Odhiambo, J. J. O.Lusiba, S. G.Mashele, Ntombifuthi Shane2026-06-182026-06-182026-05-19Mashele, N.S. 2026. Effects of bio-fertilizer and phosphorus application on growth, yield, yield components, and phosphorus nutrition of cowpeas grown in two different soil types. . .https://univendspace.univen.ac.za/handle/11602/3220M.Sc. in Agriculture (Soil Science)Department of Plant and Soil SciencesCowpea (Vigna unguiculata L. Walp) is a leguminous crop that is native to Africa. This crop is cultivated for food, animal feed, and organic manure. Cowpea also contributes nitrogen (N) to the soil through the process of biological nitrogen fixation. Among other quality properties, cowpea leaves and grain contain essential nutrient elements and protein. The production of cowpeas, however, faces obstacles that reduce their productivity. This is despite the significant benefits cowpeas provide to people, animals, and soils. Cowpea productivity is limited by the lack of essential nutrient elements in croplands, particularly phosphorus (P). One way by which we could address low P in croplands is the addition of P-fertilizers. However, because cowpea crop is primarily grown by unemployed small-holder farmers and that P fertilizer is scarce, expensive, and inefficient, its ability to exhibit high growth and yield is limited by low P levels in soils. Alternatively, the availability of P in soils could be improved by adding phosphate solubilizing bacteria and inoculating with rhizobial inoculants. This study investigated the effects of rhizobial inoculants, P fertilizer, and phosphate-solubilizing bacteria addition on growth and yield-related parameters of cowpeas cultivated in soils with varying characteristics. Field experiments were conducted at the Agriculture Research Council - Tropical and Subtropical Crops (ARC-TSC) and the Sabie River area during the 2019/20 and 2020/21 summer seasons. ARC-TSC and Sabie River sites have different soil types. That is, the former has Hutton soils (sandy soil) while the latter has Glenrosa (loam-sandy soil) soil type. The field study was conducted using a 2 x 5 factorial experiment layout in a Randomised Complete Block Design (RCBD) replicated three times. The experimental design was done in two locations, namely Sabie River (Glenrosa soil type) and ARC (Hutton soil type). The said designs had five treatments, and these were Control (C) - no fertilizer, P, Bradyrhizobium + Phosphorus (BR + P), Bio-fertilizer + Phosphorus (BIO + P), and Bradyrhizobium + Bio-fertilizer + P (BR + P +BIO). The experiment was conducted under rain-fed conditions. During the flowering growth stage, biomass, including shoot, root, number of root nodules, and weight were determined. At harvest stage, shoot biomass, number of pods/plant, grain yield, shoot and grain P uptake, and available P in the rhizosphere were determined. Data were subjected to a normality test and analysed using a Genstat software, 24th edition program. Where significant differences within the treatments were observed, a comparison of mean was made using the least significant difference (LSD) method at a 5% significance interval. Both the soil type and treatment had significant (p ≤ 0.01) effect on all measured cowpea parameters during the 2019/2020 and 2020/21 planting seasons. Hutton soil at the ARC site produced significantly higher shoot and root dry matter, number and weight of nodules, number of pods, and grain yield than Glenrosa soil at Sabie River site. Results show that the addition of Phosphate solubilizing bacteria + Bradyrhizobium + Superphosphate significantly improved shoot dry matter, root dry matter, number of nodules, nodule dry weight, number of pods, and grain yield of cowpea relative to the control. However, BR+P+BIO significantly differed from BR+P and BIO+P in terms of the shoot dry and root dry matters, number of nodules, nodule dry weight, number of pods, and grain yield of cowpea in both soil types. Compared to the other treatments, BR+P+BIO application enhanced P nutrition of shoots and grains, and available P in rhizosphere soil. Study findings suggest that using bio-fertilizer and P application could be a viable strategy to improve crop yield and P nutrition in cowpea cultivation. Further research and field trials, however, might be necessary to optimize application rates and assess long-term effects on soil fertility, crop performance, and the importance of considering soil types in agricultural practices. These findings contribute valuable insights for sustainable agricultural practices to enhance cowpea production and ensure food security. This has implications for sustainable agricultural practices that enhance crop yields and nutrient use efficiency in cowpea production.1 online resource (xi, 63 leaves): color illustrationsenUniversity of VendaCowpeaUCTDBio-fertilizerPhosphorusSoil typeYield-related parametersPhosphorus nutritionDissertationMashele NS. Effects of bio-fertilizer and phosphorus application on growth, yield, yield components, and phosphorus nutrition of cowpeas grown in two different soil types. []. , 2026 [cited yyyy month dd]. Available from:Mashele, N. S. (2026). <i>Effects of bio-fertilizer and phosphorus application on growth, yield, yield components, and phosphorus nutrition of cowpeas grown in two different soil types</i>. (). . Retrieved fromMashele, Ntombifuthi Shane. <i>"Effects of bio-fertilizer and phosphorus application on growth, yield, yield components, and phosphorus nutrition of cowpeas grown in two different soil types."</i> ., , 2026.TY - Dissertation AU - Mashele, Ntombifuthi Shane AB - Cowpea (Vigna unguiculata L. Walp) is a leguminous crop that is native to Africa. This crop is cultivated for food, animal feed, and organic manure. Cowpea also contributes nitrogen (N) to the soil through the process of biological nitrogen fixation. Among other quality properties, cowpea leaves and grain contain essential nutrient elements and protein. The production of cowpeas, however, faces obstacles that reduce their productivity. This is despite the significant benefits cowpeas provide to people, animals, and soils. Cowpea productivity is limited by the lack of essential nutrient elements in croplands, particularly phosphorus (P). One way by which we could address low P in croplands is the addition of P-fertilizers. However, because cowpea crop is primarily grown by unemployed small-holder farmers and that P fertilizer is scarce, expensive, and inefficient, its ability to exhibit high growth and yield is limited by low P levels in soils. Alternatively, the availability of P in soils could be improved by adding phosphate solubilizing bacteria and inoculating with rhizobial inoculants. This study investigated the effects of rhizobial inoculants, P fertilizer, and phosphate-solubilizing bacteria addition on growth and yield-related parameters of cowpeas cultivated in soils with varying characteristics. Field experiments were conducted at the Agriculture Research Council - Tropical and Subtropical Crops (ARC-TSC) and the Sabie River area during the 2019/20 and 2020/21 summer seasons. ARC-TSC and Sabie River sites have different soil types. That is, the former has Hutton soils (sandy soil) while the latter has Glenrosa (loam-sandy soil) soil type. The field study was conducted using a 2 x 5 factorial experiment layout in a Randomised Complete Block Design (RCBD) replicated three times. The experimental design was done in two locations, namely Sabie River (Glenrosa soil type) and ARC (Hutton soil type). The said designs had five treatments, and these were Control (C) - no fertilizer, P, Bradyrhizobium + Phosphorus (BR + P), Bio-fertilizer + Phosphorus (BIO + P), and Bradyrhizobium + Bio-fertilizer + P (BR + P +BIO). The experiment was conducted under rain-fed conditions. During the flowering growth stage, biomass, including shoot, root, number of root nodules, and weight were determined. At harvest stage, shoot biomass, number of pods/plant, grain yield, shoot and grain P uptake, and available P in the rhizosphere were determined. Data were subjected to a normality test and analysed using a Genstat software, 24th edition program. Where significant differences within the treatments were observed, a comparison of mean was made using the least significant difference (LSD) method at a 5% significance interval. Both the soil type and treatment had significant (p ≤ 0.01) effect on all measured cowpea parameters during the 2019/2020 and 2020/21 planting seasons. Hutton soil at the ARC site produced significantly higher shoot and root dry matter, number and weight of nodules, number of pods, and grain yield than Glenrosa soil at Sabie River site. Results show that the addition of Phosphate solubilizing bacteria + Bradyrhizobium + Superphosphate significantly improved shoot dry matter, root dry matter, number of nodules, nodule dry weight, number of pods, and grain yield of cowpea relative to the control. However, BR+P+BIO significantly differed from BR+P and BIO+P in terms of the shoot dry and root dry matters, number of nodules, nodule dry weight, number of pods, and grain yield of cowpea in both soil types. Compared to the other treatments, BR+P+BIO application enhanced P nutrition of shoots and grains, and available P in rhizosphere soil. Study findings suggest that using bio-fertilizer and P application could be a viable strategy to improve crop yield and P nutrition in cowpea cultivation. Further research and field trials, however, might be necessary to optimize application rates and assess long-term effects on soil fertility, crop performance, and the importance of considering soil types in agricultural practices. These findings contribute valuable insights for sustainable agricultural practices to enhance cowpea production and ensure food security. This has implications for sustainable agricultural practices that enhance crop yields and nutrient use efficiency in cowpea production. DA - 2026-05-19 DB - ResearchSpace DP - Univen KW - Cowpea KW - Bio-fertilizer KW - Phosphorus KW - Soil type KW - Yield-related parameters KW - Phosphorus nutrition LK - https://univendspace.univen.ac.za PY - 2026 T1 - Effects of bio-fertilizer and phosphorus application on growth, yield, yield components, and phosphorus nutrition of cowpeas grown in two different soil types TI - Effects of bio-fertilizer and phosphorus application on growth, yield, yield components, and phosphorus nutrition of cowpeas grown in two different soil types UR - ER -