Identification of the best seed sowing rates for optimizing grain yield of at-362 rice variety

Abstract

Rice (Oryza sativa L.) is a staple food for a substantial portion of the global population and it is cultivation all over the world. Seed rate has a significant impact on plant population, crop quality and overall yield in paddy cultivation. Hence, this study was conducted to identify the best seed sowing rates for optimized growth and yield potentials of the At362 rice variety in Ampara District, Sri Lanka. Six different seed rates viz; 2 Bu/ac, 2.5 Bu/ac (Control), 3 Bu/ac, 3.5 Bu/ac, 4 Bu/ac and 4.5 Bu/ac were selected for this experiment. The treatments were arranged in Randomized Complete Block Design (RCBD) with three replications. Data on growth and yield related parameters were collected at different time periods and analyzed using SPSS software. The results revealed that most of the tested parameters were significantly (p<0.05) affected by different seed rates. Lower seeds rate (2 Bu/ac, 2.5 Bu/ac and 3 Bu/ac) resulted in increased mean values for growth parameters including plant height, number of leaves produced in the main culm, flag leaf length and width, culm length and root length compared to higher seed rates. Similarly, panicle length and number of filled per panicle were higher at 2.0 and 2.5 Bu/ac respectively. However, the number of panicles/m2 was significantly higher in 4 Bu/ac and 4.5 Bu/ac while the filled panicle and the grain weight were increased in the lower seed rates suggesting that the increasing seed rates marginally increased the panicle production in cv. At362 rice variety.