ANTHER CULTURE PERFORMANCES OF SELECTED Indica RICE VARIETIES IN SRI LANKA: ABILITY OF CALLUS INDUCTION AND PLANT REGENERATION

Abstract

Doubled-haploid plant production through anther culture provides an efficient and appropriate system for rapid production of homozygous lines. Various culture conditions influence callus induction and plant regeneration efficiency. In this study, the optimization of media requirements and culture conditions for high-frequency callus induction and plant regeneration for selected indica rice varieties were evaluated using improved anther culture media. Panicles of ten selected rice cultivars (Bg 358, Bg 379-2, Bw 361, At 362, Bw, 364, Bw267-3, Bw 272-6b, At 306, Bg 357 and Kahata wee) were cold pre-treated at 10ºC for 7-10 days. After that anthers were cultured in agar solidified N6 and L8 media where hormonal combinations were modified. Calli were transferred to three different Murasinge and Skoog media for plant regeneration. Green and Albino shoots were observed. Best callus induction frequencies (6.9-11.1%) were acquired in the L8 medium containing 6% (w/v) maltose, over the N6 (3.6—5.7%) medium. Highly responsive genotypes for callus initiation were AT362, BG 379-2, BW 267-3 and AT 306. BG357 and BW 364 were the least responsive genotypes. The best callus induction frequency of 11.1% was observed in the L8 medium supplemented with 2.0mgl-1 2, 4-D and 0.5mgl-1Kinetin (KN) for AT 362. Maximum green plant regeneration could be observed in Kahata wee (29.2%) and AT362 (18.27%) varieties in MS media supplemented with 2mg/l BAP, 1mg/l NAA and 0.5mg/l KN. After 7-10days of callus initiation, they were transferred to MS medium to regenerate plants. Plant regeneration was observed after two weeks after the transfer. This information could be used in the development of homozygous plants with high yields and good grain quality from the best hybrid varieties.