INFLUENCE OF ABIOTIC FACTOR'S ON THE POPULATION DYNAMICS OF CYDIA PTYCHORA MEYRICK (LEPIDOPTERA : TORTRICIDAE) IN PIGEON PEA UNDER AGRO-CLIMATIC CONDITIONS OF MANIPUR
S. SUBHARAN *
ENTOMOLOGY RESEARCH LAB., DEPARTMENT OF LIFE SCIENCE, MANIPUR UNIWERSITY, CANCHIPUR-795 003, INDIA
T.K. SINGH *
ENTOMOLOGY RESEARCH LAB., DEPARTMENT OF LIFE SCIENCE, MANIPUR UNIWERSITY, CANCHIPUR-795 003, INDIA
*Author to whom correspondence should be addressed.
Abstract
Studies were carried out for two consecutive years on the impact of various abiotic factors on the population build up of Cydia ptychora Meyr. It was found that damage commenced in the flowering stage of the crop with 2.23% and 2.60% in the last week of November in both the years. The peak infestation of the pest 12.69% in the first year was recorded during last week of December whereas it was recorded two weeks later i.e during second week of January with 10.73% infestation in the second year. The infestation then gradually decreased and continued up to third week of February in the first year (3.20%) whereas the pest was found infesting the crop only up to second week of February (3.54%). Correlation studies showed that mean temperature, total rainfall and wind speed had negative association whereas relative humidity and sunshine had positive association with the pest population in both the years.
Keywords: Population dynamics, abiotic factors, Cydia ptychora, pigeonpea, Manipur