|Chu, Chang Chi|
Submitted to: Sweetpotato Whitefly Progress Review Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 4/1/2002
Publication Date: 6/1/2002
Citation: Interpretive Summary:
Technical Abstract: Sixteen upland cotton, Gossypium hirsutum L., cultivars and experimental breeding-lines were evaluated in the field for susceptibility to silverleaf whitefly, Bemisia argentifolii Bellows and Perring, sown at the UC Desert Research & Extension Center, Imperial Valley, CA, into plots of a randomized complete block design experiment replicated four times, and irrigated 24 March 2000. The normal leaf cultivars were DP 20, DP 50, DP 90, DP 5415, DP 5432, DP 5461, DP 5557, HCR 9257, HCR 9240, and Stoneville 474 and the okra-leaf cultivars and experimental breeding-lines were Siokra L23, FiberMax 832, FiberMax 819, E1028, E0798 and E0223. Individual plots measured 14 m in length with 8-beds on 1 m centers or 8m wide. Silverleaf whitefly adults were sampled from ten plants at random in each plot via the leaf turn method using the 5th main stem leaf from the terminal. Silverleaf whitefly nymphs were counted on 1.65 cm^2 leaf disks of from ten 5th position leaves down from the terminal extracted from randomly selected plants in each plot. Adults and nymphs were sampled on 23 & 29 May, 5, 12, 19, & 26 June, 3, 10, 17, 24 & 31 July, 7, & 14 August, 2000. on 30 June, 7, 14, 20, 28 July, 4, 11, 18, & 25 August. Seed cotton was hand picked from 0.002 acre per plot and yield data were recorded. The okra-leaf entries as a group had fewer silverleaf whitefly adults and nymphs than the normal leaf cotton entries. The okra-leaf experimental breeding-lines had the lowest numbers of silverleaf whitefly adults and nymphs among the okra-leaf entries. Stoneville 474, a hirsute leafed cotton, had the greatest numbers of silverleaf whitefly adults and nymphs among the normal leaf cottons.