Response of Groundnut (Arachis hypogaea L.) Genotypes to Combined Application of Phosphorus and Foliar Zinc Fertilizers in Central Tigray, Ethiopia

Background Adequate phosphorus (P) and foliar zinc (Zn) in groundnut required for obtaining Zn-enriched grain and optimum yield. However, it was very low in the area. Due to that objective of the study was to investigate the response of groundnut genotypes to combined application of phosphorus and zinc on yield and nutritional contents. A field experiment was conducted at Sheka-Tekli in 2017/18 cropping season. Methods The treatments were consisted of three groundnut genotypes (ICGV00308, ICGV91114 and Sedi) as main plot and four combined PZn fertilizer levels (00), 10 kg P/ha + 0.50 g Zn/L, 20 kg P/ha + 1 g Zn/L and 30 kg P/ha + 1.5 g Zn/L as sub plot were assigned in split plot design with tree replications. Result The result indicated that yield and yield components respond significantly to the main and interaction effects. The highest significant seed yield (2529 kg/ha) and protein content (37.79%) were obtained in response to the application of P30Zn1.5 fertilizer on sedi variety in the loamy sand soil. The percentage of crude protein and fat content had significantly affected by interaction components. Most of the yield component traits showed strong positive correlation with seed yield. While the lowest seed yield was recorded from ICGV00308 without fertilizer. The highest fat content (43.95%) was gained from genotype ICGV00308 at P30Zn1.5 fertilizer. From the interaction of sedi with P30Zn1.5 fertilizer was recorded highest protein content. Based on economic analysis the highest MRR (380.58%) was obtained from ICGV00308 genotype at P10Zn0.5 fertilizer. Conclusion From the result of the study, application of PZn fertilizer increases seed yield of groundnut. Therefore, based on the MRR result ICGV00308 genotype at P10Zn0.5 fertilizer was optimum for groundnut production in the study area and similar agro-ecologies.