EFFECT OF VARIETY ON YIELD AND NUTRITIVE VALUE OF RICE STRAW

Seven varieties of rice were cultivated in the field of BLRI of which three were native (Maloti, Nizershail and Chandrashail) and four were improved ($BR_3$, $BR_{11}$, Pasam and Mala). Yields of straw and grain were recorded and the chemical composition of straw was determined. Both the grain (p < 0.05) and straw (p > 0.05) yields were higher in the improved than the native varities. Relationships of straw dry matter yield with the hights of rice plants, tiller numbers, levels of N fertilizer and lengths of stover were found to be statistically insignificant. No significant differences were observed among the varieties in respect of NDF, cell soluble, cellulose and hemicellulose contents. However, modified acid detergent fibre and insoluble ash content were significantly (p < 0.05) higher in the local varieties. Except $BR_3$, the estimated ME content of straw was higher in the improved than the native varieties. In respect of yield, chemical composition and energy content improved straws were better and Pasam was the best.