IN VITRO REGENERATION OF CHENIN BLANC AND CANONANNON VARIETIES OF GRAPEVINE (Vitis vinifera L.) FROM LEAF EXPLANTS

Grapevine (Vitis vinifera L.) is one of the most widely distributed fruit crops in the world. The availability of adequate amount of quality and disease free planting materials within a short time is the major limiting factor to attain large scale grapevine production using the conventional method of Propagation. Therefore, development of an optimal in vitro propagation technique is too much needed. The objective of this study was to develop an optimal in vitro regeneration protocol for two grapevine varieties (Chenin blanc and Canonannon) from leaf explants. The leaf explants have been cultured on MS basal medium prepared with (0mg/l, 1mg/l, 1.5mg/l, 2mg/l, 2.5mg/l, 3mg/l and 4mg/l) BAP and (0mg/l, 0.1mg/l, 1mg/l, 2mg/l, 2.5mg/l and 3mg/l) TDZ separately for shoot induction and multiplication. One-month sub cultured shoots of the grape varieties were rooted on the full strength 20ml MS medium supplemented with 3% (w/v) sucrose and with different concentrations of IBA (1mg/l, 2mg/l, 3mg/l and 4mg/l) and IAA (2mg/l and 4mg/l) and the plantlets were then transferred to 12cm diameter plastic bag containing sterilized red soil, sand and cow dung manure at the ratio of 1:2:1, respectively for acclimatization. From the tested seven different concentrations of BAP and six different concentrations of TDZ, the best direct shoot regeneration was obtained at 2mg/l BAP for both Chenin blanc (2.6±0.5) and Canonannon (2.3±0.2). Therefore, frequency of shoot regeneration was greatly influenced by the concentrations of growth regulators. Efficient rooting of in vitro regenerated plants and subsequent establishment was achieved on a medium supplemented with 2mg/l IBA for both varieties of grapevines. The survival rates were 75.0% and 83.3% for Chenin blanc and Canonannon, respectively. It is necessary to investigate the indirect shoot regeneration mechanism for both varieties at higher concentrations of the growth regulators that were not included in this study