Potential Use of Partial Desiccation Treatment for Regeneration System of Malaysian Indica Rice (O. Sativa L.)

The present study shows that callus induction varied among the MR220 and MR232 cultivars tested and the response to 2,4-dichlorophenoxyacetic acid (2,4-D) was low. The highest percentage of callus induction for MR232 was 41% and 37% for MR220 cultivar. The morphology of embryogenic callus for both cultivars was dry, compact, and light yellowish. Partial desiccation treatment applied to improve plant regeneration of rice callus cultivars. Embryogenic rice callus was exposed to different desiccation periods (24 hours, 48 hours and 72 hours) and its effect was evaluated in terms of frequency of regeneration. The optimal desiccation period (72 hours) in MR232 callus enhanced plant regeneration response up to fivefold and twofold in MR220 rice cultivar (48 hours) compare to undesiccated control. The study suggests that partial desiccation treatment can be useful in stimulating regeneration response in indica rice particularly for Malaysian rice.