Effects of nutrition on the biology of the Asian citrus psyllid, Diaphorina citri

Effects of nutrition on the biology of the Asian citrus psyllid, Diaphorina citri

 

Tsagkarakis, A.E., A.W. Schumann and M.E. Rogers

University of Florida, IFAS, Citrus Research and Education Center, Lake Alfred, FL, USA.

 

The biology of phytophagous insects, such as aphids, pear psylla and South African psyllid, has been shown to be closely related to the nutritional status of their host plants. Past studies have demonstrated that increased nitrogen fertilization resulted in higher levels of soluble nitrogen in plant leaves, which affected insect biology. The effect of plant nutrition on the biology of the Asian Citrus Psyllid (Diaphorina citri Kuwayama) has previously not been determined. In greenhouse experiments, duration and viability of immatures, adult longevity and reproductive capacity and adult weight were determined for D. citri which developed on plants of varying nutritional quality. ’Valencia’ orange plants were potted individually in plastic containers using sand only as potting media to allow better manipulation of plant nutritional status. Five different fertilization treatments, consisting of high and low nitrogen and potassium levels in all their combinations, were applied using liquid fertilizer to the root zone of each plant. A replicate of unfertilized plants served as a nutrition deficient control treatment. Adult D. citri, from a colony reared on “Valencia” orange plants, were caged on test plants for oviposition. Adults were then removed and the emerged nymphs were checking daily for ecdysis and survivorship. A pair of emerged adults was re-caged on different plants and the total number of eggs laid was counted daily to determine fecundity rate. Every 3 days the pair was moved to new plant to have available the essential space to oviposite. Results and discussion will be presented.