The effects of nitrogen and phosphorus on yield and yield components of garlic (Allium sativum L) varities at Beressa watershed, Mesqan Woreda, South CentralEthiopia

Abstract

Garlic (Allium sativum L.) is one of the most important bulb vegetables used as spice and flavoring agent of food and medicinal plants throughout the globe. It is a cold weather crop with high water and nutrient requirement. Numerous problems accounted for the low productivity of garlic in Ethiopia, among which appropriate fertilizer management is the major issue. Therefore, a field experiment was conducted with the objectives to investigate the effect of nitrogen and phosphorus levels on yield and yield attributes of two garlic varieties at Beressa watershed, Mesqan woreda, south –central Ethiopia under supplemental irrigation from November to April 2010/11. The treatments consisted of 2 garlic varieties Local and improved, 4 levels of N (0, 50, 100 and 150 kg N/ha) and 3 levels of P (0, 50 and 100 kg P2O5/ha) triplicated in a factorial randomized block design. Data on yield and yield components were collected. Varieties differed significantly on bulb diameter, mean clove fresh weight, bulb fresh and dry weight and bulb yield. Nitrogen application significantly influenced bulb yield and yield component. Phosphorus had significantly influenced bulb diameter, bulb fresh and dry weight, mean clove fresh weight and bulb yield and also yield all the yield attributes were significantly affected by the interaction of N and P. However; the three way interaction effect between N, P and variety were found to be significant for the bulb dry matter at 120 DAE and total bulb yield. The highest bulb yield of 3.34 t/ha was achieved at 100 kg N + 100 kg P2O5/ha combination, and was 244 % higher than the control and statistically similar to the yield of 3.27 t/ha obtained from 100 kg N and 50 kg/ha P2O5 application for Tsedey92. Hence, based on the economics of fertilizers to the mean bulb yield for the experiment, application of 100 kg N and 50 kg P2O5 /ha to variety Tsedey92 had tentatively recommended for the study area.