afwisseling van gewasse is 'n essensiële metode van nie-chemiese beheer van nematode getalle in die grond. Die mees optimale rotasie ten opsigte van H schachtii beheer is met die aanplanting van een gasheer gewas in vier gewas aanplantings verkry. Die insluiting van 'n vanggewas in die gewas rotasie siklus het die nematode populasievlakke tot onder twee per gram grond laat daal. Solarisasie is suksesvol uitgevoer met deurskynende poli-etileen in die groter Kaapse Vlakte gedurende die somer met gevolglik 'n 97% vermindering van die getalle infektiewe nematodes. Effektiewe beheermaatreëls ten opsigte van H schachtii moet in die groter Kaapse Vlakte ingestel word om groente-produksie in hierdie gebied te verseker. Kleinboere moet in hierdie tegnieke opgelei word.
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Mothata, Tshiamo Shilla. "Evaluation and verification of resistance in selected vegetable crops for sustainable root-knot nematode management in developing agriculture / Tshiamo Shilla Mothata." Thesis, North-West University, 2006. http://hdl.handle.net/10394/1667.
Full textAbstract:
Root-knot nematodes, (Meloidogyne species) are a major constraint in vegetable
production systems. These parasites cause high yield losses, particularly in
subsistence farming systems. This study was conducted to establish i) whether
monospecific populations of M. incognita race 2 and M. javanica were used in these
trials by means of molecular identification, ii) determine whether root-knot nematode-resistance
is present in commercially available tomato, green bean, pumpkin and
Brassica genotypes and to iii) verify resistance found. M. incognita race 2 and M.
javanica were identified as monospecific using molecular techniques. Host suitability
trials for the relevant vegetable crops were conducted in a greenhouse. Although
various nematode parameters were used (the number of eggs and 52 per root system
and per gram of roots, number of egg masses and egg-laying females (ELF) per root
system), reproduction factors values [RF = final egg and J2 numbers (Pf)/initial egg
and J2 numbers (Pi)] were used as the main criteria to select for root-knot nematode
resistance. Although substantial variation existed among the relevant vegetable
genotypes with regard to all parameters used, none of these genotypes were immune
to either M. incognita race 2 or M. javanica since these parasites reproduced on all
vegetable genotypes used in this study. However, three tomato and a range of
Brassica genotypes had W-values lower than 1, indicating resistance to M. incognita
race 2. With regard to the verification of M. incognita race 2-resistance in tomato
genotype Rhapsody relative to the susceptible Moneymaker in a microplot trial using
a range of initial inoculation levels, strong relationship existed for both genotypes for
the majority of nematode variables used. These relationships were best described by
non-linear equations. Significantly lower numbers of eggs and J2 in roots, as well as
J2 in soil were obtained for Rhapsody compared to Moneymaker. RF-values were
inversely proportional to initial population density (Pi) for Rhapsody (r = -0.3), while
it increased gradually to Pi for Moneymaker (r = 0.94). A range of Brassica genotypes
were also identified resistance to M. incognita race 2 and M. javanica, respectively,
but none of the green bean and pumpkin screened had RF-values 5 1, indicating
susceptibility to both species.Thesis (M. Environmental Science (Plant Protection))--North-West University, Potchefstroom Campus, 2007.
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Morais, Ana Caroline de Melo. "Utilização de Materiais Orgânicos como Estratégia para o Manejo da Casca Preta do Inhame." Universidade Federal de Alagoas, 2014. http://www.repositorio.ufal.br/handle/riufal/1455.
Full textAbstract:
Yam (Dioscorea spp.) is widely produced in Africa, parts of Asia, the Caribbean and tropical America. In Brazil, yam production areas are confined in the Northeast region with greatest production in the states of Pernambuco, Paraíba and Bahia. Among the constraints to yams, the dry rot disease caused by the nematodes Scutellonema bradys and Pratylenchus spp. is the most important on commercial and seed tubers. The objectives of this study were to evaluate the effect of the soil-incorporated organic amendment on the population densities of the causal agents of dry rot disease of yam, under greenhouse and field conditions. In the first experiment the above ground parts of Crotalaria juncea, C. spectabilis, C. ochroleuca, Tagetes erecta and T. patula were incorporated to the soil. Healthy sprouting yam tubers were planted and 20 days later the plants were inoculated with a mixed population of S. bradys and P. coffeae. Pots were arranged on greenhouse benches in a completely randomized design with six treatments (including the control) and eight replications. Five months after yam planting, the nematode populations were assessed. The second experiment was carried out in naturally infested field with a mixed population of P. coffeae and S. bradys, in Quebrangulo county (Alagoas state, Brazil) in a randomized block design with five treatments and five replications. The organic matter sources used as soil amendments were: coconut husk powder, castor bean cake, cow dung and chicken manure. Non amended soil was used as a control. At nine months after planting date the tubers were harvested. No control was achieved through the soil amendment in both experiments.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O inhame (Dioscorea spp.) é produzido em larga escala em países da África Ocidental, do Extremo Oriente, do Caribe e da América Tropical. No Brasil, é produzido principalmente no Nordeste. Pernambuco, Paraíba e Bahia são os principais produtores, onde são cultivadas as espécies D. cayenensis e D. alata para alimentação humana. Entre os principais problemas fitossanitários da cultura, a casca preta ou podridão seca, causada pelos nematoides Scutellonema bradys e Pratylenchus spp., destaca-se como o mais importante, incidindo em túberas comerciais e túberas-semente. Os objetivos do presente trabalho foram avaliar a influência da incorporação de materiais orgânicos ao solo sobre a densidade populacional dos nematoides causadores da casca preta. A primeira etapa do trabalho foi conduzida em casa de vegetação, no CECA/UFAL, sendo que foram incorporadas ao solo, as partes aéreas de Crotalaria juncea, C. spectabilis, C. ochroleuca, Tagetes erecta e T. patula. Após essa etapa, foi efetuado o plantio de inhame e, decorridos 20 dias, as plantas foram inoculadas com uma população mista de S. bradys e P. coffeae. O delineamento experimental foi inteiramente casualizado com seis tratamentos (incluindo a testemunha) e oito repetições. A avaliação das populações dos nematoides foi realizada cinco meses após o plantio do inhame. A segunda etapa foi realizada em campo, no município de Quebrangulo, Estado de Alagoas, onde foram aplicados ao solo naturalmente infestado com população mista de S. bradys e P. coffeae, os seguintes tratamentos: pó de coco, torta de mamona, esterco bovino, esterco de galinha, além da testemunha. O delineamento experimental adotado foi o de blocos ao acaso, com cinco tratamentos e cinco repetições. Nove meses após o plantio, foi efetuada a colheita das túberas. Os diferentes tratamentos não foram eficientes no controle da casca preta nos dois experimentos.
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CAIXETA, Larissa de Brito. "Dinâmica da nematofauna em resposta ao corte da cana-de-açúcar e fertirrigação com vinhaça." Universidade Federal Rural de Pernambuco, 2011. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6577.
Full textAbstract:
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The application of organic matter has been recognized as an efficient strategy for plant parasite nematode control, contributing for reduction of chemical products and their environmental impacts. In this context, the vinasse presents a high potential for use in alternative management of these important parasites due to the high volume of organic matter. The objectives of the present study were to evaluate nematode communities in soil and roots, correlating changes in physical and chemical soil attributes and nematode communities in function of irrigation with vinasse; evaluate the fertirrigation effect in vertical distribution of nematode communities in soil and in the spatial variability of the plant parasitic nematodes. Evaluations based on physical (soil humidity, density, porosity, granulometry, penetration resistance (MPa) and particle density) and chemical (pH, H, Al, P, Ca, Mg, Na, K and C-CO2 evolution) soil attributes and nematode community in soil and roots, carried out 30 days before and 30 and 90 days after sugarcane cut and vinasse application. There was reduction in total amount of nematode after vinasse irrigation. Soil density and Ca++ level correlated positively with the total amount of nematode and, in particular, the plant parasitic nematodes. Inversely, the organic matter correlated negatively with the free-living nematodes, plant parasitic nematodes and consequently the total amount of nematodes in soil, but presented positive correlation with endoparasites in roots. Changes in time on C-CO2 evolution were not significant neither the correlation with the taxa or trophic groups. The vertical irrigation effect on soil was signalized on Pratylenchus and Dorilamidae distribution and soil density. The higher changes in nematode densities in soil were attributed to depth, being layers of 10 and 20 cm the most crowded. According to semivariograms, endoparasite distribution fitted to spherical before and 30 days after and before vinasse application. However, ectoparasite distribution, fitted to spherical model before irrigation, shifted to exponential 30 days before vinasse application. Spatial dependence of ectoparasites was moderate after and before irrigation. Endoparasites presented moderate dependence before and weak after irrigation. At 90 days after irrigation, endo and ectoparasites did not present correlation among points sampled showing pure nugget effect.
O emprego de matéria orgânica tem sido preconizado com destacada eficiência para controle de fitonematóides, contribuindo para a redução do uso de produtos químicos e os conseqüentes impactos ao meio ambiente. Nesse contexto, a vinhaça apresenta grande potencial no manejo alternativo destes fitopatógenos, devido ao grande aporte de matéria orgânica em sua composição. Os objetivos do presente estudo foram avaliar as comunidades de nematóides no solo e raízes, correlacionando variações nos atributos físicos e químicos do solo e nas comunidades de nematóides em função da fertirrigação com vinhaça; avaliar o efeito da fertirrigação na distribuição vertical da nematofauna do solo e na variabilidade espacial dos fitonematóides. As avaliações fundamentaram-se em atributos físicos (umidade, densidade, porosidade, granulometria, resistência do solo a penetração e densidade de partícula) e químicos (pH, H, Al, P, Ca, Mg, Na, K e evolução C-CO2) do solo e caracterização da nematofauna, efetuadas 30 dias antes e 30 e 90 dias após o corte da cana e aplicação de vinhaça. Houve redução no número total de nematóides após a fertirrigação com vinhaça. A densidade do solo e o nível de Ca++ correlacionaram-se significativamente com o total de nematóides e, em particular, com os fitoparasitos. A matéria orgânica correlacionou-se negativamente com nematóides de vida livre, fitoparasitos e nematóides totais do solo, mas apresentou correlação positiva com os endoparasitos encontrados nas raízes. A evolução de C-CO2 não variou significativamente entre os períodos nem apresentou correlações com os taxa ou grupos tróficos. O efeito vertical da fertirrigação no solo foi constatado apenas nas distribuições de Pratylenchus e Dorylaimidae e na densidade do solo. As maiores variações nas densidades populacionais de nematóides no solo ocorreram nas camadas de 10 e 20 cm. A distribuição dos endoparasitos ajustou-se ao modelo esférico 30 dias antes e após a aplicação de vinhaça. Já os ectoparasitos, ajustado ao modelo esférico antes da fertirrigação, mudou para exponencial 30 dias após a aplicação de vinhaça. Os ectoparasitos apresentaram dependência espacial moderada antes e após a irrigação com vinhaça e, os endoparasitos, moderada antes e fraca 30 dias após a irrigação. Aos 90 dias após a irrigação, os endoparasitos e ectoparasitos não apresentaram correlações entre os pontos amostrados, revelando efeito pepita puro.
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Stawniak, Natalia. "Studies on stem nematode species (Ditylenchus spp.) associated with faba bean (Vicia faba L.) in the United Kingdom and their implications for field management." Thesis, University of Reading, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.578032.
Full textAbstract:
The presence of stem nematodes (Ditylenchus spp.) is a principle reason for rejecting faba bean seed for further cultivation and processing for human consumption. In the UK, annual faba bean yield losses due to the stem nematodes are estimated at between £400k and £4m per annum. A further estimated £6.25m is lost to the industry over 5 years due to the withdrawal of infested land from faba bean cultivation. Since chemical nematicides are not available and crop rotation is impractical due to the polyphagy of stem nematodes, only plant resistance offers a cost-effective and environmentally benign means of control. The present study investigates the species status of stem nematodes on faba bean in the UK in order to evaluate the level of resistance in both commercial cultivars and previously identified resistant sources of faba bean. For the first time this study has shown that D. gigas n. sp. is the predominant stem nematode species in the UK faba bean. Development of various screening methodologies has led to the efficient selection for stem nematode resistance in faba bean germplasm. Increased susceptibility was observed in spring sown genotypes, as shown by high reproduction of stem nematode, greater stem swellings and lesions. It has been demonstrated that virulence of D. gigas n. sp. increased with repeated reproduction on the susceptible genotype. Conclusively environmental conditions are shown to influence stem nematodes incidence in faba bean seeds. Increased stem nematode infestation within seeds was more pronounced in cool and humid years. This work established the differences in gene structure of endo-β-1,4-glucanases in D. gigas n. sp. and D. dipsaci sensu stricto, which are known to be a cell-wall degrading genes. Complex host-pathogen interactions have been shown by increased relative expression of dg-eng gene in planta of susceptible and resistant genotype. In continuation from this project the selected faba bean genotypes are being used in developing new cultivars with resistance to D. gigas n. sp. Understanding of the stem nematode parasitism process in relation to the development of novel approaches for control of stem nematodes is discussed.
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Lima, Fábia Silva de Oliveira. "Interferência de Pratylenchus Brachyurus em soja sob diferentes sistemas de cultivo e desempenho agronômico de cultivares de batata-doce em área infestada com Meloidogyne Incognita." Universidade Federal do Tocantins, 2015. http://hdl.handle.net/11612/577.
Full textAbstract:
Pratylenchus brachyurus tem se tornado cada vez mais frequente em campos de
soja em todo Brasil com perdas na producção estimada em 30%. Atualmente não há
relatos de cultivares de soja resistentes a P. brachyurius e as estratégias de
controles incluem rotação com culturas não hospedeiras, pousio, além do uso de
nematicidas. Este trabalho teve como objetivos avaliar a dinâmica populacional de
P. brachyurus em áreas de soja no estado do Tocantins e em áreas plantadas com
culturas de safrinha em esquema de sucessão após colheita de soja. As densidades
de P. brachyurus observadas em campos de soja em onze municípios do estado do
Tocantins variaram de 23 a 20.400 nematoides por amostras de 200 cc de solo ou
10g de raízes. Em dois locais, a média da densidade de nematoides foi maior, com
desenvolvimento menor da soja em amostras de solo e raízes tomadas dentro de
reboleiras com sintomas do nematoide, comparados com amostras de parcelas fora
das reboleiras, uma redução geral de 44,3% na altura das plantas e 39,7% no
número de vagens. Em áreas plantadas com culturas de entressafra, previamente
cultivadas com soja, incluindo milho, sorgo, milheto, crotalária, além de uma área de
pousio como tratamento, a densidade média de P. brachyurus variou entre 122 e
504 espécimes por 10g de raiz e entre 3 e 96 por 200 cc de solo. No geral, a
densidade média não diferiu estatisticamente entre as espécies testadas e todas as
culturas utilizadas no esquema de sucessão permitiu a multiplicação de P.
brachyurus. Em conclusão, o cultivo destas espécies usadas neste estudo não são
recomendadas para o manejo de P. brachyurus em campos de soja. No entanto, o uso de culturas não hospedeiras ou a utilização do sistema de pousio pode ajudar a
diminuir o nível populacional de P. brachyurus em áreas de soja.Pratylenchus brachyurus has become increasingly frequent in soybean fields throughout Brazil where yield loss assessments have reported reduction up to 30%. Currently, no soybean cultivars resistant to P. brachyurus have been identified and management strategies include crop rotation with non-host crops, fallow, and the application of nematicides. The goals of this study were to examine the population dynamics of P. brachyurus in soybean fields throughout Tocantins state and in areas planted with off-season crops following soybean harvest in a crop succession scheme. Pratylenchus brachyurus was present in ca. 82% of samples with densities in soybean fields ranging from 23 to 20,400 nematodes per 200 cm3 soil or 10g root samples. In two sites, the mean nematode density was higher within infestation foci which were characterized by poor soybean growth compared to those from outside infestation foci, with an overall reduction of 44.3% in plant height and 39.7% in pod numbers. Following soybean harvest in areas planted with off-season crops including maize, sorghum, millet, crotalaria as well as an area maintained as a fallow treatment, the mean density of P. brachyurus ranged from 122 to 504 individuals per 10 g root sample and from 3 to 96 per 200 cm3 soil. Overall, the mean density of nematodes did not differ significantly among plant species and all crops used in the succession scheme allowed P. brachyurus multiplication. In summary, off-season cultivation with the crops used in this study is not recommended for management of P. brachyurus in soybean, but the use of fallow or non-hosts may be helpful in lowering the population density of P. brachyurus in soybean fields.
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Kühnhold, Volker [Verfasser]. "Investigation on host-parasite interaction between the stem nematode Ditylenchus dipsaci and sugar beet Beta vulgaris and their importance for development of alternative integrated management strategies / Volker Kühnhold. Landwirtschaftliche Fakultät." Bonn : Universitäts- und Landesbibliothek Bonn, 2011. http://d-nb.info/1017217483/34.
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Mohotti, Keerthi Meepe. "Non-chemical approaches for the management of the root lesion nematode, Pratylenchus loosi Loof, 1960 in tea (Camellia sinensis (L.) O. Kuntze) : with special reference to use of endospore-forming bacterium, Pasteuria penetrans." Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265105.
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Anastasiadis, Ioannis A. "Sustainable management strategies for root-knot nematodes (Meloidogyne spp.)." Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436608.
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The work presented in this thesis evaluated the potential of integrated management of root-knot nematodes. Emphasis was given to the use of two complementary biological control agents, Paecilomyces lilacinus and Bacillus firmus, together with appropriate cultural practices including soil solarization and organic soil amendments, in comparison with the judicious use of chemical control. Use of soil amendments for nematode population suppression, demonstrated that application of fresh-chopped grass and brassicacaeous amendments suppressed root-knot nematode populations. After incubation of soil for 2 weeks in plastic covered pots, the addition of broccoli, cauliflower and cabbage at 10 kg/m2 reduced the number of females in roots by 69, 45 and 39.5% respectively. Volatiles from grass, broccoli and Vapam reduced the number of females in roots by 32, 40.5 and 100% respectively, in plastic covered pots after incubation of amended soil for 1 week. In field experiments, at the end of the cropping season, significantly more nematodes parasitized the roots in control plots compared with those treated with B. firmus with and without soil solarization. Soil solarization alone or in combination with P. lilacinus provided efficient control of root-knot nematodes in comparison with the untreated control. No significant additive of synergistic interactions occurred between soil solarization and P. lilacinus. Attempts to enhance soil suppressiveness to root-knot nematodes through inundative applications of different inoculum densities of P. lilacinus and B. firmus, singly or together, were successful. There is some evidence that time may be an important factor in determining the activity of these biocontrol agents.
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Hockland, Sue. "A pragmatic approach to identifying Aphelenchoides species for plant health quarantine and pest management programmes." Thesis, University of Reading, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250716.
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The genus Aphelenchoides consists of over 140 nominal species, some of which are pathogenic to plants. Nematologists in statutory and other diagnostic laboratories need to be able to distinguish pathogens with confidence if financial losses and unnecessary chemical control are to be avoided, but no complete key to this genus has been available to date. A revised list of species was produced, deleting descriptions considered too poor for subsequent recognition. Key diagnostic characters were identified and promising features for future diagnostic use were investigated. A polytomous key (polykey) was developed and tested on 14 populations. The findings contributed to a further reduction in the number of valid species from a diagnostician's point of view, and also led to revisions of the polykey itself as key characters were tested for their distinguishing power. The primary key characters were identified as the length of the post-vulval sac (pvs) as a percentage of the distance between the vulva and the anus, the shape of the tail terminus and tail, body length, and the ratios `a' (body length divided by greatest body width) and `c' (body length divided by tail length). Promising key characters for the future are c' (tail length divided by body width at the anus or cloaca), the distance from the vulva to the anus, vulval body width, pvs length as a measure of the vulval body width, head width and all measurements associated with the median bulb. The polykey provides the essential foundation for the development of new diagnostic tools, including new keys for diagnostic use; preliminary work with molecular techniques showed promise for inclusion in diagnostic protocols, but further study will be required to develop reliable methodology for each of the economically important species. Nominators of new species should use the recording form to provide details of morphological and morphometric characters and compare resulting polycodes with others in the polykey and associated databases before publication. Likewise, the key should continue to be tested for its validity.
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Ramirez, Ricardo A. "Entomopathogen efficiency against Colorado potato beetle in diverse management systems." Online access for everyone, 2008. http://www.dissertations.wsu.edu/Dissertations/Spring2008/R_Ramirez_042108.pdf.
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Luc, John Eric. "Effects of plant parasitic nematodes and nitrogen fertility management on hybrid bermudagrass." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0004412.
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Adiko, Amoncho. "The hyperparasite Pasteuria penetrans and the management of root-knot nematodes (Meloidogyne spp.)." Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384869.
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Missah, Augustus. "Parasitic nematodes and fungi associated with yam : distribution, interactions and management in Ghana." Thesis, University of Reading, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343329.
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Vouyoykalou, E. "Possible non-chemical methods for the management of root-knot nematodes (Meloidogyne spp)." Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259493.
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Hasna, Mahbuba Kaniz. "Corky root disease management in organic tomato production : composts, fungivorous nematodes and grower participation /." Uppsala : Dept. of Crop Production Ecology, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/2007114.pdf.
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Weekes, C. Sherman. "The integrated management of root knot nematodes in the Leeward Islands of the Caribbean." Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263065.
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Karanja, Daniel Kimani. "Studies on integrated management of root-knot nematodes (Meloidogyne spp.) on tomato in Kenya." Thesis, University of Reading, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408105.
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Neilson, Roy. "Trophic inter-relationships between soil invertebrates and plants investigated using stable isotope natural abundances." Thesis, University of Dundee, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327546.
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Weeks, Brian, and Paul Baker. "Subterranean Termite (Isoptera: Rhinotermitidae) Mortality Due to Entomopathogenic Nematodes (Nematoda:Steinernematidae, Heterorhabditidae)." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2004. http://hdl.handle.net/10150/216530.
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Two species of entomopathogenic nematode were studied in terms of their survivability, detectability by the subterranean termite Heterotermes aureus, and their ability to induce mortality in H. aureus. Heterorhabdidtis bacteriophora (Poinar) and Steinernema carpocapsae (Weiser) are nematodes sold commercially as a means of biological control for termites. We used a laboratory method to determine how effective these nematode species might be under field conditions. Tests showed a difference in the survivability between nematode species and also ability to kill termites. It was also shown that H. aureus had no ability to detect either nematode species when given a choice between arenas infested with nematodes and not. Though nematodes might have some limited capacity for termite control, those considering using nematodes to control Heterotermes aureus may want to consider the species of nematode before making a purchase.
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Escudero, Benito Nuria. "Rhizomodulation for tomato growth promotion and management of root knot nematodes using Pochonia chlamydosporia and chitosan." Doctoral thesis, Universidad de Alicante, 2015. http://hdl.handle.net/10045/63467.
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Schroer, Sibylle. "Foliar application of entomopathogenic nematodes for integration in a biological control management against Plutella xylostella (Lepidoptera; Plutellidae)." [S.l.] : [s.n.], 2004. http://e-diss.uni-kiel.de/diss_1410/d1410.pdf.
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Van, Zyl Erika A. "The potential of Lespedeza cuneata as bio-active forage in the management of gastrointestinal nematodes in sheep." Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/46042.
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The rapid increase in the magnitude of anthelmintic resistance towards commercial chemical anthelmintics, calls for alternative methods to complement treatment or replace anthelmintics. During the last two decades more and more calls have been made for a holistic management solution. Recent studies on breeding for resistant animals and bioactive forages highlight the potential of these to contribute towards parasite control.
For this study, gastrointestinal infection in a merino flock was investigated by means of faecal egg counts (FEC). The level of parasite infection in weaned merino lambs in their first summer could be linked to weather conditions. Anthelmintic resistance in the flock was quantified and compared to the resistance level some years earlier. Within the flock, 18% of the ewes appeared to be resistant with consistently (P<0.05) lower FEC than the rest of the flock.
Lespedeza cuneata, a tannin-containing legume, is, according to scientific literature, one of the promising bioactive forages. Depending on the level of condensed tannin (CT), ruminant digestion can be complemented or compromised by the tannins. Small plot trials were conducted to establish production criteria for L. cuneata, currently lacking in South Africa. The grand mean dry mass (DM) yield for the first growing season, (characterized by above normal rainfall), was 8.3 t ha-1, compared to the 2.56 t ha-1 for the second growing season, (characterized by below normal rainfall). Highly significant differences (P<0.001) were measured between the yields produced under different cutting frequencies (6, 8 and 12 weeks) and cutting heights (5 cm and 15 cm). Except for crude protein levels, ADF (acid detergent fibre) and NDF (neutral detergent fibre) analysis of the complete plant indicated a less acceptable nutritional quality. Since sheep selected leaves during grazing, separated leaf samples were analysed. Chemical feed analyses of leaves were more favourable, compared to feed analysis of the whole plant. The condensed tannin (CT) content of leaves increased significantly (P<0.05) with increased moisture stress and varied between 24.5 and 122 g kg-1 DM over the growing seasons. Different dried herbage diets were offered to Merino ewes in a follow-up trial to evaluate the anthelmintic properties of the forage. The leaf portion of Lespedeza cuneata hay and Medicago sativa hay was offered ad libitum to confined sheep. Lespedeza cuneata is a tannin rich legume, while Medicago sativa, known for its very low tannin content, was used as control. FEC were significantly (P<0.05) lower in the Lespedeza group after 35 days.
To determine the influence of condensed tannin (CT) level on the hatch efficacy of Haemonchus contortus eggs, acetone leaf extracts of L. cuneata plants with different condensed tannin contents (73.5, 88, 102 and 122 g kg-1 DM) were tested in an in vitro assay on H. contortus eggs. Concentrations of between 0.63 and 20 mg ml-1 were used in the assay. Concentrations higher than 10 mg ml-1 led to complete inhibition of egg hatching with all the plant extracts regardless of CT content. A typical dose related response of the extracts of plants with very high tannin content was found, but not with plant extracts containing lower tannin concentrations.
The results of the study indicate that L. cuneata can be incorporated in a fodder flow programme as an alternative or complementary strategy to other methods, to manage the detrimental effect of gastrointestinal parasites in sheep.Dissertation (MSc)--University of Pretoria, 2014.
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Paraclinical Sciences
MSc
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Steenkamp, Sonia. "Host plant resistance as a management tool for Ditylenchus africanus (Nematoda: Tylenchidae) on groundnut (Arachis hypogaea) / Sonia Steenkamp." Thesis, North-West University, 2008. http://hdl.handle.net/10394/2299.
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Addae, Richard A. "Integrated management of root knot nematodes on vegetables in Ghana using biological control agents, amendments and crop rotation." Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270321.
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Meressa, Beira Hailu [Verfasser]. "Distribution, Population Dynamics and Sustainable Management of Plant-Parasitic Nematodes Associated with Cut-Flowers in Ethiopia / Beira Hailu Meressa." Bonn : Universitäts- und Landesbibliothek Bonn, 2014. http://d-nb.info/1077268939/34.
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Daniel, John Sathiaseelan. "Strategies for the management of root-knot nematodes with biocontrol agents and crop rotations for vegetable crops in small farms." Thesis, University of Reading, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402591.
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Heard, Edward. "Establishment of blackberries and detection and management of raspberry crown borer." Master's thesis, Mississippi State : Mississippi State University, 2006. http://library.msstate.edu/etd/show.asp?etd=etd-12012006-133945.
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