Resistance in upland cotton to the silverleaf whitefly transmitted cotton leaf crumple disease

摘要

Eight cotton, Gossypium hirsutum L., cultivars or breeding-lines were evaluated in the field for resistance to the silverleaf whitefly, Bemisia argentifolii Bellows and Perring, transmitted cotton leaf crumple (CLCr) disease caused by cotton leaf crumple geminivirus (CLCrV) in Imperial Valley, CA. The cultivars were Texas 121, AP 4103, AP 6101 and Stoneville 474 and the breeding-lines were DG 2165, DG 2108, DG 2383 and DG 2387. Cotton entries were rated for severity of CLCr disease symptoms. Leaf and petiole samples from each entry were used to confirm the presence of CLCrV by squash and dot blot hybridization with a general DNA probe, which detects the presence of whitefly transmitted geminiviruses. DNA sequencing of a PCR amplified fragment from an infected plant was used to confirm that the geminivirus was CLCrV. Results showed differences in whitefly infestation levels and virus disease symptoms among cotton entries. The variety Stoneville 474, with hirsute leaves, had more silverleaf whitefly adults and nymphs than any of the other entries. The breeding-lines DG 2383 and DG 2387, with Cedix parentage, had a lower CLCr disease rating than other entries.