Plant Regeneration from Embryo Derived Callus of Aromatic Rice (Oryza sativa L.) Variety Khao Dawk Mali 105

Abstract

Effects of growth regulators, organic substances and some factors on callus induction and plant regeneration from embryos of aromatic rice (Oryza sativa L.) variety Khao Dawk Mali 105 were studied. It was found that embryos cultured on Murashige and Skoog (MS) agar medium supplemented with 2 mg/l 2,4-dichlorophenoxyacetic acid and 300 mg/l casein hydrolysate under light condition produced the high percentage of callus formation (96.3%). The average size of callus produced was largest (9.4 mm). The calli dehydrated by placing in petridishes with covers for 7 days before transferring to regenerating medium produced higher frequency of shoot regeneration than calli cultured on regenerating medium without dehydration. There were 2 kinds of the suitable media for plant regeneration. One medium was MS agar medium supplemented with 1 mgl indoleacetic acid (IAA) and 4 mg/l benzyladenine (BA) which induced the highest percentage of calli forming shoots (45.8%) and each callus produced shoots average 7.9 shoots. Another medium was MS agar medium supplemented with 1 mg/l IAA, 4 mg/l BA and 1 g/l yeast extract which induced the high percentage of calli forming shoots (45.5%) and each callus produced the highest number of shoots (average 8.7 shoots).