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PRINT ISSN : 2319-7692
Online ISSN : 2319-7706 Issues : 12 per year Publisher : Excellent Publishers Email : editorijcmas@gmail.com / submit@ijcmas.com Editor-in-chief: Dr.M.Prakash Index Copernicus ICV 2018: 95.39 NAAS RATING 2020: 5.38 |
The biology of the mealybug Phenacoccus solenopsis Tinsley studied on Bt cotton under laboratory conditions at Department of Entomology, N. M. College of Agriculture, Navsari Agricultural University, Navsari during September to November 2010 with the average room temperature of 28.37 ± 1.51°C and relative humidity of 60.63 ± 2.40 per cent. The incubation period of the eggs ranged from 30 to 56 minutes with an average of 42.04 ± 7.81 minutes. The duration of first, second and third instar nymphs was 6.40 ± 1.10, 8.45 ± 0.82 and 5.70 ± 1.81 days in male and 7.00 ± 0.92, 7.85 ± 1.04 and 6.45 ± 1.15 days in female, respectively. The quiescence period of fourth instar in male (cocoon) was 5.35 ± 1.18 days. The total nymphal period of male and female nymphs was 25.90 ± 2.57 days and 21.30 ± 2.23 days, respectively. Average pre-oviposition, oviposition and post-oviposition periods was 5.90 ± 0.80, 17.60 ± 4.03 and 9.45 ± 1.11 days, respectively. The female oviposited on an average 328.70 ± 120.07 eggs in groups within the cottony mass (ovisac) during its oviposition period. Average longevity of male was 3.85 ± 0.88 days while of female as 32.95 ± 4.56 days. Female adult lived longer than male adult. The sex ratio of male: female was found to be 1: 3.68 as observed while rearing in the laboratory and it was 1: 3.16 as observed from the field collected populations indicating preponderance of female over male. The total life cycle of males of P. solenopsis occupied on an average 29.75 ± 2.77 days ranging from 25 to 34 days in male and 54.25± 4.95 days ranging from 45 to 60 days in female.