Biology and life table of spider mite, Tetranychus macfarlanei baker and pritchard (Acari: Tetranychidae) on cucumber
Latha M, Manjunatha M, Chinnamadegowda C and Kalleshwaraswamy CM
The life history of Tetranychus macfarlanei Baker and Pritchard on cucumberleaflets was studied at 25.00 ± 2.00 0C, 80 ± 5 per cent R.H. Life table parameters of T. macfarlanei was conducted at four different constant temperatures, 20 0C, 25.3 0C (lab. temperature during June-December 2018), 28 0C and 32 0C on leaves of cucumber with 16h: 8h L:D conditions in a BOD incubator. The results indicated that the total duration from egg to adult emergence was less in male (9.67 ± 0.69 days) as compared to female (11.65±0.77 days). The adults of T. macfarlanei reproduced sexually and parthenogenetically. During the total oviposition period, mated female laid 50.23±6.32 eggs while unmated female laid 21.13±4.89 eggs. The total life cycle from egg stage till death of mite showed that the males completed life cycle earlier within 24.90±1.98 days while females required 31.40±0.98 days. There was higher survival rate for T. macfarlanei at lower temperature (20 â°C), as well as at moderate temperature (25.3 â°C) compared with highest temperature of 32 â°C and 28 â°C. An average fecundity of mated females was highest (53.20 eggs) at 28 â°C. The innate capacity of increase (rm) and finite rate of increase (λ) of T. macfarlanei reached maximal values (0.123 and 1.131) at 32â°C. The mean generation time (T) and doubling time (DT) were shortest (12.31 and 2.43) at 32 â°C followed by 28 â°C (14.78 and 2.75) and longest (20.07 and 6.60) at 20 â°C. The net and gross reproductive rates were maximum at 28 â°C (40.97 and 55.22). The overall results suggested that T. macfarlanei could develop and reproduce within a wide range of temperatures. The range 28-32 â°C was the most suitable for the development, survival rate and reproduction of the spider mite.
Latha M, Manjunatha M, Chinnamadegowda C, Kalleshwaraswamy CM. Biology and life table of spider mite, Tetranychus macfarlanei baker and pritchard (Acari: Tetranychidae) on cucumber. J Entomol Zool Stud 2019;7(5):1050-1057.