BIOLOGY OF MEALY BUG (PHENACOCCUS SOLENOPSIS TINSLEY) ON BIDI TOBACCO (NICOTIANA TABACUM L.) * * Babu Lal Jat, D.M. Mehta and L.V. Ghetiya Department of Entomology, B. A. College of Agriculture, AAU, Anand - 388 110 * Bidi Tobacco Research Station, AAU,Anand - 388 110 (Gujarat) ABSTRACT Studies on the biology of the mealy bug, Phenacoccus solenopsis Tinsley was carried out at various temperatures and relative humidity on tobacco at AAU, Anand. The incubation period was 1.4 to 2 days with an average of 1.48 ± 0.45 days. The male and female nymphs of mealy bug passed through four and three nymphal instars, respectively on tobacco. The duration of first instar nymph, second instar nymph and third instar nymphs of female mealy bug was 3 to 6 (4.30 ± 1.02 days), 4 to 8 (5.97 ± 1.15 days) and5.58 ± 0.92 (4 to 7 days), respectively.The male nymphs were found to be forming white silken cocoon after third moulting. The duration of male cocoon was 4 to 6 days with an average of 5.00 ± 0.69 days. The longevity of male and female was 1 to 3 (2.42 ± 0.78 days) and 28 to 34(29.34 ± 1.55 days) respectively.The total life cycle of male and female was 20 to 26 (21.00 ± 2.36 days) and 43 to 54 (47.00 ± 2.50 days). The average pre-oviposition, oviposition and post-oviposition periods were 4.88 ± 1.02, 16.55 ± 1.09 and 7.90 ± 1.21 days, respectively. The average number of eggs laid by a female during its life cycle was 448 ± 85.41 eggs. Key Words:Biology, laboratory, Phenacoccus solenopsis, tobacco Introduction The occurrence of mealy bug (Phenacoccus solani Ferris) on tobacco was recorded by Williams et al . (1985). Phenacoccus solenopsis is a newly emerging pest on tobacco. Present study was undertaken at Bidi Tobacco Research Station, Anand Agricultural University, Anand to generate data on this pest. Materials and Methods To establish initial culture of P. solenopsis, mealy bug infested cotton twigs were collected from the cotton field and they were reared in the laboratory. Pumpkin (Cucurbita sp.) fruit was used for rearing the mealy bug (Nikam et al., 2010). Fresh pumpkin fruit was washed thoroughly with water and kept aside till the water on the surface of the fruit was evaporated. It was then placed in a plastic bowl, the bowl was placed in plastic tray which was then kept in wooden cage. Female mealy bugs were released on pumpkin fruit to allow them to establish and lay the eggs. The newly hatched crawlers were placed individually on tobacco leaves with the help of camel hair brush. These tobacco leaves were placed in glass petri dishes. When crawlers settled on leaves, they were marked by drawing red circle around them. The crawlers thus marked were observed daily for studying till they attended adult stage. Results and Discussion The data recorded on different parameters are presented in Tables 1, 2 and 3. The incubation period of P. solenopsis was 1.4 BIOINFOLET 10 (4 C) : 1458 - 1461, 2013