In vitro propagation of Persea indica

Persea indica is very susceptible to Phytophthora cinnamomi and is a useful plant in research on avocado root rot. P. indica is not indigenous to South Africa and seed is unobtainable. For root rot research, plants which are produced vegetatively have considerable advantages over seedlings because genetic variations are reduced. This paper reports on the successful in vitro propagation of P. indica. Materials and Methods Shoots (3 to 5 cm) were taken from one year old P. indica seedlings growing in the greenhouse. Shoots were sterilized for 15 minutes in a 1 % sodium hypochlorite solution to which Tween was added as a wetting agent. This was followed by two successive rinses in sterile distilled water. Each shoot was then cut into a tip cutting (5 mm) and one or two one-node cuttings, depending on the length of the shoot. Cuttings were placed on a modified Murashige and Skoog (1962) medium (MS). The basal medium (BM) contained the following major elements half strength (MS), minor elements- full strength (MS), FeNaEDTA (25 mg/l), sucrose (30 g/l), myo-inositol (100 mg/l), NaH2PO42H20 (170 mg/l), adenine sulphate (80 mg/l), ascorbic acid (25 mgA)