There are two distinct groups of commercial mango (Mangifera indica L.) cultivars with regard to flowering behaviour. One group flowers in alternate years while another group flower and fruit every year. However, there is diversity in flowering ability among the potentially productive branches of both types of mango trees. Significant variations in net photosynthetic rate (PN), transpiration rate, stomatal resistant, stomatal conductance, dark respiration and mesophyll efficiency (mesophyll capacity to fix CO2) were observed among these productive branches. The extent of variation was more pronounced in cvs. Chausa, Dashehari and Langra (irregular bearing), while cvs. Amrapali, Banglora and Neelam (regular bearing) showed less variation. Correlation coefficient and principal component analysis indicated that variation in flowering intensity among the branches were mainly due to the wide variation in stomatal conductance and photosynthetic rate which resulted in variation in their mesophyll efficiency. In case of regular bearing trees, the narrow range of variation in PN may be related to a better mesophyll capacity. This in turn might result in higher carbon build-up in terminal potential branches which would have helped them to flower regularly with minimum branch to branch variations. These varieties were grouped in to two different cluster using cluster analysis. Regular bearing cultivars formed cluster 1 while irregular one formed cluster II.
Diversity, Flowering, Mango
