Abstract: 【Aim】 Our previous study revealed that two calcium-binding proteins (BtCaBP1 and BtCaBP2) are involved in the stress response of Bemisia tabaci MED to cyantraniliprole. This study aims to systematically reveal the biological effects of calcium-binding proteins on B. tabaci MED by RNAi of their genes. 【Methods】 After knocking down the calcium-binding protein genes BtCaBP1 and BtCaBP2 in B. tabaci MED adults by feeding dsRNA, the expression levels of the two genes were determined by qPCR. The biological parameters including the longevity (female and male) and fecundity of adults, and the egg hatching rate and pre-adult duration of offspring of B. tabaci MED between the control group (feeding on dsEGFP) and the treatment group (feeding on dsBtCaBP1 and dsBtCaBP2, respectively) were observed and compared after RNAi for 3 d. 【Results】 After feeding on dsBtCaBP1 and dsBtCaBP2, respectively, for 3 d, the expression levels of the target genes BtCaBP1 and BtCaBP2 of B. tabaci MED adults decreased significantly as compared with those in the control group. Compared with the control group, the dsBtCaBP2 treated-group had significantly increased the longevity (female: 15.46±1.24 d vs 13.25±0.58 d; male: 13.84±0.38 d vs 12.67±0.65 d), significantly decreased the number of eggs laid per female (39.53±3.04 vs 76.06±4.76), significantly decreased the egg hatching rate of offspring (81.58%±4.42% vs 87.22%±3.21%), and significantly shortened the pre-adult duration of offspring (24.42±1.09 d vs 27.52±1.73 d). However, feeding on dsBtCaBP1 had no significant effect on the above biological parameters of B. tabaci MED. 【Conclusion】 The RNAi of BtCaBP1 and BtCaBP2 has different biological effects on B. tabaci MED, and this finding will be helpful to reveal the function of CaBPs.

Key words: Bemisia tabaci MED, calcium-binding protein, RNA interference, fecundity, developmental duration