Abstract
The purpose of this study is to improve the culturability of a indica type rice cultivar, IR 36, using DNA marker associated with the ability of plant regeneration in anther and seed culture. The varietal difference of ability of callus formation and plant regeneration was investigated in anther and seed culture of 8 rice cultivars. Three japonica rice cultivars showed to have better culturability than those of tongil and indica type genotypes. But two indica/japonica lines, 'MGRI 079' and 'MGRI 036', which were selected to have good culturability in previous study showed the highest regenerability (20%) in anther culture of 8 rice cultivars. Thirty four $BC_2F_4$ lines were selected by marker screening using RZ400 for 100 $BC_2F_4$ lines derived from a cross $'MGRI\;079/IR\;36^{^*3}'$. The frequency of callus formation of 30 $BC_2F_4$ lines was higher than those of 'IR 36' in anther culture of the selected $BC_2F_4$ lines. The ability of plant regeneration of 15 lines was higher than that of 'IR 36' in the seed culture of 34 $BC_2F_4$ lines. A promising line, $BC_2F_4-28$, was selected to have better culturability in the anther and seed culture of the $BC_2F_4$ lines. The heading date and grain shape of the $BC_2F_4-28$ was similar to 'IR 36'. In seed culture of 50 $BC_4F_3$ lines derived from a rice cross $'MGRI\;079/IR\;36^{^*5}'$, 11 lines including $BC_4F_3-3$ showed to have higher regenerability compared with 'IR 36'. The highest frequency of plant regeneration (11%) was obtained from $BC_4F_3-46$ in seed culture of the $BC_4F_3$ lines.
벼의 약 및 현미 배양효율과 관련된 DNA marker를 이용하여 인디카형 벼 품종인 'IR 36'의 조직배양 효율을 개선하기 위하여 실험한 결과를 요약하면 다음과 같다. MGRI집단의 약배양에서 식물체분화율이 높은 계통으로 선발된 'MGRI 079'와 'MGRI 036'의 약배양 효율은 각각 19.8%, 19.9%로 가장 높게 나타났다. 'MGRI 079'에 'IR 36'이 여교배되어 양성된 $BC_2F_4$ 100 계통에 대한 marker 검정을 실시하여 선발된 34 계통중 약배양에서 캘러스 형성률이 'IR 36'보다 높은 계통은 30계통이었고, 현미배양에서 'IR 36'보다 식물체 분화율이 높은 계통은 $BC_2F_4-28$ 외 14 계통이었다. $BC_2F_4$ 34계통 중에서 식물체분화능력이 높은 계통으로 선발된 $BC_2F_4-28$은 간장이 'IR 36'보다 큰 편이었으나 출수기와 미립특성은 'IR 36'과 비슷하였다. 'MGRI 036'에 'IR 36'을 반복친으로 여교배하여 양성된 $BC_4F_3$ 50계통의 현미배양을 실시한 결과 'IR 36'보다 식물체 재분화율이 높은 계통은 $BC_4F_3-3$ 외 10 계통이었고, 그중 $BC_4F_3-46$의 식물체 재분화율이 11%로 가장 높게 나타났다.
