Abstract

Abreham Mulatu, Bizuayehu Tesfaye and Essubalew Getachew

Garlic is one of the most important bulb vegetables used as spice and flavoring agent of food and medicinal plants throughout the globe. Numerous problems accounted for the low productivity of garlic in Ethiopia, among which appropriate fertilizer management is the major factor. Therefore, this experiment was undertaken with the objective to investigate the effect of nitrogen and phosphorus levels on growth and bulb yield of two garlic varieties at Beressa watershed, Mesqan woreda, South Central Ethiopia under supplemental irrigation from November to April 2010/11. The treatments for the experiment were two garlic varieties, 4 levels of Nitrogen (0, 50, 100 and 150 kg N/ha) and 3 levels of Phosphorus (0, 50 and 100 kg P2O5/ha) arranged in Randomized Complete Block Design. Data on growth parameters (days to maturity, plant height, leaf number, leaf area, leaf area index and shoot dry weight) and total bulb yield were collected. The varieties showed significant difference on plant height, leaf area, leaf area index, shoot dry weight and bulb yield. Nitrogen also significantly affected bulb yield along with all the growth parameters. Phosphorus had significantly influenced number of leaf per plant and bulb yield. Leaf number per plant and bulb yield was significantly affected by the interaction of N and P. The highest bulb yield of 3.34 t/ha was recorded at 100 kg N + 100 kg P2O5/ha combination, and that was 244 % higher than the control and statistically similar to the yield 3.27 t/ha obtained at 100 kg N and 50 kgP2O5/ha combination for Tsedey92. Hence, tentatively 100 kg N and 50 kg P2O5 /ha using variety Tsedey92 was recommended for the farmers of the study area.