Host use of sympatric Yucca species by Arpediothrips mojave Hood (Thysanoptera: Thripidae).

摘要

Yucca plants were sampled for brachypterous Arpediothrips mojave at two sites 13 km apart along the southward-ascending Walking Box Ranch Road, 19 km southwest of Searchlight, Clark County, Nevada, USA. The lower site supported Y. brevifolia and Y. schidigera at an elevation of 1245-1290 m on the east slope of the New York Mountains. The upper site supported Y. brevifolia and Y. baccata at an elevation of 1377-1405 m in a valley between the east slope of the New York Mountains and the west slope of the Castle mountains. Y. brevifolia was distributed continuously, while Y. schidigera and Y. baccata overlapped in distribution, between the two sites. Thrips were sampled on 12 plants of each Yucca spp. at each site during 5-12 May 2004 and 2-8 March 2005. A total of 280 brachypterous A. mojave, 17 males and 263 females, were collected on 126 Yucca leaf clusters during 2004. Thrips were more abundant during 2005, when 1388 brachypterous specimens, 9 males and 1379 females, were collected on 127 leaf clusters. During 2004, thrips inhabited a greater proportion of clusters on Y. schidigera compared with Y. brevifolia at the lower site and one Y. brevifolia compared with Y. baccata at the upper site. During 2005, when thrips were more abundant, proportions of inhabited clusters were greater on Y. brevifolia compared with Y. baccata at the upper site but were not significantly different between Y. schidigera and Y. brevifolia at the lower site. Overall, results suggest that host use by A. mojave was greatest on Y. schidigera, intermediate on Y. brevifolia, and least on Y. baccata..