Biology and Population Dynamics of Two Spotted Spider Mite (Tetranychus urticae Koch) in Cucumber (Cucumis sativus Linnaeus) Under Protected Cultivation
K. Prakash *
Department of Agricultural Entomology, Tamil Nadu Agricultural University, Coimbatore, India.
V. Baskaran
Department of Agricultural Entomology, Tamil Nadu Agricultural University, Coimbatore, India.
E. Sumathi
Department of Agricultural Entomology, Tamil Nadu Agricultural University, Coimbatore, India.
A. Suganthi
Department of Agricultural Entomology, Tamil Nadu Agricultural University, Coimbatore, India.
R. Swarnapriya
Floriculture Research Station, Thovalai, Tamil Nadu, India.
*Author to whom correspondence should be addressed.
Abstract
Two spotted spider mite, Tetranychus urticae Koch is the major polyphagous pest on crops and cause considerable yield loss. Cucumber cultivation become possible throughout the year in closed condition with improved agronomic practices. The cultivation of cucumber under controlled condition is threatened by the occurrence of various pests, of which mites occupied greater importance in yield reduction. The influences of weather parameters on population dynamics of T. urticae were studied under protected condition during autumn season of 2021 and continued till last week of April. The observations revealed that the mite population was significantly increased under closed condition and the recorded total developmental period of mites was 6.47 ± 0.003 days, these changes in the biology might resulted from variation in the weather parameters in closed conditions. The population dynamics of two spotted spider mites differed significantly under the protected cultivation compared to the open field condition and a peak population of mites were observed during the second fortnight of march (16th standard meteorological week) and the lowest population was observed during month of November and December as the results of unfavorable environmental condition.
Keywords: T. urticae, cucumber, weather parameters, polyhouse, improved agronomic practices