EVALUATION OF SOME COWPEA GENOTYPE~ TO INFESTATION OF CERTAIN PIERCING SUCKING INSECTS AND COTTON LEAFWORM IN KAFR EL-SHEIKH REGIQN

Document Type : Original Article

Authors

1 Agric. Res. Center, Plant Protect. Res. Inst., Sakha Agric. Res. St

2 Entomology Dept. Fac. of Agrlc. Kafr EI-Shelkh, Tanta University

Abstract

The study was conducted at the experimental fann of Ihe Faculty of
Agriculture, Kafr EI-Sheikh. Experiments were carried out on different geno pes of
cowpea In two summer plantations, being 2001 and 2002.
Results showed one to three peaks of A crecdvote, 8. labaci, Empoasca
spp., N. viridula and S. littoralis were recorded on the different genotypes of cowpea
during July, August and September in the two successive seasons. The genotype (It
92 KD·357-2) harboured the highest population of beneficial arthropods and ~ad the
least infestation with Acraccivora and S. littora/is in both seasons. Statistical analysis
indicates highly significant positive correlation (r = 0.45) between Chrysoperla eamea
and 8. I8baci (adult) populations while it was insignificant between C. camea and the
remaining insect species in 2001 season. In 2002 season significant negative
correlation (r = .0.38) between C. camea and A. cracciVora was recorded while it was
insignificant between the predator and the remaining insects.
Results indicated that (It 95 K·2011·11) and (It 82·E·16) genotypes were less
infested with the cowpea aphid, Aphis craccivora Koch., while (It Brown) ge~otype
was more favourable to infestation. The genotypes (It 83.-911) and (It 86q-880)
attracted high numbers of the adults of cotton whitefly, 8emisia labaci (Gann.), but (It
98 K·573-3) and AzmerJy were the least infested one. Genotypes (It 95m.120) and (It
66 F·2062·5) harbored the least numbers of [assids: Empoasca spp., while (It Brown)
and (It 85k-105·2) genotypes were the most susceptible to infestation with the ~reen
stink bug; Nezara viridula (L.). The highest numbers of cotton leafworm; Spodoptera
I
Utoralis (Botsd.) were recorded on (It 840-448), while (It 95K-1088-4) genotype had
the lowest infestation rates.