Bemisia argentifolii (Homoptera : Aleyrodidae): Factors affecting adult and nymph honeydew production

Laboratory studies were conducted to determine the quantity and quality of the major honeydew sugars produced by Bemisia argentifolii Bellows and Perr ing (= B. tabaci strain B) (SPW) adults and nymphs. The effects of temperat ure, light intensity, and SPW adult density on honeydew production were als o determined. In the field, we studied the effects of insecticides on SPW p opulations and on honeydew production of adults and nymphs collected in tre ated and untreated cotton plots. In the laboratory, adult females lived lon ger than males, produced more and larger honeydew drops, and, in most cases , larger amounts of the measured honeydew sugars compared with males. Both male and female adults produced more honeydew at 26.7+/-1 degrees C and 32. 2+/-1 degrees C compared with 21.1+/-1 degrees C. Under our conditions neit her light intensity (30 or 450 mu mol/second/m(2), respectively), nor adult density affected honeydew production. SPW development from egg hatch to ad ult emergence averaged 12.2 days at 26.7+/-1 degrees C. Honeydew production began the first day of nymphal life and peaked on day 3 following emergenc e. First and second nymphal instars produced more drops than third and four th nymphal instars. However, honeydew drop size was larger for third and fo urth instars compared with first and second instars. The third and fourth i nstars produced more trehalulose compared with the earlier instars. Adults produced more honeydew than nymphs. Trehalulose as a percentage of all suga rs measured in the study was greater for adults compared to nymphs Melezito se, as a percentage of all measured sugars, was greater for nymphs compared with adults.