Effect on Temperature Influences of the Life Table Studies for Aphid, Aphis craccivora Koch. in Cowpea under Laboratory Condition

Abstract

Aim: To study the life table aphid, Aphis craccivora in cowpea at different temperature. Study Design: Simple random sampling design with two treatments and 12 replications. Place and Duration Study: Agricultural College and Research Institute, Madurai and  2019-2020. Methodology: We used a simple random sampling design, which included two temperature variables (30 and 35°C) and 12 repetitions for A. craccivora. The female adult aphids were placed in dishes with leaf dishes and 12 hours light appropriate temperature. Female adult aphids were placed in dishes containing leaf discs and incubated at the appropriate temperature, with a 12-hour light phase. They were transferred to new dishes as needed. We evaluated the pre-reproductive and reproductive periods under a stereomicroscope every 24 hours, and we determined the number of nymphs produced and their longevities at each temperature. Results: Aphid, Aphis craccivora Koch. is most important pest in Pulses ecosystem and life table studies on cowpea, the net reproductive rate (22.53  individuals / female at 300 C; 14.23 individuals / female at 350 C, mean generation time 11.41days at 300C; 10.39 at 350C, population doubling time (2.710 days at  300C, 2.539  at 350C in Cowpea. The age specific survivorship curve revealed that the population followed Type III curve and 50 per cent mortality of A. craccivora 9 days at 300C and 7.5 days at 350C in cowpea. Conclusion: The life table aphids insects parameters of net reproductive rate, population doubling time, mean generation time and age specific curve was maximum in 300C than 350C in Cowpea.