Variability of Some Morpho-Physiological Characteristics of Weedy Rice in Ampara District of Sri Lanka

Abstract

Weedy rice is considered as one of the most troublesome, difficult-to-manage and economically damaging weed in Sri Lanka. Weedy rice affects the growth, yield and quality of cultivated rice. However, weedy rice may contain important genes which can be incorporated into the cultivated varieties. Therefore, study on morpho-physiological characteristics of weedy rice are important to adopt efficient control measures and it may also be helpful to rice breeders in developing new rice varieties. Therefore, this study was aimed to determine the morpho-physiological diversity of weedy rice in Ampara district. Ampara, Akkareipattu and Lahugala locations from Ampara districts were selected as sampling sites.Weedy rice populations representing locations were grown in a common field in a complete randomized design with four replications. Plant height, thousand grain weight, own length, number of spikelet per panicle, number of filling seeds per panicle, number of unfilled grains per panicle, number of shattered seeds per panicle were measured and germination percentage and seed viability were tested. Significant variations were observed in measured characteristics of weedy rice populations in Ampara District. Number of shattered seeds per panicle showed the highest variability (CV-76.7%) compared to all the other characteristics. Significant differences among three populations for all the measured characteristics except for plant height and viability percentage were observed. Measured characteristic of Lahugala population were very similer to that of wild rice and significantly differed from those from other two locations.