Effect of sucrose on calus induction and green plantlet regeneration in anther culture of Indica x Indica rice

Abstract

Anther culture is an important biotechnological tool. By rice anther culture homozygous pure lines in the form of doubled haploid (DH) plants can be produced within a year as compared to the long inbreeding method, which might take 8-10 years. Application of anther culture technique in breeding and genetics research is limited due to the very low regeneration frequency of anthers of rice in general, and indica cultivars in particular. Therefore, the successful use of the technique depends on the adequate production of DH plants for selection and field evaluation. Effect of various concentrations of sucrose in callus induction media was investigated on callus induction and regeneration of green plantlets from anther culture of several F1s derived from indica x indica crosses. Cold pretreated anthers of five genotype of anther donor plants (F1s) at 5 °C for 8 days were cultured on N6 callus induction medium containing sucrose at a concentration of 6.0%, 6.5%, and 7.0%. Results revealed that all genotypes showed similar response to callus induction, but a significantly different responses to plant regeneration depended on sucrose level in the callus induction media. Two genotypes, i.e. IR78788 / Inpara 5 and Dendang/Inpari 30 only regenerated albino plantlets. In this experiment, 6.5% sucrose compared to two other sucrose treatments was suitable for inducing high frequency callus induction and high green plant regeneration in all genotypes. The high concentration of sucrose (7.0%) in the culture medium not only resulted in a decrease in the number and percentage of callus formation but also decreased the regeneration of green plantlets.