Oviposition Patterns of Creontiades signatus (Hemiptera: Miridae) on Okra-Leaf and Normal-Leaf Cotton

摘要

We investigated the oviposition behavior of Creontiades signatus Distant (Hemiptera: Miridae), a relatively new plant bug pest of south Texas cotton, Gossypium hirsutum L., on okra-leaf and normal-leaf genotypes that differed significantly in their leaf morphology and trichome densities. In a no-choice study, the site preference and numbers of eggs oviposited by C. signatus were identical for the okra-leaf and normal-leaf. In a free-choice test, C. signatus showed a significant preference for the normal-leaf by ovipositing 3 times the number of eggs than on okra-leaf, but the site locations and percentages of egg distributions were similar for the two cotton types. The leaf petiole was the most preferred site for oviposition, followed by the main stein, and fruiting structures (squares and small bolls). The majority of eggs were oviposited in the leaf petioles associated with the mid-portion (nodes 4 - 8) of the plant. Trichome densities on the leaf petioles, main stem, and leaf veins were similar for node 3, but they were significantly higher on these structures for nodes 5 and 8 for the okra-leaf compared with the normal-leaf. The strong selection of oviposition sites in the normal-leaf cotton in this study may be due to some factor other than trichome density. This information should increase the knowledge for scouting for the presence of eggs and young nymphs and serve as a starting point for the selection of nonpreferred cotton varieties for oviposition by this mirid.