Assessing the photo-assimilate ( 14 C) partitioning dynamics between the source and the sink to decipher an efficient pruning practice in guava (Psidium guajava L.)

Radiotracer ( ¹⁴ C) experiments were conducted to develop a sustainable pruning strategy in guava ( Psidium guajava L.) based on the source-sink carbon partitioning ( ¹⁴ C) dynamics. ¹⁴ C-photoassimilate transfer from the source leaves followed the following scheme based on the respective sink’s demand i.e. fruit on the source leaf branch > shoot and foliage of the source leaf branch > fruit on the adjacent branch > shoot and foliage of the adjacent branch. This study clearly indicates that the source leaves adjacent to the developing fruit play a crucial role in governing the fruit growth and development. Thus, for an efficient canopy management and for a sustainable year to year productivity, instead of pruning an overall outer canopy, the pruning strategy in guava can be so designed to remove the branches on which the fruits are not desired, leaving intact the branches targeted to bear the fruits.