杂交籼稻亲本成熟胚组培研究

Studies on Enhancement of Tissue-culture Efficiency in Mature Embryo of Parental Lines of Indica Hybrid Rice

由于水稻组培效率对基因型的依赖性较强,因此针对水稻基因型研究和建立其高效组培技术体系尤为重要。筛选了愈伤诱导基本培养基,比较了6-BA和Kt对植株分化的效果,优化了激素配比。结果表明:16个基因型在愈伤诱导培养基MS上,平均愈伤诱导率和胚性愈伤诱导率分别为83.47%、38.59%,较CC培养基分别高出3.40%和7.42%;16个基因型中有12个基因型在MS培养基中表现出更高的胚性愈伤诱导率,且出愈时间早、愈伤生长快,不易褐化,说明MS培养基可作为杂交籼稻亲本成熟胚愈伤诱导的广谱培养基;植株分化预备试验结果显示,6个基因型在附加6-BA的分化培养基中均表现出更高的绿苗分化率,平均较使用Kt提高了10.65%,说明6-BA较Kt用于植株分化可取得更好效果;正交试验优化植株分化激素配比的试验结果表明R998和R463的最优激素组合均为3 mg/L 6-BA+0.5 mg/L NAA+1 mg/L Kt,而R253和R402的最优激素组合分别为1 mg/L 6-BA+1 mg/L NAA2、mg/L 6-BA+0.5 mg/L Kt,说明通过优化分化培养基中的激素配比,可以进一步提高了籼稻绿苗分化率,尤其是对于植株再生培养力低的基因型极为有效。

Tissue culture efficiency of rice was highly dependent on the genotypes. It was of great paramount to study and set up an efficient tissue culture system focused on the particular genotypes of rice. The research screened more suitable callus induction medium, compared the effectiveness of 6-BA and Kt in the plant regeneration, and optimized the combinatiom and concentrations of plant growth hormones in plant regeneration medium. The results showed that the average CIR and ECIR obtained on MS medium were 83.47% and 38.59%, respectively, being 3.4% and 7.42% higher than on CC medium, and among the 16 tested genotypes, 12 had sirmdtaueously higher CIR and ECIR on MS than on CC. In addition, earlier response and more rapid growth of ealli with lower rate of necrosis were observed on MS. Therefore, it indicated that MS medium had a broader spectrum in terms of callus induction from mature embryos of the indica hybrid rice parental lines. Comparison of the effectiveness of 6-BA and Kt showed that all of the 6 tested resterer lines displayed a higher GPRR on the medium consisting of 6-BA than that of Kt, and on average, the GPRR was 10.65% higher compared to the use of Kt. Hence, it was preliminarily concluded that 6-BA had a better effectiveness than Kt for plant regeneration in indiea hybrid rice. The orthogonal test showed that the optimal cembination and cencentmtion of hormones for 2 genotypes, such as R998 and R463, were 3 mg/L 6-BA ＋ 0.5 mg/L NAA ＋ 1 mg/L Kt, while the optimal combination and concentration of hormones for R253 and R402 were 1 mg/L 6-BA ＋ 1 mg/L NAA and 2 mg/L 6-BA ＋ 0.5 mg/L Kt, respectively. In general, the orthogonal test with the hormones obtained very significant results in increasing the green plant regeneration rotes of rice genotypes. Therefore, it was indicated that optimization of combinations and concentrations of honnones could further increase the GPRR of indica genotypes, especially, of those recalcitrant genotypes of indica rice.