a1 Plant Physiology Section, Central Plantation Crops Research Institute, Regional Station, Vittal·514: 243, India
The variation in setting fruit and immature fruit abscission at successive nodes of an individual panicle, and in panicles at different directions of the canopy in an individual tree, were studied in cashew (Anacardium occidentale L.). The numbers of perfect flowers and fruits set increased from the proximal to the distal end with the maximum yield at the fifth or sixth nodes in a panicle of 8–10 branches. The productivity of an entire inflorescence or a whole fruiting branch was related to its orientation with respect to the sun. The numbers of nodes and fruits set and the percentage of fruit retained were maximal in panicles located on the western and southern sides of the canopy. Tea mosquito damage was also less on these sides of the canopy but the physiological disorder of ‘apple’ cracking was higher here than on the eastern and northern sides. These variations are discussed in relation to the differences in the incident photosynthetically active radiation on these sides.
(Received August 31 1982)