Department of Biological Sciences, Rivers State University of Science and Technology, Nkpolu, Port Harcourt, Nigeria.
* Address for correspondence: O.K. Ogbalu, P.O. Box 1698 Port Harcourt, Rivers State Nigeria.
Online published on 29 October, 2012.
The feeding index, feeding severity and preference ratio of adults R. dentipes were investigated in ten cowpea varieties (IT84S -2246-4, IT86D-715, IT86D-1010, IT87D-94-1 OBRIKOM-l84 IT87D1134, IT82D-789, IT84S-124, L-80 and He Brown). The number of seeds attacked and the degree of penetration were compared with those of the susceptible and resistant controls (IT84E -124 and IT82D -789 respectively). Extensive feeding was obtained on IT86D -1010, IT87D -941 -I, OBRIKOM -184, and He Brown, Their preference ratio (PR) was very high as against the low values for IT86D -715 and IT84S -2246 -4. The preference ratio for the susceptible check, IT84E -124 was significantly higher than that for the resistant check, IT8D -789 W<0.05). Two varieties IT84S -2246 -4 and IT86D -715 elicited poorer response to R. dentips feeding. The positive feeding response in the susceptible varieties (OBIRIKOM -184, He Brown, IT87D -941-1 and IT86D -1010) significantly differed from those of the resistant varieties (P<0.05).
