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| Author: | S. Gazit |
Abstract:
In the early 1970s it was found in Israel that ‘fertigation’ throughout the dry season (April to November) insures good vegetative development of young litchi plants.
Planting of about 150 ha commercial orchards ensued in the late 70s.
However, when these orchards came into production the yield was very disappointing, averaging only 3 - 4 ton/ha.
Research on litchi productivity in Israel had started in 1969. Two M.Sc. theses increased greatly our understanding of the litchi productive biology and its response to auxin spraying; albeit, no practical solution was found for the problem of poor productivity.
Only, a decade long comprehensive research, starting in 1988, succeeded in elucidating the factors responsible for poor litchi productivity and developing techniques to increase significantly yields, to 10-20 ton/ha.
Two main techniques are being used in most commercial orchards: a.
Autumnal water stress - to induce profuse flowering. b.
Auxins sprays, applied several weeks after fruit set – to prevent excessive fruitlet drop and increase fruit size.
We estimate that under optimal growing conditions an average litchi yield of 20 ton/ha can be obtained.
Factors that may limit such a yield are: deficiency of normal female flowers and/or inadequate pollination with fully viable pollen.
Some cultivars may also require pollination with foreign pollen to reach their full yield potential.
The challenge we face in the present decade is to realize this potential with most high quality cultivars.
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