The effect of intercropping with maize on the level of infestation and damage by pod-sucking bugs in cowpea

The effect of intercropping cowpea (Vigna unguiculata(L) Walp.) with maize (Zen mays L.) on the population of cowpea pod-sucking bugs (PSB) was invest igated by varying the time of planting cowpea in cowpea/maize intercropping systems. The different planting times were simultaneous planting of maize and cowpea (0) and subsequent interplanting of cowpea at 2, 4, 6 and 8 week s after planting (WAP) maize. The ratios of cowpea:maize population was als o varied. The population of Clavigralla tomentosicollis Stal., Riptortus de ntipes Fab., Anoplocnemis curvipes Fab., Mirperus jaculus W. and Nezara vir idula L. was significantly less on cowpea in the 4 and 6 WAP treatments., b ut yield in these treatments was also reduced compared to all other treatme nts. There was a significantly lower population of bugs (P < 0.05) on the c owpea crop when grown at 25:75 and 50:50 cowpea:maize ratios but the yield was greatest at the 50:50 ratio. (C) 2001 Elsevier Science Ltd. All rights reserved.