Influence of Alectra vogelii inoculation and phosphorus fertilizer application on phenology, yield components and grain yield of bambara groundnut genotypes

Abstract

In sub-Saharan Africa, the parasitic Alectra vogelii is seriously threatening Bambara groundnuts, farmers to suffer yield losses of up to 100 %. The objective of this study was to determine the effects of phosphorus (P) application and Alectra vogelii inoculation on Bambara groundnut genotypes for growth and reproductive phrase. The experiment was conducted in 2020 at the Henderson Research Station in Mazowe, Zimbabwe in a 2 × 2 × 26 factorial design with 26 genotypes arranged in a completely randomized design (CRD) with four replications, two P rates (0 and 20 kg ha-1) and two levels of inoculation (with and without Alectra vogelii). Half of the perforated black plastic bags were inoculated with Alectra vogelii seeds. The results showed a significant (p < 0.001) interaction between P application and Alectra vogelii inoculation, leading to decreased Alectra vogelii counts after 109 days, days to maturity, days to flowering, and chlorophyll content. There was a significant (p < 0.001) interaction between Bambara groundnut genotypes and Alectra-inoculation on number of pods, pod weight, number of seeds, and grain yield. Alectra vogelii parasitism significantly (p < 0.001) decreased number of pods, pod weight, number of seeds, and grain yield across all groundnut genotypes. G2, G23, G24, and G25 genotypes exhibited tolerance to Alectra vogelii, with grain yield per plant of 4.82, 6.12, 5.65, and 5.34 g, respectively, outperforming other genotypes. It was found that the combination of 20 kg P ha−1 with Alectra-resistant genotypes improved Bambara groundnut productivity.

Keywords

• Parasitic weed
• Resistant
• Stimulation
• Tolerant
• Yellow witchweed