Effect of Irrigation Scheduling on Forage Yield and Quality of Rhodes Grass and Common Vetch under Water Stress Conditions

This study examined the effects of different irrigation intervals (7, 14, 21, and 28 days) on the growth, yield, and quality of Rhodes grass (Chloris gayana) and common vetch (Vicia sativa L.) under field conditions in Sana'a Governorate, Yemen, during two growing seasons. A randomized complete block design with a split-plot arrangement was employed. Short irrigation intervals (7 and 14 days) significantly enhanced plant height, fresh weight, and dry matter yield in both forage species, whereas moderate water stress (21 days) increased crude protein concentration. Rhodes grass showed higher biomass production, while common vetch achieved superior forage quality, reflected in higher leaf/stem ratio and crude protein content. Significant interactions between irrigation intervals and plant genera were observed for most traits. The study concludes that optimizing irrigation scheduling according to forage species can improve productivity and quality under water-limited conditions.