Reproductive performance of Plutella xylostella (L.) (Lepidoptera: Plutellidae) on kale and rocket

The objective of this study was to investigate the reproductive performance of Plutella xylostella on 2 varieties of crucifers, kale ‘HS20’ (Brassica oleracea var. acephala) and rocket ‘folha larga’ (Eruca sativa) for 2 generations in the laboratory. The insects used in this study were obtained from P. xylostella reared on kale leaves at the Laboratory of Biology and Insect Rearing (LBIR) of UNESP Campus, Jaboticabal, Sao Paulo, Brazil. We performed 5 replicates for each variety; each replicate was a cage containing one 8-cm-diameter leaf disc for female oviposition. In each cage, we placed 2 pairs of adult male and female P. xylostella, which were observed until death. To evaluate the reproductive performance of P. xylostella, larvae were reared on leaves of kale or rocket for 2 generations. We observed significant differences in fecundity (number of eggs per female) between the generations and varieties of crucifers. The first generation showed a significant difference in fecundity between the crucifer varieties, with a higher number of eggs per female on rocket (243.0 eggs) than on kale (206.8 eggs). However, in the second generation, female fecundity was similar (179.4 and 216.1 eggs per female on kale and rocket, respectively). The pest P. xylostella has high reproductive potential on both kale and rocket, thereby making it difficult to control this pest in gardens where these crucifer varieties are planted side by side.