Dissertations / Theses on the topic 'Pasture and fodder crops'

This thesis examines the potential of nine break crops (bean, carrot, swede, hemp, sugar beet, potato, lupin, oilseed rape and linola), against an oat control crop.  Seven rotational field trails were carried out at five sites across the UK. The most profitable break crops in this study were carrot and potato in terms of direct economic return to the farmer.  Mean annual returns were £5175 and £3668 respectively.  Cereal yields following break crops were found to be more affected by the soil fertility before the break crops were planted, than the actual break crop.  Studies on the nutrient concentration of break crops showed that by the second year of the experiment, over 50% of the break crops were deficient in either N, P or K, with N deficiency being most common.  Subsequent cereal crops mostly had adequate nutrient concentrations. Break crop and cereal yields were more strongly correlated with soil nutrient concentrations at the start of the experiment that previous crop.  Root crops showed a strong N response, sugar beet had a strong Mg response, linola, oilseed rape and oat had strong K responses, and wheat and barley yields were strongly influenced by soil N, P and Cu.  In general soil nutrients decreased over the experiment as did pH and soil organic matter. In general there was an inverse relationship between the crops yield and the crop’s nutrient concentration, so as the yield of a crop increases, the concentration of nutrients in the plant matter, or quality, decrease. The break crops, hemp, linola and carrot generally had positive effects on reducing weed populations during growth and in the subsequent cereal crop compared with the control crop.  In additional these break crops were pest- and disease-free during growth.  Other break crops, such as bean, swede and oilseed rape were shown to suffer from many weed, pest or disease problems, which may limit their potential for inclusion in an organic rotation.

This study records all known legume (Leguminosae/Fabaceae) species indigenous to South Africa, Lesotho and Swaziland to establish distribution patterns and optimum climatic and soil conditions for growth. The main purpose was to propose a list of legume species for further evaluation of their pasture potential. Collection data supplied by the National Herbarium (PRE) Computerised Information System were recorded to establish the distribution patterns of species based on the bioregions vegetation map. A total of 1 654 species are known to be indigenous, representing 24 tribes and 122 genera. The grouping of legume species into five main clusters and 16 Leguminochoria is ecologically described, with the highest legume species richness found in the Northern Mistbelt Forest. Key and diagnostic species are provided for each Leguminochorion. Soil pH and mean annual minimum temperature were found to be the main drivers for distinguishing between legume assemblages. The optimum climatic and soil conditions for growth are described as well as the available descriptive attributes for species recorded. Information on the range of tolerance of most species to abiotic factors is presented. Mean annual rainfall and soil pH are highly correlated with the distribution pattern of most species, followed by mean annual minimum temperature. Legume species adapted to a wide range of soil pH levels and low soil phosphorus levels are recorded. Existing data on the cultivation and grazing or browsing status of indigenous legumes were used to select 584 species found mainly in the Central Bushveld, Mopane and Lowveld Bioregions to be further evaluated for their pasture potential. Known characteristics were used to categorise species. Species contained in the tribe Phaseoleae are of special interest since it contains most of the genera with present-day agricultural value, i.e. Eriosema, Rhynchosia and Vigna species are listed as having high potential as pasture species. This study has shown that the descriptive and distribution data accumulated by botanists (notably taxonomists) could be of beneficial use in meeting agricultural objectives. Indigenous legumes are adapted to a wide range of soil and climatic conditions and represent a valuable but largely unexploited natural resource for pasture development and soil conservation practices.<br>Thesis (PhD)--University of Pretoria, 2013.<br>gm2014<br>Plant Science<br>unrestricted

This study was conducted on the grazing of West African Dwarf (WAD) goats managed by 41 farmers in Nigeria. The study focused on the use of "fodder banks" by small-scale farmers. The objective of the research was to determine the effect of seeding Stylosanthes hamata on herbage productivity and goat performance under three grazing management systems: tethering (conventional), free grazing natural pasture or free grazing legume-seeded pasture (fodder bank).<br>Irrespective of the system of management, goats grazing the various pastures had a weaning weight of 6.0 $ pm$ 0.3 kg. At 6, 9 and 12 months the body weights were 9.3 $ pm$ 0.41, 11.7 $ pm$ 1.36 and 12.6 $ pm$ 0.73 kg, resulting from an average daily gain (ADG) of 49.0 $ pm$ 4.0, 33.4 $ pm$ 4.0, 31.0 $ pm$ 0.1 and 25.0 $ pm$ 0.03 g day$ sp{-1}$ for the growth periods of birth to 3 months (pre-weaning) 3-6, 3-9, and 3-12 month (post-weaning) growth periods, respectively. There were no significant differences among the grazing systems with regard to birth weights and 3-month body weight (weaning weight). However, during the 3 to 6-month growth period, the ADG of goats tethered on natural pasture was higher than that observed for goats grazing S. hamata seeded pasture or fenced natural pasture, but this difference disappeared with time. At the 12-month period goats grazing fodder banks were heavier than goats tethered on natural pasture during the late wet season period, but the effect was not significant. Although animals lost weight during the late rainy season, animals grazing fodder banks seemed to have lost less weight than those grazing natural pasture. (Abstract shortened by UMI.)

Made available in DSpace on 2016-01-26T18:56:21Z (GMT). No. of bitstreams: 1 Dissertacao.pdf: 149957 bytes, checksum: d219d7c38eca166d0eac355501df82ee (MD5) Previous issue date: 2009-08-28<br>The project goal was to study the productivity and quality of forage produced bromatological from monoculture of sorghum and maize and intercropping of them with dwarf pea, sunn hemp, white lupine, sunflower and radish. The experiment was installed in the area of agricultural production of the Campus II Unoeste in Presidente Prudente-SP, on April 3rd, 2008. The experimental design was a split plot with four replications, with the following treatments: monoculture of sorghum (Sorghum bicolor) and maize (Zea mays) and sorghum consortium + pigeon pea (Cajanus cajan var. Dwarf) sorghum + sunn hemp (Crotalaria juncea), Sorghum + Sunflower (Helianthus annuus), sorghum fodder radish (Raphanus sativus), sorghum + white lupine (Lupinus albus), maize + pigeon pea dwarf, corn / sunn hemp, corn / sunflower corn + radish and corn + white lupine. The plots were scaled with eight rows of sowing of six meters. Biomass were collected at 60, 90 and 120 days after sowing for the quantification of plant material and chemical analysis. Statistical analysis consists of analysis of variance and Tukey test at 5% probability to compare treatment means. The single or intercropped sorghum was more efficient during low nutritive value, especially for syndications with sunflower, hemp and pigeon, which may have occurred because plants are more adapted to the dry climate of the region. Since the time of cutting that stood out with a productive balance and quality of the composition was 90 DAS.<br>O objetivo do projeto foi estudar a produtividade e a qualidade bromatológica de forragem produzida a partir de monocultivos de sorgo e milho, bem como a consorciação dos mesmos com guandu-anão, crotalária juncea, tremoço branco, girassol e nabo forrageiro. O experimento foi instalado na área de produção agrícola do Campus II da Unoeste, em Presidente Prudente-SP, no dia 03 de abril de 2008. O delineamento experimental foi em parcelas sub-divididas, com quatro repetições, com os seguintes tratamentos: monocultivos de sorgo (Sorghum bicolor) e milho (Zea mays), e consórcios de sorgo + guandu-anão (Cajanus cajan, var. anão), sorgo + crotalária juncea (Crotalaria juncea), sorgo + girassol (Helianthus annuus), sorgo + nabo forrageiro (Raphanus sativus), sorgo + tremoço branco (Lupinus albus), milho + guandu-anão, milho + crotalária juncea, milho + girassol, milho + nabo forrageiro e milho + tremoço branco. As parcelas foram dimensionadas com oito linhas de semeadura de seis m de comprimento. Foram coletadas fitomassas aos 60, 90 e 120 dias após a semeadura para quantificação da material vegetal e análises bromatológicas. O estudo estatístico consta de análise de variância e teste Tukey a 5% de probabilidade para comparar as médias dos tratamentos. O sorgo solteiro ou consorciado mostrou-se mais eficiente na maioria das avaliações bromatológicas, com destaque para as consorciações com girassol, crotalária e guandu, fato que pode ter ocorrido por serem plantas mais adaptadas ao clima seco da região. Sendo que a época de corte que se sobressaiu com um equilíbrio produtivo e qualidade bromatológica foi a de 90 DAS.

Thesis (PhD (Forest and Wood Science))—University of Stellenbosch, 2007.<br>Sustainable livestock production in semi-arid Botswana could be improved through tree planting on-farm to provide much needed protein and shade. Such action can be encouraged if the growth, productivity, nutritional value of trees and their contribution to mass gain of livestock are known.. A study at Malotwana investigated two indigenous species, Acacia galpinii and Faidherbia albida, and two exotic species, Leucaena diversifolia and L. leucocephala, at three spacings in a randomised complete block design replicated five times. The three spacings represented 400, 317 and 241 trees per hectare. The study was conducted over 6.5 years. Indigenous trees were sampled biennially and exotics annually to evaluate crown width, height, stem diameter, stem number and stem volume index. Complete plant harvesting of exotic trees at 2.5, 4.5 and 6.5 years evaluated agroforestry production. Leaves from all four species and pods of exotic species were analysed for chemical composition. Two groups of eight lambs were balanced for mass at selection for an on-farm feeding trial. Browse from exotic trees, comprising a 2:1 ratio of pods to leaves, was fed at 30% as supplement to hay to one group whose mean mass was contrasted with that of the control group fed sorghum bran at 30%. A. galpinii was a promising species, adaptable to planting away from its origin. Its crown width ranged from 5.86 m in high density plots to 6.08 m at low density and was significantly different among stands (p = 0.0406) at 6.5 years. Diameter at breast height (dbh) was significantly different among stands aged 6.5 years (p = 0.0003) and ranged between 10.38 cm at high density to 12.48 cm in low density plots, demonstrating a capacity to provide both shade and poles on-farm. At 4.5 years, F. albida attained a mean height of 4.5 m and 4.5 cm in dbh but suffered 67% mortality during a severe drought. Annual fodder production of 0.647 and 0.996 metric tonnes ha-1 for leaves and pods of L. diversifolia and 1.237 and 1.431 for L. leucocephala was recorded in years of average rainfall. Yields of 0.3 and 0.59 metric tonnes ha-1 were recorded for both species in the driest year. Equally good agroforestry production was obtained from both low and high density stands suggesting that low density plantings, which foster higher plant survival and reduce disease incidence, are best suited to the semi-arid conditions of Botswana. The crude protein of leaves ranged between 16.26 (L. diversifolia) and 25.25% (F. albida). They were highly digestible with more than twice the calcium content livestock require. Crude protein and digestibility measures were significantly different among leaves and varied significantly at different spacings (p<0.0001). Pods of the exotic species contained significantly more protein than the leaves (p<0.0001). Lambs supplemented with browse gained 102.33 g per animal per day while the control group gained 83.95 g. There were significant differences between groups during growth (p<0.05). Growing of A. galpinii, complemented with L. diversifolia and L. leucocephala, can supply short and long term feed, and greatly enhance livestock production while diversifying farm feed sources

The association between individual plant performance and seed yield variability within and between field pea crops was investigated. In 1988/89 six F8 genotypes with morphologically distinct characteristics were selected from a yield evaluation trial. Analysis of the individual plant performance within these crops indicated an association between low seed yields and the location and dispersion of plant harvest index (PHI) and plant weight (PWT) distributions. The analyses also showed there was a strong linear relationship between the seed weight (SWT) and PWT of the individual plants within each crop, and that the smallest plants tended to have the lowest PHI values. A series of 20 simulations was used to formalize the relationships between SWT, PWT and PHI values within a crop into a principal axis model (PAM). The PAM was based on a principal axis which represented the linear relationship between SWT and PWT, and an ellipse which represented the scatter of data points around this line. When the principal axis passed through the origin, the PHI of a plant was independent of its PWT and the mean PHI was equal to the gradient of the axis. However, when the principal axis had a negative intercept then the PHI was dependent on PWT and a MPW was calculated. In 1989/90 four genotypes were sown at five plant populations, ranging from 9 to 400 plants m⁻². Significant seed and biological yield differences were detected among genotypes at 225 and 400 plants m⁻². The plasticity of yield components was highlighted, with significant genotype by environment interactions detected for each yield component. No relationship was found between results for yield components from spaced plants and those found at higher plant populations. The two highest yielding genotypes (CLU and SLU) showed either greater stability or higher genotypic means for PHI than genotypes CVN and SVU. Despite significant skewness and kurtosis in the SWT, PWT, and PHI distributions from the crops in this experiment, the assumptions of the PAM held. The lower seed yield and increased variability in PHI values for genotype CVN were explained by its higher MPW and the positioning of the ellipse closer to the PWT axis intercept than in other genotypes. For genotype SVU, the lower seed yield and mean PHI values were explained by a lower slope for the principal axis. Both low yielding genotypes were originally classified as having vigorous seedling growth and this characteristic may be detrimental to crop yields. A method for selection of field pea genotypes based on the PAM is proposed. This method enables the identification of weak competitors as single plants, which may have an advantage over vigorous plants when grown in a crop situation.

Agriculture is the principal land use throughout Europe and agricultural intensification has been implicated in large reductions in biodiversity, with the negative effects on birds particularly well documented. The lapwing (Vanellus vanellus) is one such species where changes in farming practices has reduced the suitability and quality of breeding habitat, leading to a drop in population size that has been so severe as to warrant its addition to the Red List of Birds of Conservation Concern in the UK. Lowland areas, where agricultural intensification has generally been most pronounced, have been worst affected, however, more recently declines in marginal upland areas, previously considered refuges for breeding wader populations, have been identified. An upland livestock farm in Stirlingshire that uses an in-bye system of fodder crop management and has unusually high densities of breeding lapwings provides a basis for this project to test causal hypotheses for the decline of upland lapwing populations and to identify potential conservation management solutions. Specifically this farm plants a forage brassica in an in-bye field for two consecutive years, followed by reseeding with grass and seven, out of sixteen, in-bye fields have undergone this regime at the study site since 1997. Fields that had undergone fodder crop management supported almost 60% more lapwings than comparable fields that had not previously been planted with the fodder crop. Lapwing density was highest in the year after the fodder crop was planted, once it had been grazed, which results in a high percentage of bare ground, likely to be attractive to nesting lapwings. Lapwing densities remained above that which occurred in fields that had not undergone fodder crop management for a further four years after the field had been returned to grass. The effect of management on lapwing food resources and nesting structure was tested through a field experiment; liming increased the abundance of Allolobophora chlorotica, an earthworm species that was associated with chick foraging location at the study site, suggesting that lapwings may benefit from liming conducted as part of fodder crop management. The relationship between lapwings and soil pH is further explored across 89 sites on mainland Scotland, using soil property data to improve the predictive power of habitat association models, something which has not previously been done for any farmland bird. Adding soil and topographical data to habitat models, based on established relationships between breeding lapwings and their habitat, improved model fit by almost 60%, indicating that soil properties influence the distribution of this species. The density of breeding lapwings was highest at higher altitude sites, but only when the soil was relatively less peaty and less acidic, providing further support for the hypothesis that agricultural liming benefits lapwings. In addition to assessing the conservation benefit of fodder crop management, the economic costs are also considered. Fodder crop management provides a source of livestock fodder in the autumn and winter during a period when forage demands outstrip grass growth, and ultimately improves the grazing quality of the grass that is replaced; this system currently operates outside of any agri-environment scheme (AES). However, at the study site, planting of the fodder crop and grass is delayed to avoid agriculture operations during the breeding season, which reduces yield and hence profitability. An initial estimate of £200 ha-1 is suggested as an incentive to encourage wider adoption of fodder crop management in a “lapwing friendly” manner, although further work is required to determine if this payment level is appropriate and the current method of AES implementation may limit the suitability of fodder crop management as an AES. The results indicate that agricultural liming could benefit breeding lapwings in pasture fields where soil pH falls below pH 5.2, by increasing earthworm abundance. Where soil pH is below pH 5.2, liming should provide a cost effective mechanism for farmers to improve grass yields. Regular soil testing and liming in response to low pH, within improved or semi-improved grassland fields, where management activities such as use of nitrogen fertiliser can contribute to soil acidification, should be advocated to farmers in marginal areas as a mechanism for improving grass productivity whilst potentially benefitting breeding lapwing and other species where earthworms contribute significantly to their diet.

The history of the advancement of the agricultural frontier in Brazil has been closely related to environmental losses. Although environmental losses are sometimes inevitable in the context of agricultural expansion, they should always be minimized. This study seeks to avoid the past pattern of development by proposing a more sustainable way of expanding agriculture. The research tests whether it is possible to expand the cultivation of food and fuel crops in Brazil without compromising natural ecosystems. Brazil has a great agricultural potential considering the significant amount of lands that is suitable for agriculture with a favorable climate and topography. To supply the domestic agricultural market and for Brazil to take on a global food and biofuel export leadership position, actions should be taken to plan for this potential sustainable expansion. This planning would be an alternative means of advancing the agricultural frontier, as opposed to the deforestation previously practiced. A way to accomplish a sustainable pattern of agricultural development could be by the identification of suitable areas to support the expansion without further loss of forestlands. Pasture is a type of land use that occupies large areas in Brazil, and pastures are considered strategic resources for the effectiveness of the proposed expansion, given that they represent areas that have already been deforested and offer some type of existing infrastructure. In addition, from the current biophysical potential production - pasture based beef cattle - may be underused. The goal of this dissertation is to develop a spatial allocation model based on a multicriteria decision making and geographic information systems (GIS) using land suitability analysis to support decision makers with geospatial information about where potential areas for sugarcane and soybean expansion are located in Brazil. The multicriteria decision analysis (MCDA) consists of physical land suitability, infrastructure and socioeconomic data integration to identify suitable pasturelands for crop allocation. To enhance the reliability of the model, a team of specialists in the agricultural crops was selected to establish the criteria priorities in the model for the analysis process. The combination of their judgments gives an overall priority that feeds the multicriteria model. \"What if\" scenarios were also built to show how changes in the criteria priority weights would modify the spatial distribution of suitability classes in relation to the main model. The results yield maps that represent the distribution of suitability classes for sugarcane and soybean expansion. Pasturelands become more or less suitable for sugarcane or soybean allocation according to shifts in the influence of each criterion in the model. The designed models show results that may assist policymakers with geospatial information about priority areas where investments and efforts should be directed for sustainable agricultural expansion in Brazil.<br>A história do avanço da fronteira agrícola no Brasil tem sido intrinsecamente relacionada ao desmatamento. Embora perdas ambientais sejam, por vezes, inevitáveis no contexto de uma expansão agrícola, elas devem ser reduzidas sempre que possível. Tentando não seguir um padrão de desenvolvimento feito à custa de desmatamentos, e pensando numa forma mais sustentável de expansão da agricultura, nós avaliamos nesse estudo a possibilidade de expansão agrícola, para produção de alimentos e de biocombustíveis, sem o comprometimento do ecossistema natural existente no país. O Brasil tem um grande potencial agrícola atribuído à significativa quantidade de solos aptos para agricultura com clima e topografia favoráveis. Para abastecer o mercado agrícola nacional e assumir uma posição de liderança global na exportação de alimentos e biocombustíveis, ações devem ser tomadas pelo Brasil para o planejamento desse potencial de expansão. Esse planejamento seria um modelo alternativo para o avanço da fronteira agrícola, oposto aos padrões de avanço anteriores diretamente relacionados ao desmatamento. Uma forma de conseguir um padrão de desenvolvimento sustentável poderia ser pela identificação de terras agrícolas aptas à essa expansão sem estimular maiores perdas de florestas. As pastagens ocupam grandes áreas no Brasil e são consideradas recursos estratégicos para a eficácia dessa expansão, uma vez que representam áreas que já foram desmatadas e oferecem algum tipo de infraestrutura. Dado o atual potencial biofísico de produção, estima-se que as áreas de pastagem destinadas à pecuária bovina podem estar sendo subutilizadas. O objetivo desse trabalho é desenvolver um modelo de alocação espacial fundamentado numa análise de decisão multicritério e SIG com base na aptidão agrícola das terras, de forma a fornecer informações geoespaciais estratégicas aos tomadores de decisão sobre a localização das áreas potenciais para a expansão da cana-de-açúcar e soja no Brasil. A análise de decisão multicritério (MCDA) consiste na integração de dados edafoclimáticos, de infraestrutura e socioeconômicos para a identificação das áreas de pastagens aptas para a alocação dessas culturas. Para aumentar a confiabilidade do modelo, uma equipe de especialistas em cana-deaçúcar e soja foi selecionada para julgar a prioridade das variáveis no processo de análise. A combinação dos julgamentos fornece uma prioridade geral das variáveis, as quais alimentam o modelo. \"E se\" cenários foram também elaborados para mostrar como as mudanças nos pesos dos critérios modificariam a distribuição espacial das classes de aptidão com relação ao modelo principal. Os resultados são exibidos através de mapas que representam a distribuição das classes de aptidão agrícola para a alocação dos cultivos da cana-de-açúcar e soja. As pastagens tornam-se tanto mais adequadas para a alocação da cana ou soja de acordo com as mudanças na influência de cada critério no modelo. Os modelos projetados mostram resultados favoráveis que podem ajudar os tomadores de decisão com informações geoespaciais que identificam áreas prioritárias onde investimentos e esforços deveriam ser direcionados para estimular a expansão agrícola sustentável no Brasil.

Made available in DSpace on 2014-08-20T14:33:13Z (GMT). No. of bitstreams: 1 Tese_Fernando_Pereira_Menezes.pdf: 1767639 bytes, checksum: 91a91729ef261e42fc911c10e823c7d7 (MD5) Previous issue date: 2011-12-15<br>The study was conducted in three stages, assessing the species Adesmia latifolia (Spreng.) Vog. with the aim of increasing knowledge of Adesmia responses regarding the most appropriate methods of overcoming seed dormancy, seed inoculation and production and forage quality in relation to climatic factors. The first stage was conducted at the Laboratory of Seeds Analysis FAEM/UFPEL in Pelotas, the other in the CCR/URCAMP in Bage-RS. In the work of scarification were evaluated with thermal and chemical methods to count only 14 days after sowing. Regarding the assessment of inoculant was used the following treatments: control, Bradyrhizobium spp. Rhizobium leguminosarum bv. trifolli (white clover), Rhizobium leguminosarum bv. trifolli (red clover) and Rhizobium loti (birdsfoot trefoil) in a greenhouse. The third study, conducted in the field, we evaluated the production of dry matter and forage quality, protein digestibility and in vitro. In the first work considering the three variables (normal seedlings, hard seeds and dead), the results showed that the method of soaking in hot water was more efficient in breaking dormancy of seeds of Adesmia latifolia, with emphasis on immersion in hot water at 40°C for three minutes, for issues of safety and economy. In the second study produced the highest dry matter were obtained with Bradyrhizobium spp. and Rhizobium loti, respectively, the same happened in relation to the efficiency of inoculation, with the latter being easily accessible shopping. In the third study concluded that the dry matter production is concentrated in october/november with 88% of total annual crude protein and in vitro while maintaining during the cycle with high levels.<br>O trabalho foi realizado em três etapas, avaliando a espécie Adesmia latifolia (Spreng.) Vog., com o objetivo de ampliar o conhecimento das respostas da Adesmia no que diz respeito a métodos mais adequados de superação de dormência das sementes, inoculação de sementes e produção e qualidade de forragem em relação aos fatores climáticos. A primeira etapa foi realizada no Laboratório de Análise de Sementes da FAEM/UFPEL em Pelotas-RS, as demais no CCR/URCAMP em Bagé-RS. No trabalho de superação de dormência foram avaliados métodos químicos e térmicos com contagem única aos 14 dias após a semeadura. Em relação à avaliação de inoculantes foram utilizados os seguintes tratamentos: testemunha; Bradyrhizobium spp.; Rhizobium leguminosarum bv. trifolli, (trevo branco); Rhizobium leguminosarum bv. trifolli, (trevo vermelho) e Rhizobium loti, (cornichão) em ambiente protegido. Já o terceiro trabalho, realizado a campo, foi avaliado a produção de matéria seca e a qualidade da forragem, proteína bruta e digestibilidade in vitro. No primeiro trabalho considerando-se as três variáveis (plântulas normais, sementes duras e mortas), os resultados permitiram concluir que o método de imersão em água quente foi o mais eficiente na superação de dormência de sementes de Adesmia latifolia, destacando-se a imersão em água quente a 40ºC por três minutos, por aspectos de segurança e economicidade. No segundo trabalho as maiores produções de matéria seca foram obtidas nos tratamentos com Bradyrhizobium spp. e Rhizobium loti respectivamente, o mesmo acontecendo em relação à eficiência do inoculante, sendo esse último de fácil acesso comercial. No terceiro trabalho conclui-se que a produção de matéria seca concentra-se em outubro/novembro com 88% do total anual com a proteína bruta e a digestibilidade in vitro mantendo-se ao longo do ciclo com elevados teores.

The contamination of process pea (Pisum sativum L.) crops by the immature fruit of black nightshade (Solanum nigrum L.) and hairy nightshade (S. physalifolium Rusby var. nitidibaccatum (Bitter.) Edmonds) causes income losses to pea farmers in Canterbury, New Zealand. This thesis investigates the questions of whether seed dormancy, germination requirements, plant growth, reproductive phenology, or fruit growth of either nightshade species reveal specific management practices that could reduce the contamination of process peas by the fruit of these two weeds. The seed dormancy status of these weeds indicated that both species are capable of germinating to high levels (> 90%) throughout the pea sowing season when tested at an optimum germination temperature of 20/30 °C (16/8 h). However, light was required at this temperature regime to obtain maximum germination of S. nigrum. The levels of germination in the dark at 20/30 °C and at 5/20 °C, and in light at 5/20 °C, and day to 50 % germination analyses indicated that this species cycled from nondormancy to conditional dormancy throughout the period of investigation (July to December 2002). For S. physalifolium, light was not a germination requirement, and dormancy inhibited germination at 5/20 °C early in the pea sowing season (July and August). However, by October, 100% of the population was non-dormant at this test temperature. Two field trials showed that dark cultivation did not reduce the germination of either species. Growth trials with S. nigrum and S. physalifolium indicated that S. physalifolium, in a non-competitive environment, accumulated dry matter at a faster rate than S. nigrum. However, when the two species were grown with peas there was no difference in dry matter accumulation. Investigation of the flowering phenology and fruit growth of both species showed that S. physalifolium flowered (509 °Cd, base temperature (Tb) 6 °C) approximately 120 °Cd prior to S. nigrum (633 °Cd). The fruit growth rate of S. nigrum (0.62 mm/d) was significantly faster than the growth rate of S. physalifolium (0.36 mm/d). Because of the earlier flowering of S. physalifolium it was estimated that for seedlings of both species emerging on the same date that S. physalifolium could produce a fruit with a maximum diameter of 3 mm ~ 60 °Cd before S. nigrum. Overlaps in flowering between peas and nightshade were examined in four pea cultivars, of varying time to maturity, sown on six dates. Solanum physalifolium had the potential to contaminate more pea crops than S. nigrum. In particular, late sown peas were more prone to nightshade contamination, especially late sowings using mid to long duration pea cultivars (777-839 °Cd, Tb 4.5 °C). This comparison was supported by factory data, which indicated that contamination of crops sown in October and November was more common than in crops sown in August and September. Also, cultivars sown in the later two months had an ~ 100 °Cd greater maturity value than cultivars sown in August and September. Nightshade flowering and pea maturity comparisons indicated that the use of the thermal time values for the flowering of S. nigrum and S. physalifolium can be used to calculate the necessary weed free period required from pea sowing in order to prevent the flowering of these species. The earlier flowering of S. physalifolium indicates that this species is more likely to contaminate pea crops than is S. nigrum. Therefore, extra attention may be required where this species is present in process pea crops. The prevention of the flowering of both species, by the maintenance of the appropriate weed free period following pea sowing or crop emergence, was identified as potentially, the most useful means of reducing nightshade contamination in peas.

Submitted by (edna.saturno@ufrpe.br) on 2017-05-17T15:31:54Z No. of bitstreams: 1 Marta Gerusa Soares da Silva.pdf: 1019521 bytes, checksum: dafe6a7ce15446dca593cbcc3e9179b2 (MD5)<br>Made available in DSpace on 2017-05-17T15:31:54Z (GMT). No. of bitstreams: 1 Marta Gerusa Soares da Silva.pdf: 1019521 bytes, checksum: dafe6a7ce15446dca593cbcc3e9179b2 (MD5) Previous issue date: 2010-02-26<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES<br>The aim of this study was to evaluate the dynamics of the association of „capim-de-raiz‟ (Chloris orthonoton Doell.) and „capim-milhã‟ [Brachiaria plantaginea (Link.) Hitchc.], concerning growth, persistence and production, as well to morphanatomically characterize the legume „orelha de onça‟ (Macroptilium martii Benth.). In order to evaluate the dynamics of the association „capim-de-raiz‟ and „capim-milhã‟, two experiments were carried out: I. Evaluation of deferred native pasture concerning botanical composition and forage mass; II. Growth dynamics of „capim-milhã‟ and „capim-de-raiz‟. Experiment I was conducted at the Experimental Station of IPA, in São Bento do Una - PE from 2007 to 2008 with different evaluation periods for forage mass and botanical composition. Experiment II was conducted at a greenhouse in the Animal Science Department - UFRPE, from 09.26.06 to 07.26.07. Soil blocks with the plant community were taken from native pasture area of the Experimental Station of Instituto Agronômico de Pernambuco - IPA, in São Bento do Una - PE, and placed in plastic pots remaining at a greenhouse in UFRPE. Pots were submitted to four irrigation schedules: Irrigation I - irrigation at the beginning of the experiment; Irrigation II - started two months after Irrigation I; Irrigation III - started four months after irrigation I and Irrigation IV - started six months after irrigation I. After the initial irrigation of each period, all pots were irrigated every seven days until drainage and regrowth number, seedling number, plant number and inflorescence number were evaluated. Morphanatomical characterization of „orelha de onça‟ leaf was analyzed with optical microscopy in cross-sections confectioned laminae. 10 families, 15 genera and 18 species were identified in the deferred pasture. In botanical composition from May to August 2007, „capim-milhã‟ was the main component from 60 to 90 days with 46.75 and 52.09%, respectively. In August 2007, other species participated with 57.75% of the botanical composition; at the end of evaluation in year 2008 other species occupied 100% of the composition. The highest forage mass (kg DM/ha) for „capim-milhã‟ (2.736) occurred at 90 days, for other species (3.141) and „capim-de-raiz‟ (2.701) at 120 days. In soil blocks it was observed that regrowth occurred only after 30 days of assessment for initial irrigation and the highest number of seedlings to the pots occurred at 30 days. It was observed at 60 days the largest number of grasses for irrigation III and at 90 days for irrigation IV, and that most of inflorescence appeared at 90 days. In deferred area the use of stockpiled forage should preferably take place from 60 to 90 days. The main form of establishment of „capim-de-raiz‟ was by germination and at 150 days it was observed population growth of other species. It was observed paracytic and amphistomatic stomata, simple and uniseriate hairs, palisade and spongy chlorophyll parenchyma in „orelha de onça‟ leaf blade. In stem vascular system it was observed a range of libero-ligneous beams in the internodes area, separating cortex of medulla. Foliar and stem anatomical characteristics are common to legumes.<br>O objetivo deste trabalho foi avaliar a dinâmica da associação capim-de-raiz (Chloris orthonoton Doell.) e capim-milhã [Brachiaria plantaginea (Link.) Hitchc.], quanto ao crescimento, persistência e produção, bem como caracterizar morfoanatomicamente a leguminosa orelha de onça (Macroptilium martii Benth.). Para avaliar a dinâmica da associação capim-de-raiz e capim-milhã, foram realizados dois experimentos: I. Avaliação de um pasto nativo diferido quanto à composição botânica e massa de forragem; II. Dinâmica do crescimento do capim-milhã e capim-de-raiz. O experimento I foi conduzido na Estação Experimental do IPA, no município de São Bento do Una - PE, de 2007 a 2008, sendo utilizados diferentes períodos para avaliação da massa de forragem e composição botânica. O experimento II foi realizado em telado no Departamento de Zootecnia - UFRPE, durante o período de 26.09.06 a 26.07.07. Cubos de solos com a comunidade vegetal foram retirados de área de pastagem nativa, da Estação Experimental do Instituto Agronômico de Pernambuco - IPA, no município de São Bento do Una - PE, e colocados em vasos plásticos permanecendo em telado da UFRPE. Os vasos foram submetidos a quatro épocas de início de irrigação: Irrigação I ¿ irrigação por ocasião da implantação do experimento; Irrigação II ¿ iniciada dois meses após a irrigação I; Irrigação III ¿ iniciada quatro meses após a irrigação I e Irrigação IV ¿ iniciada seis meses após a irrigação I. Após a irrigação inicial de cada período, todos os vasos foram irrigados a cada sete dias até drenagem e foram avaliados o número de rebrotes, número de plântulas, número de plantas e número de inflorescências. A caracterização morfoanatômica foliar da orelha de onça foi analisada em microscopia óptica em lâminas confeccionadas em secções transversais. Foram identificadas 10 famílias, 15 gêneros e 18 espécies no pasto diferido. Na composição botânica de maio a agosto de 2007, o capim-milhã foi o componente principal dos 60 aos 90 dias com 46,75 e 52,09%, respectivamente. Em agosto de 2007, outras espécies participaram com 57,75% da composição botânica; no ano de 2008 ao final da avaliação, outras espécies ocuparam 100% da composição. As maiores massas de forragem (kg de MS/ha) para o capim-milhã (2.736) foram aos 90 dias, e para outras espécies (3.141) e capim-de-raiz (2.701) aos 120 dias. Nos cubos de solo, observou-se que o rebrote ocorreu apenas aos 30 dias de avaliação para irrigação inicial e o maior número de plântulas para os vasos ocorreu aos 30 dias. Foi observado aos 60 dias o maior número de gramíneas para irrigação III e aos 90 dias para irrigação IV, e que a maioria das inflorescências surgiu aos 90 dias. Em área diferida, o aproveitamento da forragem acumulada deve ocorrer preferencialmente dos 60 aos 90 dias. A principal forma de estabelecimento foi por germinação de sementes e aos 150 dias observou-se crescimento populacional de outras espécies. Foram observados na lâmina foliar da orelha de onça estômatos paracíticos e anfiestomáticos, pelos simples e unisseriados, parênquima clorofiliano em paliçada e esponjoso. Nos sistemas vasculares do caule observou-se, nas áreas dos entrenós, uma faixa de feixes líbero-lenhosos separando o córtex da medula. As características anatômicas foliares e caulinares são comuns às leguminosas.

[Truncated abstract] In southern Australian farming systems the replacement of deep-rooted perennial native vegetation with shallow-rooted annual crops and pastures has resulted in rising groundwater tables and an increased incidence of dryland salinity. It has been suggested that to address this issue by restoring hydrological balance, large areas of agricultural land need to be vegetated with perennial plants. One of the most agriculturally productive ways to do this is to introduce perennial pastures, both into upslope groundwater

It analyzes the relationship between territorial dynamics in land use and changes in the hydrological regime in the Central region of Costa Rica. A comparison is made between two years and the results showed that this process has been intense from one year to another. The urban and industrial heavy pressure on the most fertile soils of the country, has led to changes inthe hydrological regime of the two major sub-basins: Virilla and Grande de San Ramón, both of which constitute the Basin of Grande de Tarcoles River. The sub-basin of the Virilla Rivercan not store rainfall, especially considering that a large percentage of its area is covered byland uses of urban type. In contrast, the sub-basin of the Grande de San Ramón River retains a higher percentage of water, having land uses dominated by pasture, crops, and forests. In synthesis, several land uses increase their area, especially urban areas, with the major exception of the forest area which was reduced considerably.<br>Se analiza la relación entre la dinámica territorial en el uso de la tierra con respecto a los cambios en el régimen hidrológico en la región central de Costa Rica. Se hace una comparación entre dos años y se encontró que tal proceso ha sido muy intenso de un año al otro. La fuerte presión urbanística e industrial sobre los suelos más fértiles del país, ha provocado modificaciones en el régimen hidrológico de las dos principales subcuencas hidrográficas: Virilla y Grande de SanRamón, ambas conforman la cuenca del río Grande de Tárcoles. La subcuenca del río Virilla no logra almacenar el agua pluvial, especialmente si se considera que un alto porcentaje de su área está cubierta por usos de tierra de tipo urbano. Por el contrario, la subcuenca del río Grande de San Ramón logra retener un mayor porcentaje de aguas, al tener usos de la tierra dominados por pastos, cultivos y bosque. En síntesis, varios de los usos de la tierra incrementan su área, en especial el área urbana, con la gran excepción del área de bosques que se redujo considerablemente.

The general goal of this research was to understand the agronomic and physiological changes of a lucerne crop in distinct physical radiation environments and to verify the potential of lucerne to grow under shaded conditions. To achieve this, the research was conducted in four main steps: (i) firstly, experimental data collection in the field using two artificial shade materials (shade cloth and wooden slats) under inigated and non-irrigated conditions; (ii) a second experiment with data collection in a typical temperate dryland agroforestry area under non-irrigated conditions; (iii) generation of a light interception sub-model suitable for shaded crops and (iv) a linkage between the light interception sub-model and a canopy photosynthesis model for agroforestry use. In experiments 1 and 2, lucerne crop was exposed to 6 different light regimes: full sunlight (FS), shade cloth (FS+CL), wooden slats (FS+SL), trees (T), trees+cloth (T +CL) and trees+slats (T+SL). The FS+SL structure produced a physical radiation environment (radiation transmission, radiation periodicity and spectral composition) that was similar to that observed in the agroforestry site (f). The mean annual photosynthetic photon flux density (PPFD) was 41 % under the FS+CL, 44% under FS+SL and 48% under T compared with FS in clear sky conditions. Plants were exposed to an intermittent (sun/shade) regime under both FS+SL and T, whereas under FS+CL the shaded light regime was continuous. The red to far-red (RIFR) ratio measured during the shade period under the slats was 0.74 and under the trees was 0.64. However, R/FR ratio increased to 1.26 and 1.23 during the illuminated period under FS+SL and T, respectively, and these were equivalent to the ratio of 1.28 observed under the FS+CL and 1.31 in FS. The radiation use efficiency (RUE) of shoots increased under the 5 shaded treatments compared with full sunlight. The pattern of radiation interception was unchanged by radiation flux, periodicity and spectral composition and all treatments had a mean extinction coefficient of 0.82. However, the magnitude of the decrease in canopy growth was less than those in PPFD transmissivity. The mean lucerne annual dry matter (DM) yield was 17.5 t ha⁻¹ in FS and 10 t ha⁻¹ under the FS+CL, FS+SL and T regimes. This declined to 3.4 t DM ha⁻¹ under T+CL (22% PPFD transmissvity) and 4.1 t DM ha⁻¹ under T+SL (23% transmissivity). A similar pattern of response was observed for leaf net photosynthesis (Pn) rates under the shade treatments compared with full sun. In addition, spectral changes observed under the trees and slats affected plant motphology by increasing the number of long stems, stem height and internode length compared with full sunlight. Thus, there were two main explanations for the increase in RUE under shade compared with full sun: (i) preferential partition of assimilates to shoot rather than root growth and/or (ii) leaves under shade were still operating at an efficient part of the photosynthetic light curve. The changes proposed for the canopy Pn model were appropriate to simulate the radiation environment of an agroforestry system. However, the model underestimated DM yields under the continuous and intermittent shade regimes. These were considered to be mainly associated with plant factors, such as overestimation in maintenance respiration and partitioning between shoots and roots in shade and the intermittency light effect on leaf Pn rates. Further investigation in these topics must be addressed to accurately predict crop yield in agroforestry areas. Overall, the lucerne crop responded typically as a sun-adapted plant under shade. It was concluded that lucerne yield potential to grow under intermediate shade was superior to most of C3 pastures previously promoted in the literature.

*‘Pasja’ (Brassica campestris x napus) and kale (Brassica oleracea var. acephala L.) were grown at Lincoln, Canterbury, New Zealand in 2008 with different levels of phosphorus (P) fertiliser. Banded or broadcast P fertiliser was applied at 0, 20, 40 and 60 kg P/ha at establishment. Total dry matter (DM) production, the proportion of the leaf and stem and leaf area development were measured over time and related to the biophysical environment. For ‘Pasja’, final DM increased with P rate from 3730 kg DM/ha to ~4900 kg DM/ha at 60 kg P/ha. For kale the increase was from 8710 kg DM/ha for the control to ~11000 kg DM/ha for all P treatments. The leaf to stem ratio declined from 22-31 at 17 days after emergence to 10.4 at the final harvest for ‘Pasja’, which meant the crop was effectively made up mainly of leaf (~90%). The ratio for kale declined from 2.7 at 24 days after emergence to 0.64 at the final harvest. The leaf to stem ratio for both species did not respond to either the method of application or rate of P. Seedling DM accumulation increased with applied P over the first 10 to 17 DAE for ‘Pasja’ and kale respectively. The crops went from shoot growth priority to root growth. The phyllochron of both species was unaffected by P application but responded linearly to the temperature above 0°C. For ‘Pasja’ the phyllochron was 60°Cd compared with 109°Cd for kale. As a consequence ‘Pasja’ developed its canopy and reached critical leaf area index (LAIcrit) earlier than kale. Leaf area index (LAI) for the control crops of both species was lower than for P fertiliser treatments with a maximum of 3.6 for ‘Pasja’ and 3.8 for kale. There was no difference in leaf area indices among the P fertiliser treatments for ‘Pasja’, while kale LAI differed with the rate of P application up to 40 kg P/ha. Total accumulated intercepted solar radiation (RIcum) was 8 and 11% greater for ‘Pasja’ and kale crops respectively when P was applied compared with the control. Thus, the difference in total dry matter yield due to P application was attributed to the difference in RIcum. Neither the method of application or rate of P applied affected the radiation use efficiency (RUE) of either crop. For ‘Pasja’ the RUE was 1.1 g DM/MJ PAR and for kale 1.33 g DM/MJ PAR. Based on this research, it was concluded that P application increased RIcum as a result of increased LAI. The difference in total DM yield was attributed to differences in RIcum. It is recommended that farmers growing ‘Pasja’ and kale under similar conditions to this experiment should apply 40 kg P/ha for ‘Pasja’ and band 20 kg P/ha for kale. *‘Pasja’ is considered both as a species and cultivar in this document as it marketed as such in New Zealand. Technically ‘Pasja’ is a leaf turnip.

This research was conducted at the University of KwaZulu-Natal, Pietermaritzburg, South Africa. The research encompasses five different studies to assess nutrient cycling in intensive and extensive grazing systems with a view to optimising livestock production. The first study was designed to assess the effect of teff-lucerne mixtures on teff, lucerne and teff-lucerne mixture yields. Lucerne and teff-lucerne mixtures benefited from the association. The overall soil N content of the teff-lucerne mixture plots was greater than the teff alone plots. The second study focused on teff-leucaena association evaluation. It had two leucaena plant row spacings as treatments, 180cm and 120cm, respectively. Teff grown in mixture with leucaena produced a total teff dry matter (DM) of 7931.57 kg ha¯¹ for the 180cm row spacing and 8329.57 for the 120cm row spacing compared to the 3548.93 kg ha¯¹ of DM obtained from the teff alone treatment. The teff-Ieucaena stand also had a greater DM yield response to leucaena row spacing compared to the teff alone. In terms of nutritive quality, all stands from the teff-leucaena plots were better than the quality obtained from the teff alone plots. Total N content of teff from the l80cm row spacing was 21.83 g kg¯¹ and that from the 120cm 16.07 g kg¯¹ compared to the total nitrogen (N) content of 19.77 g kg¯¹ of the teff alone treatment. The total phosphorus (P) content was 2.73, 1.96 and 2.07 g kg¯¹ for the 180cm, 120cm and teff alone treatments respectively. However, the total soil N content was higher for the teff alone plot than for the teff-leucaena plots, which are 1.91, 1.48 and 100 g kg¯¹ for the teff alone, 180cm and 120cm treatments respectively. The third study was designed to assess the effects of different N fertilizer application rates on teff yield response. The rates applied were 0, 50, 100 and 150 kg N ha¯¹. There was significant difference in teff response of the three N fertilizer application rates compared to the control and teff DM yield response was lower for the 150 kg N ha¯¹ (838 kg ha¯¹) treatment compared to the control (553 kg ha¯¹). Both teff DM and nutritive value were higher in the plots treated with N fertilizer than in the plot which received no N fertilizer (control). The soil N content was also higher in those plots treated with N fertilizer. Study four was conducted on the Department of Grassland Science's grassland management techniques trial field at Ukulinga. The effects of nutrient cycling under different management techniques such as burning, mowing and grazing on grass yield response, plant quality and soil nutrients were assessed. However, the response of grass DM yield and P content was not significant but the three treatments had a significant effect on grass N content. Their effect on soil N content was also significant and the grazing plot had the greatest soil N levels. The last study was conducted in the rural areas of Okhombe and Zwelitsha to assess the effects of grazing intensity on grass yield response, plant quality and soil nutrient status at different distances from homesteads. Grass DM yield and nutritive value declined when distance from the homestead increased. The soil N content also was higher nearer to the homestead than further away. Most farmers, particularly in developing countries including those in Eritrea, often experience that their animals prefer forages from some plants such as lucerne, leucaena, and other indigenous leguminous plants. They also observe that they get greater yield from crops grown near leguminous plants or in rotation with legumes. They are also still using manure from their animals to fertilize their croplands. Therefore, it is still the duty of the researchers to demonstrate to farmers on farm studies to convince farmers that it is because leguminous plants have the ability to add quality and quantity to the feed of the animals and soil nutrients to the croplands. Hopefully, this study will convey to farmers the use of growing integrated grassllegume pastures and crops, and illustrate that livestock have their own role in transporting nutrients and hence use them as good means of distributors of soil nutrients.<br>Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.

Energy and protein are the major limiting nutrients in dairy production on the small scale mixed farms in Kenya. Commercial feed supplements are expensive and therefore multipurpose fodder trees (MPT) and forage crops are advocated as the alternative supplements, because they are inexpensive, able to provide green forage even in dry season and have high protein content. These trees have tannins whose levels, seasonal and altitude distribution have not been established. Previous studies have indicated that tannins may have either beneficial effects like bloat control and increased protein bypass, or deleterious effects like the reduction feed intake and digestibility of protein in animals fed on tanniferous feed. The objectives of this study were to determine the tannin levels in the MPT, as influenced by altitude and season, and the effect of these tannins on ruminal degradation and intestinal digestion of the diet. Samples of four multipurpose fodder trees and four forage crops viz. leucaena, sesbania, gliricidia, calliandra, velvet bean, green leaf and silver leaf desmodium and cassava, were collected at Mombasa (low altitude, below 300 m ASL.) in the wet season and at Embu (high altitude, 1500 m ASL.) in both wet and dry season. Tannin and protein content were determined using gravimetric and wet oxidation nitrogen determination methods respectively. The effect of tannin on protein degradability was determined by comparing the polyethylene glycol (PEG) treated with untreated forage samples using the mobile nylon bag technique. The treated and untreated samples were incubated separately in the rumen of four Holstein cows with both rumen and duodenal cannula for 0, 6, 12, 24, 48 and 96 hours. Afterwards two sample of each species from time 12 and 24 hours were inserted into the intestine through duodenal cannula, and recovered from the feces. The dry matter (DM) and protein of samples recovered from the rumen and feces were determined and these values were fitted in anon linear regression equation P = a + b(1— ") The results indicated that the MPT had ytterbium-precipitatable tannins ranging from 16.08 (±2.39)% of the DM in Gliricidia sepium to 30.31 (±2.42)% in Desmodium. intortum. The tannin content varied significantly (P<0.05) with species. The altitude did not have significant effect on tannin content, but tannins within species behaved differently with season. The protein content differed significantly (P<0.05) with species. Proteins were significantly (P<0.05) higher in wet than in theory season. The altitude had no effect on protein content. The tannin : protein ratio also varied significantly (P<0.05) with species. Species also had a significant interaction with season. Tannins significantly (P<0.05) reduced the rumen effective degradability of both DM and crude protein in all species, resulting in large quantities of undegraded dietary nitrogen(N). Tannin also significantly (P<0.05) decreased the total tract digestion of the DM (DMD) and depressed the digestible crude protein (DCP) of leucaena, calliandra, cassava and aintortum, but had no effect on gliricidia, sesbania and velvet bean DCP. A large proportion of the rumen undegraded dietary protein that reached the intestines was degraded in most species except calliandra. Tannin significantly (P<0.05) altered the degradability constants a, b, and c for both DM and CP by reducing fraction a and the rate of degradation c and increasing the b fraction. From the study it was concluded that the MPT and forage crop species, despite their high protein content, are not good protein supplements. Their tannins reduce both the CP digestibility and the DM degradability in the rumen. Lastly, potentially viable treatments that reduce the effect of tannin on digestibility are suggested.

Cultivation of Napier grass, Pennisetum purpureum, the most important livestock crop in East Africa is severely constrained by Napier Grass Stunt (NGS) disease. The disease spreads via an insect vector or vegetative propagation of infected plant material and is caused by a phytoplasma. This necessitates the development of an integrated management approach for the disease. Therefore, objectives of this study were to assess the incidence of the disease and its severity, to identify its wild hosts and farmers‟ knowledge on these hosts, to assess the threat of NGS disease to cultivated grasses and to establish the role of wild inoculum sources in its spread. The study showed NGS incidence ranging from 33% in Uganda to 95% in Kenya with 49% of the farmers interviewed, being able to discern NGS disease by its symptoms. Most farmers cited roguing and use of alternative fodder grasses as control measures, making these strategies the likely components of an integrated management approach for the disease. Responders named Sedge grass (Cyperus spp.) and Star grass (Cynodon dactylon) as the likely hosts of diseases caused by phytoplasma. Phytoplasmas were detected in leaves of 11 of 33 wild grass species collected using polymerase chain reaction (PCR) based on the highly conserved phytoplasma-specific 16S ribosomal DNA fragment. Sequence determination of amplified PCR fragments revealed the presence of NGS-related phytoplasmas in 11 grass species, Bermuda grass white leaf (BGWL) phytoplasmas in three and goosegrass white leaf (GGWL) in two wild grass species, showing that the geographical distribution and diversity of phytoplasmas and their grass hosts are greater than previously thought. The relationships between NGS and Hyparrhenia grass white leaf (HGWL) phytoplasmas were determined using sequences based on secA gene and immunodominant protein (imp). Results showed a very low genetic diversity between NGS and HGWL and produced a phylogenetic tree congruent to that produced by the 16S, affirming the inclusion of HGWL in the 16SrXI group. NGS phytoplasma was transmissible to food crops through Maiestas banda Kramer (Hemiptera: Cicadellidae) under screen-house conditions. With 56.3%, Saccharum officinarum showed the highest infection level followed by Eleusine coracana with 50%, Sorghum bicolor with 43.8%, Oryza sativa with 31.3% and Zea mays with 18.8%. All the phytoplasma-infected plants were asymptomatic except S. officinarum plants, which showed mild to moderate symptoms consisting of foliar yellow leaves and bright white or yellow midribs. This hints that besides wild hosts, food crops may also serve as alternative source of inoculum enabling a complex NGS disease cycle, which may add to challenges in the development of the disease control strategies. However, failure by M. banda to transmit HGWL and BGWL phytoplasmas back to Napier grass is an indication that it could be the exclusive vector of NGS. Therefore, there is need to initiate transmission trials using planthoppers and leafhoppers occurring on HGWL and BGWL phytoplasma-infected grasses to determine whether insect vectors capable of transmitting phytoplasmas from native grasses to Napier grass, are present in the region.<br>PhD (Environmental Sciences), North-West University, Potchefstroom Campus, 2015

In the years 2005-2006 it was practised the analysis of plant production and the evaluation of typological structure of selected grasslands in selected farming business. It were evaluated the gualitative indices of produced roughage. It were evaluated the area sof annual crops, multi-annual fodder crops and of permanent grasslands and the produce of fodder of fodder crops and the sort and categories of stock cattle.

This dissertation thesis researches the impact of ecological conditions on the permanent graminaceous cover not faraway from the peatland in the Borkovice region. These ecological conditions primarily mean water regime of the habitat. The nutritive regime and the fodder crop value are monitored in this thesis. These data were acquired with the help of the vegetation composition, using bio-indikative methods. Resulting values are described in the thesis, and their mutual relations are also stated there. In accordance to the ascertained results, proper pratotechnic measures were proposed. These measures try to harmonize the productive and non-productive functions.

<p>Herbicide-resistant weed populations have become problematic throughout the Eastern Corn Belt, with 18 unique herbicide-resistant weed biotypes confirmed in Indiana alone. In response to these resistant populations, the agricultural chemical industry has responded by developing glyphosate-resistant crops paired with resistance to synthetic auxin herbicides such as dicamba and 2,4-D.</p><p>This research evaluates weed population shifts in cropping systems using row crops that are resistant to synthetic auxin herbicides. Identifying weed population shifts will allow future research to be targeted to weed species that would become more prevalent in cropping systems using synthetic auxin-resistant crops. The use of multiple sites of action will be needed in order to prevent weed shifts in both conventional and no-till corn-soybean production systems. Weed densities and species richness were reduced within field evaluations when six or more herbicide sites of action were implemented with residual herbicides in both corn and soybean years over a seven-year period. Additionally, soil seedbank weed densities and species richness were reduced within 2,4-D-resistant soybean production systems. Additional strategies other than the application of herbicides may be needed to manage weed populations in the future due to the high levels of herbicide-resistant weed populations in the Midwest.</p><p>Off-target movement of these synthetic auxin herbicides, has been a concern, and label-mandated buffer areas are required near sensitive areas. Investigation of whether cover crops can be an effective tactic in managing weeds in these label-mandated buffer areas was conducted. Cover crop utilization in buffer areas has not been investigated in Indiana. Additionally, termination timing is becoming more prominent as farm operators are increasingly terminating cover crops after planting. Our results demonstrate that using cover crops that utilize cereal rye and that are terminated at, or after the time of soybean planting will be beneficial in suppressing waterhemp, grasses, and sometimes horseweed within label-mandated buffer areas, but not for suppression of giant ragweed. However, delaying termination of cover crops can result in soybean yield reductions and caution should be used. Terminating cover crops with glyphosate and auxin and a residual herbicide was more effective than glyphosate alone, but would not be permitted within label-mandated buffer areas.L</p>