ABSTRACT

We compared okra- and normal-leaf upland cotton (Gossypium hirsutum L.) strains and cultivars and okra-leaf wild cotton (Gossypium thurberi L.) for susceptibility to colonization by silverleaf whitefly Bemisia argentifolii Bellows and Perring. Experiments were conducted at three locations at Holtville, CA during 2001 and 2002. Okra-leaf strains and cultivars, as a group, had lower numbers of adults, eggs and nymphs compared with normal-leaf cultivars indicating the potential of okra-leaf genetic traits for reducing colonization by B. argentifolii. The hairy-leaf cultivar ‘Stoneville 474' had more adults, eggs and nymphs than smooth leaf strains and cultivars. Results suggest that okra-leaf and smooth leaf cotton may provide less favorable microclimate conditions for B. argentifolii habitation. The okra-leaf cultivar ‘Siokra L23' appears to have genetic traits that should be examined further as a source of B. argentifolii resistance.