Effect of different variegated leafcroton to the growth and reproduction of ‘CV ’ biotype Bemisia tabaci

Key Words：CV biotype Bemisia tabaci, development, reproduction, variegated leafcroton

Abstract：         The CV biotype of Bemisia tabaci(Gennadius) is a serious pest of ornamental plants. The effect on the growth, survival and reproduction of this biotype of three kinds of variegated leaf croton (Codiaeum variegatum ‘Aucubaefolium’, C. variegatum nov. and C. variegatum ‘Mons-florin’ ) was studied under husbandry conditions of （26±1）℃, 75%-90% relative humidity and L∶D＝14∶10. The longest developmental time, 32.80 days, was recorded on C. variegatum ‘Aucubaefolium’ followed by C. variegatum nov. (29.70 days) and C. variegatum ‘Mons-florin’ (29.45 days). Insects on different plant varieties differed significantly in total survivorship from egg to adult. Survivorship was highest on C. variegatum ‘Mons-florin’ (58.82%), intermediate on C. variegatum nov. (46.54%) and lowest on C. variegatum ‘Aucubaefolium’ (40.53%). The longest preoviposition period (0.79 days) was recorded on C. variegatum ‘Aucubaefolium’. Adult longevity was longest (14.89 days) on C. variegatum ‘Mons-florin’. There was no significant difference in average fecundity per female on the different plant varieties; the highest was recorded on C. variegatum ‘Aucubaefolium’(381 eggs/female). Intrinsic rates of natural increase (rm) on Codiaeum variegatum ‘Aucubaefolium’, C. variegatum nov. and C. variegatum ‘Mons-florin’ were 0.0397、0.0625 and 0.0860, respectively. All three varieties of variegated leaf-crotons were the suitable host plants for the development and reproduction of the CV biotype of B. tabaci.