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Browsing by Author "Prasad, P. V. Vara"

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    Conservation agricultural practices in West Africa
    Prasad, P. V. Vara; Naab, Jesse B.; Doumbia, M. D.; Dalton, T. D. (Blacksburg, VA: SANREM CRSP, 2011)
    The poster provides an overview of the research conducted by the SANREM CRSP's Long-Term Research Activity 8. This research team hopes to assess conservation agriculture practices and identify practices suitable to the conditions present in the West African region in order to facilitate an increase in productivity and economic returns to smallholder farmers with rainfed agricultural operations.
  • Conservation agricultural practices in West Africa: Challenges and opportunities
    Prasad, P. V. Vara; Naab, Jesse B.; Doumbia, M. D.; Dalton, T. D. (2011)
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    Conservation Agriculture Improves Soil Quality, Crop Yield, and Incomes of Smallholder Farmers in North Western Ghana
    Naab, Jesse B.; Mahama, George Y.; Yahaya, Iddrisu; Prasad, P. V. Vara (Frontiers Media, 2017-06-21)
    Conservation agriculture (CA) practices are being widely promoted in many areas in sub-Saharan Africa to recuperate degraded soils and improve ecosystem services. This study examined the effects of three tillage practices [conventional moldboard plowing (CT), hand hoeing (MT) and no-tillage (NT)], and three cropping systems (continuous maize, soybean–maize annual rotation, and soybean/maize intercropping) on soil quality, crop productivity, and profitability in researcher and farmer managed on-farm trials from 2010 to 2013 in northwestern Ghana. In the researcher managed mother trial, the CA practices of NT, residue retention and crop rotation/intercropping maintained higher soil organic carbon, and total soil N compared to conventional tillage practices after 4 years. Soil bulk density was higher under NT than under CT soils in the researcher managed mother trails or farmers managed baby trials after 4 years. In the researcher managed mother trial, there was no significant difference between tillage systems or cropping systems in maize or soybean yields in the first three seasons. In the fourth season, crop rotation had the greatest impact on maize yields with CT maize following soybean increasing yields by 41 and 49% compared to MT and NT maize, respectively. In the farmers’ managed trials, maize yield ranged from 520 to 2700 kg ha-1 and 300 to 2000 kg ha-1 for CT and NT, respectively, reflecting differences in experience of farmers with NT. Averaged across farmers, CT cropping systems increased maize and soybean yield ranging from 23 to 39% compared with NT cropping systems. Partial budget analysis showed that the cost of producing maize or soybean is 20–29% cheaper with NT systems and gives higher returns to labor compared to CT practice. Benefit-to-cost ratios also show that NT cropping systems are more profitable than CT systems. We conclude that with time, implementation of CA practices involving NT, crop rotation, intercropping of maize and soybean along with crop residue retention presents a win–win scenario due to improved crop yield, increased economic return, and trends of increasing soil fertility. The biggest challenge, however, remains with producing enough biomass and retaining same on the field.
  • Effect of contrasting sources of organic and inorganic fertilizers on growth and yield maize in dry agro-ecology in Northern Ghana
    Kanton, R. L.; Ahiabor, B. D. K.; Ansoba, E.; Asungre, A. P.; Lamini, S.; Mahama, George Y.; Prasad, P. V. Vara (2013)
    Declining maize yields due to a myriad of factors such as inherently poor soils, continuous cropping of cereal after cereal, high cost and unavailability of chemical fertilizers, continuous crop residue removal and soil erosion and run-off have all had their toll low soil fertility and reduced maize yields in northern Ghana. To address this negative trend a field trial was conducted at the Manga Agricultural Research Station in the Upper East Region of Ghana, which represents a Sudan Savanna agro-ecology in the country. The experiment was established as a complete block design with 4 replications with plot dimension of 4.5 m x 5 m. The experimental treatments comprised available sources of both organic and chemical fertilizers currently being used by peasant farmers in Ghana. The experimental factors studied were nitrogen fertilizer rates: 0 kg N/ha; 40 kg N/ha and 80 kg N/ha; length of tied ridges were: 2 m and 4 m wide and crop residue management practices were: total crop residue removal; 50% crop residue removal; 100% crop residue retention and 50% crop residue retention. The trial was established as a randomized complete block design with 4 replications. The results of this study revealed that the chemical fertilizers with micro nutrients such as S, Zn and Mg produced taller plants with superior stem dimensions and also produced tassels and silk significantly earlier than their counterparts. They also produced the best grain and straw yields, due to higher cob numbers, bolder grain and higher harvest indices. Poultry manure and sheep manure were the best amongst the organic sources evaluated.
  • Effects of double cropped on yield and biomass accumulation of cover crops in Kansas
    Roozeboom, K.; Mahama, George Y.; Mengel, D. B.; Prasad, P. V. Vara (2013)
    The contribution of nitrogen (N) by cover crops is an important component of sustainable agriculture and alternative source of N. Legume summer and winter cover crops can decrease inorganic N fertilizer requirements and production costs through symbiotic N2 fixation. It is also vital to make maximum use of the available land during the growing season. However, summer crop yields may be decreased due to shortened length of growing season and risk of water shortage. The objectives of this research were to (a) to evaluate the performance of doubled cropped soybean and grain sorghum yield following winter wheat, and (b) to determine total biomass production, N and carbon accumulation of various cover crops following winter wheat. Field experiments were conducted at two locations (Ashland Bottoms and North Farm both in Riley County, Kansas) in 2012. The experimental design was a randomized complete block design with four replications. Five crops, cowpea [Vigna unguiculata (L.) Walp], sunn hemp (Crotolaria juncea), pigeon pea [Cajanus cajan (L.) Millsp], soybean [Glycine max (L.) Merr.], and grain sorghum [Sorghum bicolor (L.) Moench] were randomly assigned to the experimental units. Nitrogen and carbon concentrations in the above ground parts were determined. There was a significant interaction between location and crop (P
  • Effects of nitrogen fertilizer on growth and yield of maize varieties with different maturities in a dry agro-ecology of Northern Ghana
    Larbi, A.; Kanton, R. L.; Buah, S.; Kombiok, J. M.; Ansoba, E.; Asungre, A. P.; Lamini, S.; Prasad, P. V. Vara (2013)
    Declining maize yields due to a myriad of factors such as inherently poor soils, continuous cropping of cereal after cereal, high cost and unavailability of chemical fertilizers have all contributed to the above phenomenon. To address this negative trend a field trial was conducted at the Manga Agricultural Research Station in the Upper East Region of Ghana, which represents a Sudan Savanna agro-ecology in the country. The trial was established as a randomized complete block design with 4 replications. The plot dimensions are 4.5 m x 5 m, and maize was sown on ridges made by bullocks. All cultural practices are as recommended for maize production in Ghana. For the extra-early maize, the, however, there were significant differences among the rates of N applied, with application of N at the rate of 120 kg ha-1 recording the highest grain yield. For the early maturity group there were significant (P (MARR) (150%). This means that these treatments 40N and 80N could be recommended for uptake by farmers or for further research work.
  • Effects of soil and water management practices on crop productivity in West Africa
    Naab, Jesse B.; Prasad, P. V. Vara; Doumbia, M. D.; Seyni, S.; Traore, H.; Barro, A. (2012)
    Several soil and water managment practices were tested under on-station and on-farm conditions in four different countries in West Africa (Ghana, Burkina Faso, Niger and Mali). Some of the soil and water management practices include - minimum tillage, contour ridging, tied ridging, use of stone ridges and grass bunds, application of microdose fertilizer along with compost, application of phosphorus fertilizer, intercropping systems and crop rotations to minimize soil erosion, harvest rainwater and increase soil fertility and crop productivity. Our results showed that use of these practices significanly increased productivity of several crops such as sorghum, millet, maize, peanut, cowpea and soybean. Grain yield of cereal and legume crops were similar under minimum tillage and conventional tillage practices in northern Ghana. Use of contour ridging increased sorghum grain yield by >25% in Mali. Tied ridges increase grain yield of sorghum and millet by >100% in Niger. Use of stone rows and grass stripes increased grain yield of improved sorghum genotypes by >20% in Burkina Faso. Use of mechanized zai and compost increased millet yield by >50% in Burkina Faso. Application of phosphorus fertilizer increased grain yield of sorghum, millet, and soybean in Niger and Ghana. Use of conservation practices such as minimum tillage, cereal-legume crop rotations and intercropping systems showed yield benefits from 5 to 30% in Ghana and Mali. Overall, these result suggest that there are opportunities to improve productivity of cereal and legume crops in West Africa through using sustainable intensive soil, water and crop management practices.
  • Genotypic differences in yield and nitrogen use efficiency of sorghum
    Prasad, P. V. Vara; Mahama, George Y.; Mengel, D. B.; Tesso, T. T. (2012)
    Grain sorghum is an important crop in the semi-arid regions of Africa, Asia and United States. Productivity of grain sorghum is limited by soil fertility, especially nitrogen (N). Sorghum genotypes are known to vary in their response to nitrogen, however, the information on nitrogen use efficiency is limited. The objectives of this research were to (a) determine the response of sorghum genotypes (hybrids and inbred lines) to nitrogen fertilizer; and (b) quantify genotypic differences in nitrogen use efficiency (NUE). Field experiments were conducted at three locations (Hays, Ottawa and Manhattan in; Kansas) in 2010 and 2011. Six hybrids and six inbred lines of grain sorghum were grown with 0N, 45N and 90 kg N ha-1. The experimental design was a split-plot design with nitrogen regimes as main plots and genotypes as sub-plot, with four replications. Planting was done in May and June across all the locations, and nitrogen fertilizer (Urea, 46% N) was applied at emergence. Nitrogen concentrations in the grain and component of NUE were determined for Ottawa and Manhattan. There were significant effects of genotypes (P
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    Improving crop productivity of smallholder farmers through conservation agricultural practices; key findings from Ghana and Mali
    Prasad, P. V. Vara; Naab, Jesse B.; Kanton, R. L.; Doumbia, M. (2014)
    This PowerPoint summarizes the research and training activities of SANREM’s regional project in Ghana and Mali. The top six findings from each country are reported and described with detailed data. These research results discuss tied ridges, minimal tillage, fertilizer application, crop rotations, phosphorous nutrition, gentoypes, contour ridging and crop residues.
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    Improving soil quality and crop productivity through conservation agricultural practices in cropping systems of West Africa
    Prasad, P. V. Vara; Dalton, T. (Blacksburg, VA: SANREM CRSP, OIRED, Virginia Tech, 2010)
    This presentation describes conservation agriculture research activities in West Africa, with a focus on Ghana and Mali (LTRA-8). The variation between the two countries and their differing research focus creates a number of opportunities to further the study of conservation agriculture. For example, in both countries alternative uses for crop residues is raised as a major concern for conservation agriculture adoption. In Ghana, crop residues are gathered and sold after the harvest while in Mali, free ranging livestock survive by grazing upon field residues. As a result of such problems, the proposal emphasizes that innovation for conservation agriculture must be a farmer led activity.
  • Improving soil quality and crop productivity through conservation agriculture in Mali, West Africa
    Kone, M.; Doumbia, Mamadou D.; Traoré, S. H.; Samake, O.; Prasad, P. V. Vara; Dalton, Timothy J.; Naab, Jesse B. (2012)
    Declines in crop yields (21% for sorghum and millet) and soil fertility (29% for C) have made conservation (CA) a significant management option for selected cropping systems of Mali. Baseline assessments and rapid rural appraisals have indicated that the classical CA components need to be modified, not only to remove permanent soil cover, but also to include capturing rainwater. The improved conservation agriculture production systems (CAPS) account for 40 to 70% running off rainwater and feeding cover crops and crop residues to cattle, which is a key component of local production systems.
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    Influence of conservation agricultural practices on maize and soybean yield in Upper West region of Ghana
    Naab, Jesse B.; Prasad, P. V. Vara (Blacksburg, VA: SANREM CRSP, 2011)
    Sustainable intensification of conservation agricultural practices can improve crop productivity and soil health. These practices will help farmers to adapt their crop production systems to future changing climates and minimize carbon and water foot print. Objectives of this research were to evaluate influence of tillage practices (conventional, minimum tillage and no tillage), fertilizer management, and soil and water harvesting techniques on grain yield of maize and soybean in different cropping systems under on-farm conditions in upper west region of Ghana. (Author's Abstract)
  • Influence of nitrogen fertilizer on growth and yield of grain sorghum hybrids and inbred lines
    Mahama, George Y.; Prasad, P. V. Vara; Mengel, D. B.; Tesso, T. T. (2014)
    Grain sorghum [Sorghum bicolor (L.) Moench] is an important crop in semiarid regions of the world because of its drought tolerance. Nitrogen is one of the most limiting nutrients in crop production due to low availability and loss. We hypothesize that there are differences in physiological and yield traits among grain sorghum genotypes in response to N. The objectives of this study were to determine the responses of sorghum genotypes (hybrids and inbred lines) to N fertilizer and the relationship between their physiological and yield traits. Field experiments were conducted at two locations in Kansas for two seasons (2010 and 2011). Genotype × N regimes and year × genotype interactions were significant for leaf chlorophyll, aboveground biomass, grain yield, and seed number. Overall, the hybrids were superior to inbred lines for grain yield and total aboveground biomass, but grain yields of inbred lines TX2783 and TX7000 were comparable to hybrids. Maximum total aboveground biomass, leaf chlorophyll index, and grain yield were obtained at 90 kg N ha–1. Across years, application of 45 and 90 kg N ha–1 resulted in an increase in yield of 13 and 48% over 0 kg N ha–1, respectively. No strong relationship was detected between genotypes and leaf chlorophyll index or chlorophyll a fluorescence and grain yield, but there was a strong relationship between seed number and total aboveground biomass and grain yield. Leaf chlorophyll index and chlorophyll a fluorescence did not provide physiological basis for differences in N response among the genotypes for grain yield.
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    Knowledge of households, cropping systems, perceptions on conservation agricultural practices in Upper West region of Ghana
    Yahaya, Iddrisu; Hashim, Ibrahim; Naab, Jesse B.; Prasad, P. V. Vara; Dalton, Timothy J. (Blacksburg, VA: SANREM CRSP, 2011)
    This poster describes the recent findings of the SANREM CRSP's Long-Term Research Activity 8 in the Upper West region of Ghana. This research team interviewed 358 farmers in 12 communities of 3 districts in Ghana in order to collect baseline socioeconomic data as well as to estimate farmer knowledge and perceptions regarding conservation agriculture. In addition to revealing crop productivity and marketing data, research results indicated that farmers were aware of the importance of soil conservation and expressed interest in learning more about conservation agriculture practices and integrated pest management.
  • Nitrogen use efficiency in grain sorghum genotypes
    Prasad, P. V. Vara; Mahama, George Y.; Mengel, D. B.; Staggenborg, Scott A.; Tesso, T. T. (2011)
    Grain sorghum is an important crop in the semi-arid regions. Productivity of grain sorghum is limited by soil fertility, especially nitrogen (N). Sorghum genotypes are known to vary in their response to nitrogen, however, the information on N use efficiency (NUE) is limited. Objectives of this research were to (a) determine the response of sorghum genotypes (hybrids and inbred lines) to N; and (b) quantify genotypic differences in nitrogen use efficiency. Field experiments were conducted at three locations (Hays, Ottawa and Manhattan, Kansas) in 2010. Six hybrids and six inbred lines were grown at three N regimes; 0, 45 and 90 kg N ha-1. Experimental design was a split-plot design with N as main plots and genotypes as sub-plots, with four replications. Planting was done in May and June across all the locations, and N fertilizer (Urea, 46%N) was applied at emergence. Data on biomass was measured at vegetative, flowering and maturity, and grain yield at maturity. Concentrations of N in the grain and components of NUE were determined for Ottawa. There were significant effects (P
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    Opportunities for sustainable intensification of agricultural practices to improve crop productivity of small holding farmers in West Africa
    Prasad, P. V. Vara; Naab, Jesse B.; Doumbia, Mamadou; Dalton, Timothy (Blacksburg, VA: SANREM CRSP, 2011)
    This presentation provides an overview of the research efforts of the SANREM CRSP's Long-Term Research Activity 8: Improving soil quality and crop productivity through CAPS in West Africa. It outlines the present production constraints on agriculture in West Africa, the potential role of Conservation Agriculture practices, and the research and results of the current program incorporating Conservation Agriculture practices in order to augment economic returns and productivity to rain-fed smallholders while improving soil quality and natural resource use efficiency.