MAIZE STREAK VIRUS - EVIDENCE FOR RESISTANCE AGAINST CICADULINA-MBILANAUDE, THE MAIN VECTOR SPECIES

Settling, probing and oviposition behaviour of Cicadulina mbila, the m ain vector of maize streak virus (MSV) disease were studied on four ma ize genotypes, 100MSR, HASR, Reunion and H512. Of the four, only H512 was completely susceptible to MSV while the other three genotypes were all known to have some resistance to MSV. Generally C. mbila settled in higher numbers on the MSV susceptible genotype compared to the thre e virus resistant ones. However, the number of probing marks left on H 512 and 100MSR were similar while more marks were made on Reunion and HASR in increasing order. The oviposition patterns were similar to tho se observed for probing behaviour. The results suggest the existence o f potentially useful resistance mechanisms against the vector. The pos sible implications of these results are discussed.