- J H Ooshuizen1, D J Roe1 & C M Menzel2
-
1Institute for Tropical and Subtropical Crops, Private Bag X11208, Nelspruit 1200, South Africa
2Maroochy Horiticulture Research Station, Queensland Department of Primary Industries,
PO Box 5083, SCMC, Nambour, Qld 4560 Australia - 1994
The effects of drought stress on 10-year-old Mauritius litchi trees growing on a sandy loam soil at Nelspruit in subtropical South Africa (lat 25° S), were investigated over a single season to develop irrigation strategies for this crop. Trees were watered weekly to replace transpiration (wet), or dried out slowly from soon after panicle emergence in late July until after harvest in January (dry). Volumetric soil moisture was measured weekly to 150 cm soil depth with a neutron probe. The range in tree moisture status was monitored by measuring leaf water potential on the shaded side of the tree at 09:00 and on the exposed side of the tree at 14:00. Net photosynthesis was also measured at 09:00 on the exposed side of the tree. The growth of floral panicles and leafy shoots was measured before anthesis (flower opening), and the number and weight of fruit and its components after fruit-set.