Interaction between seed rates, weed population and yield performance of field grown irrigated rice variety Cv. At362

Abstract

Rice (Oryza sativa L.) is an important economic food crop in Sri Lanka. Weeds are a major constraint to the success of rice production. Cropweed competition has a profound effect on the grain yield of rice. However, using herbicides alone may not be considered sustainable in the long term. Hence, a field experiment was conducted at Rice Research Station, Sammanthurai to study the interaction between seed rates - weed population and yield performance of field-grown At362 rice variety. The treatment (T) consisted of six seed rates viz; 2 bushel/ac, 2.5 bushel/ac (as control), 3 bushel/ac, 3.5 bushel/ac, 4 bushel/ac and 4.5 bushel/ac. The field experiment was laid out in Randomized Complete Block Design (RCBD) with 6 treatments having 3 replications. Field data were collected on weed populations, rice crop growth and yield parameters throughout the cultivation season under field conditions. According to the results, plant height, the number of leaves per plant, root length, panicle length and number of panicles were significantly (p<0.05) affected by different seed rates. Lower seed rates resulted in increased values for the above-tested parameters in the At362 rice plant. Sedges were the most dominant weeds in this field plot compared to grasses and broad leaves. However, no significant differences were observed in the yield and weed population (p>0.05). Further research in various seasons and regions can offer a more thorough comprehension of the relationship among rice seed rates, weed dynamics, and yield.