Tree size control in mango (Mangifera indica L.) - some considerations.
Iyer C. P. A., Kurian R. M.
Author Affiliation: IIHR, Hessarghatta, Bangalore 560?089, India.
: 425-436
Abstract : In order to achieve more consistent tree growth control, 3 approaches are considered to be the most promising: (1) breeding dwarfing rootstocks, (2) chemical control and (3) developing new polyembryonic rootstocks. In studies of morphological, physiological, anatomical and biochemical characteristics of trees of various cultivars, higher phenolic levels and a higher xylem:phloem ratio were shown to be associated with dwarfing and thus could be used as criteria for pre-selection screening. Additionally, the percentage of shoots giving rise to new flushes and the duration of flushing were correlated with tree size and vigour. In field trials with cv. Alphonso, soil drenching with paclobutrazol at 2.5 g/tree during Nov. and Mar. in alternate years reduced tree vigour by about 50% compared with the control. Paclobutrazol treatments enhanced the total phenolic content of apical buds, increased xylem:phloem ratios in the stem and reduced endogenous abscisic acid and active cytokinin levels.