Alleviation of shoot tip necrosis in in vitro propagation of Salvia santolinifolia, Boiss

Shoots of Salvia santolinifolia can be regenerated and multiplied on MS medium containing 3.0 mg/l of BA. Shoot tip necrosis has been noticed to be the main preventive factor in in vitro shoots regeneration. The necrosis of shoots appeared with the yellowing of top leaves following bum of leaf and finally death of whole shoots. The intensity of shoots tip necrosis were found more in elongated shoots (5-7 cm) whereas shoots less than 5-7 cm the frequency of shoots tip necrosis were low. Various factors such as strength of the media, charcoal and different combination of nutrients have been investigated for reducing the occurrence of shoot necrosis. Shoots tip necrosis can be reduced (0-10 %) by increasing the level of calcium in combination with increased concentrations of Magnesium (Mg) Manganese (Mn) and Iron (Fe) of MS medium containing 3.0 mg/l of BA. Apart from calcium, subculture interval also reduced shoot tip necrosis still at low level. Transfer of shoots showing easily signs of necrosis to half strength MS medium supplemented with BA (3.0 mg/l). All the additive including Activity charcoal promoted shoot tip necrosis and inhibited shoots multiplication.