PREDICTING CROP YIELD AND YIELD COMPONENTS OF SPRAY CHRYSANTHEMUM (CHRYSANTHEMUM MORIFOLIUM RAMAT) IN RELATION TO WEATHER VARIABLES
Fifteen cultivars of spray chrysanthemum were planted in a greenhouse and open field conditions separately under 3 planting dates of mid-July, late-July and mid-August to assess the degree of influence of direct and derived weather variables on floral characters and growing period of spray chrysanthemum and also to predict the yield component from weather variables. Maximum and minimum temperatures were recorded and several thermal indices were developed. Correlation coefficients were studied to obtain the degree of association between temperature variables and crop characters at harvest. Finally, regression equations were developed to obtain a quantitative estimate of these crop parameters as a function of various temperature variables. Results indicated that during planting to flower bud emergence (FBE) phase the effect of night-time temperature in correlations with floral and stem characters was always more pronounced (r=0.88 to 0.94) than daytime temperature (r=0.1 to 0.88). During planting to FBE, and FBE to flowering stage it was observed that increases in air temperature increased the duration of each phenophase. The curvilinear equations showed that 83-94% of the variability of yield components was due to night temperature. The two variables, night temperature and growing degree days together explained 79-86% of variability in flower weight and flower size.
Gantait, S.S., Pal , P. and Saha, A. (2012). PREDICTING CROP YIELD AND YIELD COMPONENTS OF SPRAY CHRYSANTHEMUM (CHRYSANTHEMUM MORIFOLIUM RAMAT) IN RELATION TO WEATHER VARIABLES. Acta Hortic. 937, 321-328