방사선을 이용한 내염성 계통의 기내선발 및 특징

Abstract

1.5% NaCl이 함유된 배지에 캘러스를 치상하여 방사선을 처리한 결과 무처리구보다 처리구 (30, 50 Gy)에서 캘러스 생존율 및 재분화율이 증가하여 내염성 캘러스를 선발하는데 방사선의 적용이 효과적임을 알 수 있었고, 내염성 캘러스에서 재분화된 M<TEX>$_3$</TEX>세대 종자에서 내염성 계통들은 모품종보다 초장, 근장 및 근수의 생육이 우수하여 이러한 계통은 내염성 연구를 위한 유용한 유전자원으로 이용할 수 있을 것으로 생각된다. 또한 RAPD 기술은 대조구와 내염성 캘러스에서 재분화된 계통을 구분하는데 유용한 기술임을 알 수 있었다. The combination of radiation technique with an in vitro culture system was initiated to develop salt tolerant rice. We established an in vitro culture system to select tolerant lines against salt stress. NaCl tolerant cell lines were selected from the callus irradiated with gamma ray on N<TEX>$_{6}$</TEX> medium with 1.5% NaCl and 2 mg/L 2,4-D. Regenerants (M<TEX>$_1$</TEX>) were obtained from the tolerant callus which was cultured for 30 days auxin-free medium. The M<TEX>$_2$</TEX>seeds were harvested from M<TEX>$_1$</TEX>plants on an individual plant basis. Thirty seedlings from each 450 M<TEX>$_2$</TEX>lines were transplanted in a field and total 5,000 M<TEX>$_3$</TEX>lines were harvested with an average 90 percent of fertile grain. M<TEX>$_3$</TEX>lines were utilized for selection of salt tolerance. Salinity-tolerant lines (225) were selected among 5,000 M<TEX>$_3$</TEX>lines. Of the 225 lines tested, the morphological traits of two lines (120-10 and -11) were far superior to control (Donagjinbyeo) in agromomic traits such as plant height, root length and no. of roots. Control and tolerant lines were analyzed by RAPD markers. Three polymorphic bands were presented in only tolerant lines, demonstrating a genetic difference between control and the tolerant lines. Such tolerant lines could be used as genetic resources to improve salt tolerance.e.