Regulation of bearing potential for sustainable production and quality improvement of litchi in Indian subcontinent
Litchi (Litchi chinensis Sonn.) is a fascinating fruit liked by people due to its unique flavor and reddish peel. Fruit has high demand not only on the domestic market but also in the global market and thus has immense export potential. Litchi fruit production depends on many factors like proper orchard management including nutrition, irrigation, canopy architecture, etc., but the returns from orchards directly depend on the bearing and the quality of the fruit harvest. Nowadays in India existing litchi cultivars have more or less tendency of alternate bearing and this is a major problem of sustainability of production and market regulation. On and off bearing of trees directly hampers the economy of litchi growers and moreover in the changing climatic condition this problem is increasing day by day. Recently new areas have come up in litchi and many orchards trees are in the non-bearing young litchi stage which is characterized by its vigorous root growth, on which the further top growth is based, hence, the sink strength of the root system must be stronger than that of other organs, being at variance with bearing mature trees. In order to sustain the production, there is need for effective technological intervention by which the production for litchi growers is ensured. We analysed in India a number of factors like lack of proper canopy management, delay in application of manures and fertilizer, incorrect dose of nutrition, lack in proper plant health management and particularly in management of leaf defoliators apart from changing climatic conditions are associated for regulating the bearing which may one or in other way be responsible for bearing which are as which force the plant to flush in irregular manner. All these factors affect shoot maturity and cause failure to bloom. To combat the irregular bearing problem in the Indian subcontinent, there is a need to focus on the essential practices followed for the regulation of tree's vegetative and reproductive growth by physical and chemical means. The patterns of source-sink relationship were modified by girdling in favour of the fruits, which changed from weak to stronger in the competition of assimilates and/or hormones with other sinks. Some progress in studying the flower differentiation has been made; yet, many unsolved problems still exist. Spiral and closed girdling of primary branches, are practiced to promote flower development and fruit set. Judicious use of growth regulators is to be applied to discourage winter flushing in favour of flower initiation, to prevent excessive fruit drop and lessen fruit cracking.
Kumar, A., Singh, S.K., Pandey, S.D., Patel, R.K., Srivastava, K. and Nath, V. (2020). Regulation of bearing potential for sustainable production and quality improvement of litchi in Indian subcontinent. Acta Hortic. 1293, 41-46
biochemical parameters, flowering, girdling, litchi, primary branches, regulation