Does the Lorryia formosa Cooreman (Acari: Prostigmata: Tydeidae) population visit or reside on citrus foliage?

摘要

To explain the sporadic appearance of Lorryia formosa Cooreman (Acari: Tydeidae) on grapefruit and its consistent presence in orange agroecosystems of northeastern Mexico, an experimental study was designed in which field-collected mites from orangeand grapefruit were reared on respective leaf substrates under laboratory conditions. Developmental stages and life table parameters for this rnrte on both host leaves were estimated. The results indicated that on orange, the immature and adult stages of this mite developed 15 and 20 percent faster respectively, compared with grapefruit. The population of this mite on orange increased almost 43 percent per generation, had a positive r_m and required a period of 89.2 days to double its abundance. On grapefruit, the L. formosa population declined by about 45 percent per generation, and it had a negative r_m indicating that its population reduces to one half within 54.4 days. Adult females made up 70 percent of the population on orange compared with only38 percent on grapefruit. These data indicate that a L. formosa population is capable of surviving and reproducing on both of these plants, but its population increases only on orange. We conclude that L. formosa is probably a casual visitor to grapefruit and a resident of orange.