author(s)
I Merlin Kamala and JS Kennedy

abstract
A study was conducted to assess the population dynamics of jasmine leaf webworm in jasmine ecosystem in two different climate zone ie Madurai and Coimbatore District of Tamil Nadu. It was evident from the study that the occurrence of jasmine leaf webworm, Nausinoe geometralis was less severe during December and January and the leaf web worm density varied from 14.62 and 19.65 percent in Madurai District, while the incidence was minimum from December till February in Coimbatore district with the population varying from 12.75-19.42 percent. The leaf webworm population was found to increase steadily in summer months in both the districts, slightly declined in the month of June due to showers of rainfall and then the incidence rebound. The peak incidence was noticed in the months of September, October and November in both the investigated districts. From the present investigation it is evident that the jasmine leaf webworm population in jasmine had a significant positive correlation with maximum temperature, (r = +0.395) and (r=+0.304) and negatively for relative humidity (r=-294) and (r= -0.338) and rainfall (r= -0.368) and (r=-0.334) in Madurai and Coimbatore districts respectively. A significant positive correlation was recorded for sunshine hours and wind velocity on both the investigated districts.