Paddy stem-borer (Tryporyza Incertulas Walker) infestation is very much influenced by meteorological factors. The effect of various weather elements on its incidence is endeavoured in present statistical analysis. It is found that less moisture content in the atmosphere in the elongation stage and a minimum temperature lower than 23 deg. C and sunshine hours more than 8 hours in flowering stage are favourable for increased larval activity in the earing stage of summer paddy crop at Bhubaneshwar. Northeast region of India are prone to heavy attack in summer and winter crops earing stage. Similar studies for other stations are necessary to draw general conclusion about threshold values of meteorological parameters to be used in forewarning of the infestation of stem-borer in paddy.

The possible linkage between different meteorological elements and a few pests of jowar,  like stem-borer, earhead bug and mite. based on the statistical analysis of the past 7 to 13 years records is derived in this study. Data of kharif jowar crops at Dharwar and Coimbatore is utilized. The simple and multiple linear regression techniques are adopted. It is found that higher maximum temperature. minimum temperature >13°C and relative humidity >70% during November-December are favorable for stem-borer attacks: The optimum miximum temperature of 28°C in November and 31°C in August are obtained for earhead bugs incidences. Their activities are suddenly decreased at minimum temperature > 17°C in December at Coimbatore but increases when it is > 18°C during October at, Dharwar. Jowar mites show enhancements In activity with Increase In maximum temperature (30 C) during July higher minimum temperature (20°C) during November, sunshine hours of greater than 7 in July and a weekly rainfall of 80-90 mm during last week of September at Coimbatore. After corroborating with the actual observations, these results may be useful in essuing forewarnings of, the incidences of these pests on jowar .