Improvement of Plant Regeneration Frequency from Carbon Sources in Aromatic Rice (Oryza sativa L.)

Abstract

The objective of this research is to investigate carbon sources for optimum callus induction and plant regeneration frequencies. The effect of carbon sources on callus induction and plant regeneration from mature seeds of aromatic rice (Oryza sativa L.) cultivar Khao Dawk Mali 105 (KDML105) was studied in this experiment. For callus induction, the different types of carbon sources along with 30 g L−1 of sucrose or maltose were evaluated. NSI and NMI medium were used for callus induction in three replicates (sucrose and maltose as carbon sources, respectively). The calli derived from NMI medium showed the higher percentage of callus induction, fresh weight, dry weights, callus size, green spots and regeneration frequency than calli derived from NSI medium. For plant regeneration, the 3-week-old calli were transferred to the regeneration medium which was different in carbon sources (NSR, NMR, NSMR0.5, NMMR0.5, NSMR1, NMMR1, NSMR1.5, NMMR1.5, NSMR2, NMMR2, NSMR2.5 and NMMR2.5 medium) and tested to investigate the effect of carbon sources in three replicates. The percentage of regeneration (60.71%) and the ratio of the number of seedlings to the number of regenerated calli (3.02) obtained from NMR medium showed the highest values. The percentage of callus induction and morphological performance (weight and size) were correlated with plant regeneration frequency. The results showed that using maltose as a carbon source gave a better result than using sucrose as a carbon source for callus induction and plant regeneration in aromatic rice cultivar KDML105. The regenerated plants were successfully rooted and well grown in greenhouse conditions.