Author : Soehartini Riyanto

Summary : The study was conducted to determine the effects of different control Methods (handweeding twice, mulching and 2,4-D application followed by handweeding and nitrogen levels (0,45,90 and 135 kg N/ha) on grain yield and other agronomic characters of three sorhum varities (Cosor 1, Cosor 2 and Cosor 3) growth after paddy rice.

Among the three weed control methods, handweeding at 1 and 30 days after seedlong emergence effectively suppressed the weeds, resulting in longer panicles. more grain per panicle, and higher panicle and grain yields.

Higher nitrogen levels up to 90 kg N/ha resulted in carly matuntry, more grains per panicle and higher grain yield. Plant height, panicle length, panicle yield and total dry matter increased with increasing nitrogen level up to 135 kg N/ha. However, increasing nitrogen levels depressed the 100 grain weight.

Grain yield was found positively correlated with plan height, toltal dry matter, panicle yield, number of grain per panicle and panicle lenght, but not with 100 grain weight.