Sowing Date and Insecticide Trials with Selected Multi-Adversity Resistant Cotton Varieties in the Northern Guinea Savanna of Nigeria

Abstract

ABSTRACT Field Trials were conducted during the wet seasons of 1996–1998 on the farm of the Institute for Agricultural Research, Samaru to evaluate some selected multi-adversity resistant varieties of cotton (Gossypium hirstum L.) grown under three sowing dates and insecticide sprayed and unsprayed conditions. The use of insecticide reduced leaf roller (Sylepta derogata) incidence and improved the growth and yield of all the varieties evaluated. Delay in planting up to July 27 reduced leaf roller incidence as well as the yield, plant height, number of bolls per plant and percentage of mature bolls of cotton compared to the mid-June and early July sowing dates in both the sprayed and unsprayed trials. In the sprayed trials, none of the MAR varieties out-yielded SAMCOT-9, the local check. In the unsprayed trials, TX-CABCS-1-81 out-yielded SAMCOT-9 in the three years and TAMCOT-CAMD-E and TX-CDP37-HH-1-83 in 1997 and 1998. TAMCOT-CAMD-E and TX CDP37-HH-1-83 out-yielded SAMCOT-9 in 1996. The trend showed that, without insecticide spraying, TX-CABCS-1-81 and to a lesser extent, TAMCOT-CAMD-E and TX CDP-HH-1-83 have greater resistance to pest adversity than SAMCOT-9.