Effect of date of planting on Striga hermonthica control in Sorghum bicolor.

Abstract

Seeds of six sorghum (sorghum bicolor) varieties (KSV 8, KSV 4, NR71176, NR71182, ICSV111 and local) were sown at different dates at two weeks interval (15 and 27 June, 9 and 21 July) to evaluate the effect of planting date for Striga hermonthica infestation on the crop under field conditions. The experience was laid out in a randomized complete block design with sorghum varieties in the main plots and different dates constituting the sub plot and replicated three times in 1998 cropping season. Results indicate that sorghum varieties significantly differ in Striga shoots density per m2 and sorghum syndrome reaction score. Also at 10 WAS the one sown on 27 June had a lower height than other days among the varieties, varieties NR 711182 and ICSV 111 has a lower height (m) than other varieties. At 18 WAS those sown on 15 and 27 June had a lower height than the other days and variety ICSV 111 has the lowest height than others. The late sown crop generally had lower days to booting than the early sown crops. The early sown crops had higher days to ear formation than late sown ones. The late planting significantly delayed Striga emergency by 4-6 days and correspondingly reduced shoot density by 60%, it also reduced Striga development and enhanced sorghum growth hence resulting in significant increase in sorghum yield by over 70%.