International Journal of Farm Sciences

The present investigations were done to evaluate the weather parameters with correlation and regression analysis of the yellow sigatoka leaf spot in banana plantation at four locations viz Erasakkanayakkanur, Seepalakottai, TNAU orchard and Vellaiyankadu. In Erasakkanayakanur the relative humidity (0.611) and rainfall (0.622) were positively significantly correlated; maximum temperature (−0.608) was negatively correlated with respect to the sigatoka leaf spot in banana. All the three parameters were significantly correlated with the disease incidence. In Seepalakottai relative humidity (0.710) and rainfall (0.687) were significantly correlated with incidence of banana sigatoka leaf spot and at TNAU orchard the independent variables viz maximum temperature (−0.619) and minimum temperature (−0.573) were negatively correlated whereas relative humidity (0.862) had highly positive significant correlation with the disease. In velliangadu relative humidity (0.547) and rainfall (0.607) were positively correlated with the disease incidence although maximum and minimum temperatures had negative correlation and were statistically insignificant. At all locations relative humidity was positively correlated with disease incidence followed by rainfall. In regression, models to predict the rate of disease increase were developed in several stages. In the first stage each dependent variable was regressed on 4 environmental variables like maximum and minimum temperature, relative humidity and rainfall for one host variable. The R² values of the best equations were used as guide to indicate the levels of precision that could be attained for any given dependent variable. More appropriate statistics for that purpose were used at later stages of the analysis. The R² values ranged from 0.39, 0.51, 0.74 and 0.37 at four locations viz Erassakkanayakkanur, Seepalakottai, TNAU orchard and Vellaiyankadu respectively.