Effects of L-lysine on Callus Formation , Plant Regeneration and Flowering of Thai Rice c.v. KDML 105

Abstract

Seed-cultured of KDML 105 on Murashige and Skoog (MS) medium supplemented with 2 mg/l 2,4–D , 1 g/l L-proline , 1 g/l casein hydrolysate and 20 μM L-lysine produced the highest average percentage of callus formation (95.16%). Regeneration of the calli into plantlets could be best achieved at the average of 63.87 % in the MS medium containing 1 mg/l kinetin, 1 g/l L–proline, 300 mg/l casein hydrolysate and 20 μM L-lysine. Plantlets were cultured in the MS medium containing 3 mg/l BAP, 3 g/l activated charcoal and 20 μM L-lysine before transferring to pots under greenhouse condition. Two plants out of 80 plantlets reached the flowering stage under long photoperiod and produced only 6 seeds altogether. The seeds were subsequently planted for 2 generations and DNA fingerprints of these plants were determined using sequence related amplified polymorphism (SRAP) technique. All 6 clones of the L-lysine-treated plants gave different DNA patterns from that of the original KDML105 suggesting some effects of L-lysine on their genetic variation.