Age and Stage-Specific Life-Table of Cabbage Butterfly, Pieris Brassicae L. (Lepidoptera: Pieridae) on Various Cole Crops

摘要

Age and Stage-Specific Life-Table of Cabbage Butterfly, Pieris Brassicae L. (Lepidoptera: Pieridae) on Various Cole CropsTo study the response of cabbage butterfly, Pieris brassicae on cabbage, cauliflower, yellow sarson, gobhi sarson and Indian mustard, various life tables i.e., age specific and stage specific life tables have been constructed in controlled conditions (25±1°C, 65±5% R.H. and 12 h L:12 h D). The age specific life-table revealed that P. brassicae required maximum period of 42 days on Indian mustard and minimum 36 days on cabbage to complete the generation. The survivorship decreased gradually from an initial stage of development till culmination of the generation on each host plant. However, mortality showed a significant variation at different development stages of P. brassicae on each host plant. The apparent mortality and mortality survival ratio was found highest at pupal stage (15.91 and 0.19%) on Indian mustard and lowest at pre-pupal stage (3.39 and 0.04%) on cabbage. Similarly, maximum k-value (0.0753) was recorded at pupal stage on Indian mustard and minimum (0.0150) at pre-pupal stage on cabbage. On the other hand, survival fraction was recorded highest (0.97) at pre-pupal stage on cabbage and lowest (0.84) at pupal stage on Indian mustard. The life-table parameters revealed that cabbage is the most preferred food of P. brassicae than other cole crops.