Role of root and yield characters under drought stress in rice (Oryza sativa L.)

Drought is the major constraint to rice production and yield stability in rainfed areas. Association analysis was performed in F₁ generation of rice in order to understand the nature and extent of association among various traits and grain yield under drought stress condition. Grain yield per plant had positive association with number of productive tillers per plant, root length and root volume. Panicle length had positively correlated with 1000 grain weight, biomass yield, root length and root volume. Among root traits, dry root weight recorded highly positive significant association with root: shoot ratio, root length, root thickness and root volume. Root traits viz., root volume, root thickness, root length, dry root weight and root length density were the major contributors of grain yield by way of their positive and high indirect effects.