Effects of nitrogen, phosphorus and vermicompost fertilizers on productivity of groundnut (Arachis hypogaea L.) in Babile, Eastern Ethiopia

G. Bekele¹*, N. Dechassa², T. Tana² and J.J. Sharma²

¹Depatment of Plant Sciences Bedele College of Agriculture and Forestry, Mettu University, P.O.Box 138, Ethiopia
²School of Plant Sciences, College of Agriculture and Environmental Sciences, Haramaya University, P.O.Box 138, Ethiopia
*Corresponding author: getme.bekele@gmail.com

Abstract:

Though groundnut (Arachis hypogaea L.) is a main cash crop for smallholder farmers in several districts of eastern Ethiopia, its yield is very low. Farmers apply little or no fertilizers to grow the crop possibly because no generic or recommended fertilizers rates available for farmers. Therefore field experiments were conducted for two consecutive cropping seasons in Babile district, to prove the hypothesis that one of the major factors that severely reduce the yield of the crop was lack of nutrients in the soil with the objective of investigating the effects of applying mineral NP fertilizers and vermicompost on the productivity of improved groundnut variety ‘BaHa-Gudo’. The experiment was 3 × 3 × 3 factorial with three replications laid down in a randomized complete block design comprising nitrogen (0, 23 and 46 kg N ha^-1), phosphorus (0, 46 and 92 kg P₂O₅ ha^-1) and vermicompost (0, 2.5 and 5 t vermicompost ha^-1). The data on crop growth, nodulation and yield were collected and subjected to analysis of SAS 9.2 software. Means separation were made using Duncans Multiple Range Test (DMRT) at 5% level of significance. The results revealed that growth, yield attributes, and yields were significantly (P < 0.01) affected by the main and interactions effect of the treatments. The pod yield obtained from combined application of 46: 46 kg N: P₂O₅ ha^-1 and 2.5 t vermicompost ha^-1 exceeded the pod yield produced from nil application of fertilizers by about 100%. The economic analysis also indicated that the highest marginal rate of return (671%) and net benefit ($ 1,830) ha^-1 were obtained from combined application of 46: 46 kg N: P₂O₅ ha^-1 and 2.5 t vermicompost ha^-1. From the results it could be concluded that applying the aforementioned doses of fertilizers combination would enable farmers increase productivity of groundnut so as to enhance farmers’ income and livelihoods.

Key words:

combined application, Groundnut;, mineral NP fertilizers, Vermicompost

Fatty acid composition of oilseed rapeseed genotypes as affected by vermicompost application and different thermal regimes

E. Samadzadeh Ghale Joughi¹, E. Majidi Hervan¹*, A.H. Shirani Rad² and GH. Noormohamadi¹

¹Department of Agronomy, Science and Research Branch, Islamic Azad University, Tehran, Iran
²Department of Agronomy, Seed and Plant Improvement Institute, AREEO, Karaj, Iran
*Correspondence: majidi_e@yahoo.com

Abstract:

Vegetable oils with a high relative amount of unsaturated fatty acids are of great significance for human health. Hence, in a 2-year factorial split plot experiment, the effects of different sowing date (optimum (October 17) and late (October 27)), vermicompost (0 and 20 ton ha^-1) and genotypes (BAL104, DIE710.08, BAL102, FJL330, FJL290 and Okapi) on the fatty acid composition of rapeseed were evaluated. Rapeseed genotypes and the combination of sowing date and vermicompost application were randomized to sub and main-plots, respectively. The present results revealed that yield, oil percentage and fatty acids composition is affected by sowing dates along with genotypes. However, the unsaturated fatty acid, eicosanoic acid was not affected by interaction sowing date and genotype. Vermicomposting increased the yield, oil percentage, oleic, linoleic and linolenic acids and decrease erucic unsaturated fatty acid. The FJL290 and BAL102 genotypes produced the highest values of grain yield (5,853 and 5,763 kg ha⁻¹, respectively), oil percentage (43.98% and 43.85%, respectively), linoleic % acid (20.51 and 20.37% respectively), oleic % acid (65.23 and 64.93% respectively) and linolenic % acid (7.20 and 7.09% respectively) in comparison to the other genotypes, when they were sown at the optimum sowing date. The FJL290 and BAL102 also accelerated their growth period at the late sowing date. Consequently, oleic, linoleic and linolenic acids had the highest direct and indirect effect influence on grain oil percentage indicating their importance as selection criteria to improve yield and oil quality of rapeseed. Concluding the combination of sowing date, vermicompost and FJL290 and BAL102 lines may be the most favourable cropping strategy for rapeseed production in Iran.

Key words: