Vol. 12, Issue 6 (2023)

Author(s):
Rashmi Gauraha, Jayalaxmi Ganguli and Yogesh Meshram

Abstract:
Aphid mummy, Diaeretiella rapae (Mclntosh) parasitizes more than 60 aphid species among which five to six species are common pests that attack agricultural and horticultural crops. This study was designed and conducted during 2019-20 and 2020-21 in the Bio-control laboratory, IGKV, Raipur, Chhattisgarh to find out maximum percent adult survival and longevity under three levels of storage temperature (viz.,4 ˚C, 9 ˚C, 12 ˚C and Control (20 °C) with storage durations of (one to five weeks) Significantly maximum survivability of emerged adult parasitoid, D. rapae from mummified aphids (84.52%) and highest adult longevity (9.00 days) were recorded at in controlled conditions while lowest percentage of adult emergence (21.18 %) was recorded in five weeks of storage. Higher adult longevity was found in control (8.96 days) followed by one week of storage (8.40) days. Adult longevity further declined to 8.60, 7.58, 6.78, 5.00 and 4.20 days with 1, 2, 3, 4 and 5 weeks of storage. There was significant reduction in emergence with time. It was observed that approximately 7.00% reduction in adult emergence was seen after one week of storage (78.60%) as compared to control (84.50%). Significantly lowest adult emergence was observed in five weeks of storage (19.00%) at 4 ˚C. Only 50.00 percent survivability of mummified aphid was recorded after two weeks of storage duration. Maximum survivability was recorded at 9 ˚C and 70-75% RH of one weeks of storage (74.20%). Adult longevity was observed highest in control (8.80 days) which was on par with one week of storage (8.40 days). Highest percent of adult emergence was recorded in one week of storage (72.20%) but in control treatment adult emergence was greater than that of one week of storage (76.40%). Highest survival percent and adult emergence after storage of mummified aphid, D. rapae were recorded under controlled conditions ie at 20 ˚C followed by 4 ˚C, 9 ˚C and 12˚C one week after storage. Hence for the storage of mummified aphids, higher temperature 20 ˚C seemed to be better. Percent reduction in survival was observed minimum in one week of storage & it was maximum in 5th week of storage duration.