干旱区生态环境知识资源中心

Selected cultivars and breeding lines of Pima cotton, Gossypium barbadense L., and Upland cotton, Gossypium hirsutum L., were evaluated for susceptibility to Bemisia argentifolii Bellows and Perring under the desert growing conditions in Imperial Valley, C.A, in 1990 and 1991. Results in three of four experiments showed that Pima cottons had higher whitefly populations than Upland cottons studied. Within each cotton species, whitefly populations on the different cultivars and breeding lines were not significantly different. Pima cotton, in general, yielded less than Upland cotton. Lower lint yields in 1991 than in 1990, for the same cottons grown in each year, were associated with higher whitefly populations. None of the cottons tested showed resistance to B. Argentifolii of economic significance Results emphasize the need to identify resistance mechanisms and initiate breeding programs to incorporate resistance into acceptable agronomic cottons.