Effect of temperature and rearing method on development and fecundity of Tetranychus urticae (Acarina, Tetranychidae)
Prakash Rao, P.; Praslicka, J.; Sutakova, G.
Biologia (Bratislava) 51(5): 509-516
1996
ISSN/ISBN: 0006-3088 Accession: 002818353
The effect of temperature on the development and fecundity Tetranychus urticae was studied applying three mite-rearing methods: A - the live leaf culture method, B - the leaf disk method, and C - the detached leaf culture method. Phaseolus vulgaris was used as the food source. The study was conducted using all combinations of the three rearing methods and three temperatures (20, 25 and 30 degrees C). Both temperature and rearing methods were found to be key elements influencing the life history of T. urticae. The duration of the quiescent and active stages and the life history components, i.e. net reproductive rate (Ro), intrinsic rate of natural increase (rm), generation time (G) and doubling time of the population, were investigated. In all rearing methods rising temperature caused a shortening of the adult lifespan. Using method A the fecundity of mite females decreased with increasing temperature. Fecundity was high using each combination of 30 and 20 degrees C with rearing method B and C. However, the application of these methods at 25 degrees C reduced mite fecundity. Out of all the experiments, the highest number of eggs laid by a female per day (16.4) was observed in method C at 30 degrees C. Prolonged development of all stages was observed at all three investigated temperatures in method B. Neither temperature nor the rearing method influenced significantly the sex ratio of the spider mite progeny. On average, 86.2% of the spider mite eggs developed to adult stages in all rearing methods except method C at 30 degrees C, where less than 66.2% of the eggs reached adult stage. With rising temperatures in all rearing methods, the rm increased and the generation time, as well as the doubling time of the population, decreased.