Thesis (M.Sc. (Pasture Science)) -- University of Limpopo, 2022 / In South Africa, livestock production is a rapidly growing business in the agricultural sector contributing up to 46.9% of the gross domestic value. The shortage of adequate, good quality forage during the winter months is one of the biggest problems confronting livestock farmers in the Limpopo Province. This study was initiated in 2019 to evaluate the production potential and nutritive value of different summer annual forage legumes, namely sunnhemp (Crotalaria juncea), forage cowpea (Vigna unguiculata), lablab bean (Lablab purpureus), and pigeon pea (Cajanus cajans), and their impact on succeeding winter stooling ryegrass (Secale cereale), at the University of Limpopo experimental farm Syferkuil and a Cooperative farmers’ field at Ofcolaco. The study was evaluated in a randomized complete block design with four replications. Dry matter yield, crude protein, crude protein yield, leaf chlorophyll content, Normalized Difference Vegetative Index (NDVI), and leaf gaseous exchange parameters of forage crops were statistically analysed with Statistical Analysis System (SAS), Enterprise Version 9.4, using the least significant difference (LSD) method for mean comparison. Pigeon pea biomass accumulation was 57% lower than the average of the three other legumes at Syferkuil. Sunnhemp produced superior biomass (P<0.05) compared to the other three species, reaching a peak yield of 3142.4 kg.ha-1 and 8970.8 kg ha-1 at Syferkuil and Ofcolaco, respectively. Cowpea and lablab produced similar biomass at Syferkuil. The crude protein content of the forage species ranged from 22.91% to 26.82% at Syferkuil and 17.03% to 23.84% at Ofcolaco. Leaf chlorophyll content differed (P<0.001) among the forage legume species at both locations with cowpea producing the highest chlorophyll content at Syferkuil, whereas at Ofcolaco, pigeon pea constantly produced the highest chlorophyll compared to other species. Pigeon pea was the only species rated moderately healthy with Normalised Difference Vegetative Index (NDVI) readings at Syferkuil, unlike at Ofcolaco where all forage legumes were rated as very healthy. At Syferkuil, no root nodules were observed among all the forage legumes at all sampling dates but at Ofcolaco, nodules were produced at 44 DAE with cowpea producing the highest, 92.32% higher than the average of sunnhemp, lablab, and pigeon-pea. At this location pigeon pea did not nodulate. The transpiration rate at Syferkuil was significant (P<0.01) among the species starting with a low transpiration rate from 24 days after planting and reaching their peak at 66DAE. Overall, pigeon pea had the highest (P<0.05) mean transpiration rate compared to the other species. At Ofcolaco the forage legume treatment did not have any significant (P>0.05) influence on transpiration rate, stomatal conductance and sub-stomatal conductance. The transpiration rate of the species ranged from 0.1 mol m-2 s -1 to 5.15 mol m-2 s -1 across all sampling dates whereas stomatal conductance ranged from 0.06 to 5.59 mol m-2 s -1 at Syferkuil and 0.1 to 5.15 mol m-2 s -1 at Ofcolaco, across all sampling dates and species. At Syferkuil, the mean stomatal conductance values ranged from 129.75 mol m-2 s -1 to 374 mol m-2 s -1 across the sampling dates and species, whereas, at Ofcolaco, the means ranged from 185 mol m-2s -1 to 390.25 mol m-2s -1 . The succeeding stooling rye produced a similar biomass yield under every preceding forage legume. This can be concluded that all the four forage legumes did not have any effect on the biomass production of stooling rye. However, there appeared to be a tendency of higher biomass production in the grass species grown after pigeon pea and lablab compared to those following sunnhemp and cowpea. Further experiments are required to establish the full benefits of the forage legumes on succeeding forage grass crop. Based on the results from this study, it was concluded that sunnhemp can be considered as the first choice forage legume at both Syferkuil and Ofcolaco due to its consistently high biomass production, comparable nutrient profile, high crude protein content and high protein yield compared with the other legumes. Though sunnhemp was superior, the other forage summer legumes species studied also managed to produce enough biomass for grazing and had similar nutritive value which was above minimum recommendations. They can therefore be cultivated in the province to meet the constraint of the feed gap in the province. Additional studies at different locations, however, will help to understand the productivity of the species and also to establish the full benefits of the forage legumes on succeeding forage grass crops / National Research Foundation (NRF) and Department of Science and Innovation

The operation of biogas plants solves environmental aspects (energy management, reduction of negative impacts on the environment, use of renewable energy sources) and their influence in connection with the production of acidogenic (solid) as well as methanogenic (liquid) digestate. This requires establishing mandatory solution procedures in terms of the current legislation (air protection, use of fertilizers). The research for the thesis was carried out in the Agricultural and Commercial Cooperative in Kámen (in the region of Havlíčkův Brod), which lies 527 metres above the sea level. A biogas station has been operated by the cooperative since 2011. In addition to biogas, the cooperative also utilizes the fermentation remnants separated methanogenic digestate as a fertilizer and acidogenic digestate as a raw material for the production of compost. The thesis examined the use of methanogenic digestate when growing silage maize. During the one-year research, two maize hybrids and their response to fertilization by methanogenic digestate were assessed. Both hybrids achieved a higher yield of biomass and a higher yield of the dry matter.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Swine production in southern Brazil is concentrated on small farms, seeking the recovery of waste as a source of nutrients crops of economic interest. The interaction between applications of pig slurry and soil management is common on small farms, however scarce information was found about the main responses of agricultural crops under this condition. Thus, the present work aimed to evaluate the use of pig slurry, associated with soil management in succession oat / maize and double purpose wheat / soybean. The experimental design was a factorial in a randomized complete block design, with four replications. The treatments consisted of doses of pig slurry (without manure, 20, 40, 80 m3 ha-1), and mineral fertilizer in three different soil management: no tillage, chiseling and chiseling + disking. The application of pig slurry was held before oat/maize and wheat crops sowing, and the soil management employed only before the establishment of winter crops. The application of pig slurry in succession oat / maize showed increases in dry matter yield, and in the accumulation of nitrogen, phosphorus and potassium, and in the grain yield. As for soil management, no-tillage favored the production of oat dry matter yield and soybean grain yield. However, the dual-purpose wheat proved to be low responsive to soil management employed. As for maize, the interaction between higher doses of pig slurry and with tillage managements promotes increases in grain yield. The application of pig slurry before the dual purpose wheat sowing promoted increases in dry matter production and grain yield. The residual effect of five applications of pig slurry does not alter the soybean grain yield. / A produção de suínos no Sul do Brasil concentra-se em pequenas propriedades rurais, que buscam o aproveitamento dos resíduos como fonte de nutrientes as culturas agrícolas de interesse econômico. Aplicação de dejeto líquido de suínos e manejos de solo diferenciados é comum em pequenas propriedades rurais, no entanto são escassas informações sob as repostas das principais culturas agrícolas frente a esta condição. Nesse sentido, o trabalho teve por objetivo avaliar a influência do uso de dejeto líquido de suínos, associado a manejos de solo na sucessão aveia/milho e trigo duplo propósito/soja. O delineamento experimental foi de blocos ao acaso em esquema fatorial, com quatro repetições. Os tratamentos constaram da interação de doses de dejeto líquido de suínos (sem dejeto, 20, 40, 80 m3 ha-1), e adubação mineral, em três diferentes manejos de solo: plantio direto, escarificado e escarificação + gradagem. A aplicação do dejeto líquido de suínos foi realizada antes da semeadura das culturas aveia, milho e trigo, os manejos de solo realizados antes do estabelecimento das culturas de inverno. A aplicação de dejeto líquido de suínos na sucessão aveia/milho promoveu incrementos na produção de matéria seca, no acúmulo de nitrogênio, fósforo e potássio, e na produtividade de grãos. Quanto aos manejos de solo, o plantio direto favoreceu a produção de matéria seca da aveia e a produtividade de grãos de soja. Já para o milho, a interação entre maiores doses de dejeto líquido de suínos e manejos com revolvimento do solo promove incrementos na produtividade de grãos. A aplicação do dejeto líquido de suínos antes da semeadura do trigo duplo propósito promove incrementos na produção de matéria seca e na produtividade de grãos. O efeito residual de cinco aplicações de dejeto líquido de suínos não altera a produtividade de grãos de soja.

Os objetivos do estudo foram avaliar os efeitos do intervalo entre cortes e da estação do ano, sobre a produção de matéria seca (MS), composição morfológica e químico-bromatológica do capim-Marandu. Os tratamentos consistiram em seis intervalos entre cortes (T15, T30, T45, T60 T75 e T90), com forragens colhidas, respectivamente, aos 15, 30, 45, 60, 75 e 90 dias de rebrotação, conduzidos ao longo de 12 meses. Parte da forragem colhida foi ensilada em janeiro (verão) e julho (inverno), exceto T75. Foram realizados dois ensaios, no primeiro houve a caracterização da produção de MS, composição morfológica e químico-bromatológica da forragem. Num segundo ensaio foi caracterizada a composição químico-bromatológica das silagens de capim-Marandu e foram avaliados alguns parâmetros físicos das mesmas, como densidade da massa verde (DMV), da massa seca (DMS), tamanho médio das partículas, condutividade elétrica (CE) e atividade de água (Aw). O processo fermentativo foi avaliado indiretamente através da quantificação das perdas por gases, produção de efluente e taxa de recuperação de MS das silagens. O delineamento experimental constituiu-se de blocos completos casualizados avaliando seis tratamentos para o primeiro ensaio e cinco no segundo. Para o ensaio de produção e qualidade da forragem os dados foram agrupados em ciclos de cortes de 90 dias para efeito de comparação entre os tratamentos. As produções de MS nos tratamentos T30 e T45 (21 t ha -1 ano -1 ) foram inferiores (P<0,01) aos demais (27 t ha -1 ano -1 ) e a produção de MS digestível (16,2 t ha -1 ano -1 ) seguiu a mesma tendência. As alterações encontradas nas variáveis estudadas foram, sobretudo, decorrentes das variações ambientais, que levaram a alterações na composição morfológica e químico-bromatológica. Em geral, maiores intervalos entre cortes proporcionaram redução na porcentagem de folhas e aumento na de hastes que, como conseqüência, levaram ao declínio nos teores de proteína bruta (PB) e na digestibilidade verdadeira in vitro da matéria seca (DVIVMS), além de aumentos nos teores de fibra em detergente neutro (FDN). A silagem de inverno promoveu discreta alteração na composição químico-bromatológica entre os tratamentos, restringindo-se a variações nos teores de PB, FDN e celulose que levaram a alterações na DVIVMS. Na silagem de verão observou-se consistência de redução do valor nutritivo com a maior extensão do intervalo entre cortes da forragem ensilada, com aumento das frações da parede celular, exceto hemicelulose, e diminuição nos componentes do conteúdo celular. Os valores de pH (4,9), apesar de elevados, estiveram dentro da amplitude de variação esperada para silagens de capins tropicais. O menor tamanho de partículas (31 mm) proporcionou maiores (P<0,01) DMV (633 kg m -3 ). Os maiores teores de MS nas silagens confeccionadas no inverno levaram a maiores perdas por gases e menores produções de efluente, com maiores taxas de recuperação de MS. A otimização do intervalo entre cortes, visando conciliar elevada produção de MS e valor nutritivo satisfatório, ocorreu ao redor dos 60 dias de crescimento vegetativo, quando a baixa digestibilidade (63,1%) foi compensada pela maior produção de MS (27 t ha -1 ano -1 ) e menores perdas (3,45% MS) no processo fermentativo. / The objectives of this study were to evaluate cutting intervals and season of the year on dry matter (DM) yield, morphological and chemical composition of Marandu grass. Treatments consisted of Marandu grass harvested at 15, 30, 45, 60, 75 and 90-d intervals and was carried out during 12 months. Part of the harvested forage was ensiled, both in the summer (January) and in the winter (July) cuts, except that of 75-d interval. In the first trial was evaluated the dry matter (DM) yield, morphological composition and nutritive value of Marandu grass. In the second trial, silage samples were submitted to chemical and physical analysis (electrical conductivity - EC, water activity - Aw, particle size - PS, fresh matter density - FMD, dry matter density - DMD, effluent yield, gases losses and dry matter recovery rate-DMRR). Randomized blocks with six treatments in the first trial and five treatments in the second one was the experimental design chosen. In the first trial data were pooled in 90-d interval to compare treatments. DM yield was lower (P<0.01) at 30 and 45-d interval (21 t ha -1 year -1 ) as compared to 15, 60, 75 and 90-d interval (27 t ha -1 year -1 ). Digestible DM yield (16.2 t ha -1 year -1 ) followed the same pattern. Values observed in the measured parameters were probably due to environmental conditions, leading to morphological and chemical composition changes. In general, samples harvested at longer cutting intervals showed a decrease in leaves, crude protein (CP) content and in vitro true DM digestibility (IVTDMD) and an increase in stems and neutral detergent fiber (NDF) content. Among treatments, the winter cut silages showed minor chemical composition changes as compared to the summer cut silages. The summer cut silages showed a trend for increasing cell wall fractions, except hemicellulose and decreasing cell soluble contents as the cutting intervals were increased. Average silage pH values were 4.9. Small particle size (31 mm) silages had higher (P<0.01) FMD (633 kg m -3 ). The higher DM content observed in the winter cut silages led to increased gases losses and DMRR and lower effluent yield. The 60-d cutting interval is recommended based on productivity (27 t ha -1 year -1 ), digestibility (63.1%) and fermentation losses (3.4% DM) values.

The aim of this thesis was to determine the effect of row spacing on sorghum yields and dry matter. The trial was established on 29 May 2015 on land belonging to the Agricultural Cooperative Milevsko, which is situated in the corn-growing area. The trial compared four varieties of sorghum, namely Aristos, Goliath, KWS Freya and KWS Sole. The varieties were sown in different row spacings, namely 75 cm, 60 cm, 45 cm a 30 cm. The samples taken on three dates were analysed for dry matter content. Each variety showed a gradual increase in the dry matter content. During the harvest on 5 October 2015 the varieties KWS Freya and KWS Sole reached an optimal value of the dry matter when planted in all spacings. All varieties produced the highest average yield of green matter when planted in rows spaced 60 cm apart. The variety Aristos produced the highest average yield of green matter. The KWS Sole variety reached the lowest average yield of green matter when planted in rows 76 cm apart. All varieties with 60 cm row spacings, except for KWS Sole, produced the highest average yield of dry matter. The highest average yield of dry matter was reached by Aristos and the lowest by KWS Sole. The results of the one-year trial did not prove a direct connection of the effect of row spacing on dry matter. The effect of row spacing on green and dry matter yield was proved. The optimum row spacing seems to be 60 cm.

Os objetivos do estudo foram avaliar os efeitos do intervalo entre cortes e da estação do ano, sobre a produção de matéria seca (MS), composição morfológica e químico-bromatológica do capim-Marandu. Os tratamentos consistiram em seis intervalos entre cortes (T15, T30, T45, T60 T75 e T90), com forragens colhidas, respectivamente, aos 15, 30, 45, 60, 75 e 90 dias de rebrotação, conduzidos ao longo de 12 meses. Parte da forragem colhida foi ensilada em janeiro (verão) e julho (inverno), exceto T75. Foram realizados dois ensaios, no primeiro houve a caracterização da produção de MS, composição morfológica e químico-bromatológica da forragem. Num segundo ensaio foi caracterizada a composição químico-bromatológica das silagens de capim-Marandu e foram avaliados alguns parâmetros físicos das mesmas, como densidade da massa verde (DMV), da massa seca (DMS), tamanho médio das partículas, condutividade elétrica (CE) e atividade de água (Aw). O processo fermentativo foi avaliado indiretamente através da quantificação das perdas por gases, produção de efluente e taxa de recuperação de MS das silagens. O delineamento experimental constituiu-se de blocos completos casualizados avaliando seis tratamentos para o primeiro ensaio e cinco no segundo. Para o ensaio de produção e qualidade da forragem os dados foram agrupados em ciclos de cortes de 90 dias para efeito de comparação entre os tratamentos. As produções de MS nos tratamentos T30 e T45 (21 t ha -1 ano -1 ) foram inferiores (P<0,01) aos demais (27 t ha -1 ano -1 ) e a produção de MS digestível (16,2 t ha -1 ano -1 ) seguiu a mesma tendência. As alterações encontradas nas variáveis estudadas foram, sobretudo, decorrentes das variações ambientais, que levaram a alterações na composição morfológica e químico-bromatológica. Em geral, maiores intervalos entre cortes proporcionaram redução na porcentagem de folhas e aumento na de hastes que, como conseqüência, levaram ao declínio nos teores de proteína bruta (PB) e na digestibilidade verdadeira in vitro da matéria seca (DVIVMS), além de aumentos nos teores de fibra em detergente neutro (FDN). A silagem de inverno promoveu discreta alteração na composição químico-bromatológica entre os tratamentos, restringindo-se a variações nos teores de PB, FDN e celulose que levaram a alterações na DVIVMS. Na silagem de verão observou-se consistência de redução do valor nutritivo com a maior extensão do intervalo entre cortes da forragem ensilada, com aumento das frações da parede celular, exceto hemicelulose, e diminuição nos componentes do conteúdo celular. Os valores de pH (4,9), apesar de elevados, estiveram dentro da amplitude de variação esperada para silagens de capins tropicais. O menor tamanho de partículas (31 mm) proporcionou maiores (P<0,01) DMV (633 kg m -3 ). Os maiores teores de MS nas silagens confeccionadas no inverno levaram a maiores perdas por gases e menores produções de efluente, com maiores taxas de recuperação de MS. A otimização do intervalo entre cortes, visando conciliar elevada produção de MS e valor nutritivo satisfatório, ocorreu ao redor dos 60 dias de crescimento vegetativo, quando a baixa digestibilidade (63,1%) foi compensada pela maior produção de MS (27 t ha -1 ano -1 ) e menores perdas (3,45% MS) no processo fermentativo. / The objectives of this study were to evaluate cutting intervals and season of the year on dry matter (DM) yield, morphological and chemical composition of Marandu grass. Treatments consisted of Marandu grass harvested at 15, 30, 45, 60, 75 and 90-d intervals and was carried out during 12 months. Part of the harvested forage was ensiled, both in the summer (January) and in the winter (July) cuts, except that of 75-d interval. In the first trial was evaluated the dry matter (DM) yield, morphological composition and nutritive value of Marandu grass. In the second trial, silage samples were submitted to chemical and physical analysis (electrical conductivity - EC, water activity - Aw, particle size - PS, fresh matter density - FMD, dry matter density - DMD, effluent yield, gases losses and dry matter recovery rate-DMRR). Randomized blocks with six treatments in the first trial and five treatments in the second one was the experimental design chosen. In the first trial data were pooled in 90-d interval to compare treatments. DM yield was lower (P<0.01) at 30 and 45-d interval (21 t ha -1 year -1 ) as compared to 15, 60, 75 and 90-d interval (27 t ha -1 year -1 ). Digestible DM yield (16.2 t ha -1 year -1 ) followed the same pattern. Values observed in the measured parameters were probably due to environmental conditions, leading to morphological and chemical composition changes. In general, samples harvested at longer cutting intervals showed a decrease in leaves, crude protein (CP) content and in vitro true DM digestibility (IVTDMD) and an increase in stems and neutral detergent fiber (NDF) content. Among treatments, the winter cut silages showed minor chemical composition changes as compared to the summer cut silages. The summer cut silages showed a trend for increasing cell wall fractions, except hemicellulose and decreasing cell soluble contents as the cutting intervals were increased. Average silage pH values were 4.9. Small particle size (31 mm) silages had higher (P<0.01) FMD (633 kg m -3 ). The higher DM content observed in the winter cut silages led to increased gases losses and DMRR and lower effluent yield. The 60-d cutting interval is recommended based on productivity (27 t ha -1 year -1 ), digestibility (63.1%) and fermentation losses (3.4% DM) values.

Fodder maize cultivation under low mountain conditions in Central Europe presents obstacles for organic dairy farmers; low temperatures and high precipitation values in spring delay the juvenile development of maize, which leads to lower and fluctuating yields. Increasing the soil temperature during the critical growth phase of maize in spring is beneficial for maize cultivation. For this reason, 0.15 m high ridge-row cultivation (RCM) of maize was compared to a typical flat surface cultivation method (FCM) with 0.75 m row spacing in three environments (En) in 2017, 2018 and 2020 on-farm at low mountain sites in Germany. In the experiment, with randomised block design and one-factorial arrangement, soil temperature (ST) at 0.05 m soil depth at midday, field emergence (FE) 4, 8, 16 and 20 days after sowing (DAS), dry matter yields (DM) in every En and plant development and N, P, K content in En 2020 were investigated. RCM led to a significantly higher ST 4 DAS in every En, 12 and 20 days in 2018 and 8 and 16 DAS in 2020. RCM did not accelerate maize FE but positively impacted plant development and starch content. RCM generated a higher dry matter (DM) yield of whole maize plants and corn cobs, and a higher protein yield than FCM. RCM slightly increased the plant-available P and Mg content from 0 to 0.3 m and influenced significantly the mineral N content from 0 to 0.3 m at the beginning of grain development. RCM, a simple cultivation technique, demonstrated benefits for maize cultivation, particularly for climatically marginal locations in Germany.