AN EFFICIENT IN-VITRO REGENERATION SYSTEM FOR AUSTRALIAN-GROWN CHICKPEA (CICER-ARIETINUM) CULTIVARS

A comparison of methods for efficient in vitro regeneration of Austral ian-grown chickpea (Cicer arietinum L.) cultivars was undertaken. The most efficient regeneration system was one where immature cotyledon an d embryonic axis explants, 14-21 days post-pollination, were cultivate d on Murashige and Skoog's salts with Gamborg's vitamins, 1.0, 3.0 or 5.2 mg L(-1) zeatin, 0 or 35 mu g L-l indole-3-acetic acid, 30 g L(-1) sucrose and 8 g L(-1) Phytagar. The first embryoid structures appeare d after 2 weeks of culture at 25 +/- 1 degrees C in dim light (150 mu mol m(-2) s(-1)) and formed directly on the edges of the immature coty ledons or petiole stumps. Between 10 and 20 structures were produced o n each cotyledon explant in two cultivars, however, the embryogenic st ructures which developed on cv. Narayen were more efficiently transfor med into shoots than far cv. Amethyst. An efficient regeneration mediu m (2 mg L(-1) naphthaleneacetic acid, 1/2 Murashige and Skoog's salts with Gamborg's vitamins, and 0.5 g L(-1) activated charcoal) was used to develop a portion of the shoots into morphologically normal plants growing in a vermiculite and soil potting mix in a growth room. Less e fficient in vitro regeneration was observed when hypocotyl and shoot s ections, and shoot apices were induced to form callus and plants by or ganogenesis. These plants could not be established in a potting mix. T he amount and type of callus produced varied between explant type and cultivar.