不结球白菜游离小孢子培养及植株再生研究

Isolated Microspore Culture and Microspore-derived PlantRegeneration in Non-heading Chinese Cabbage

为进一步优化不结球白菜游离小孢子培养技术体系,本研究以20个不同基因型的不结球白菜为试验材料,研究不同基因型、4℃低温胁迫处理时间和头孢噻胯浓度对游离小孢子胚胎发生的影响,并对小孢子胚胎发育和再生过程进行观察和倍性鉴定。结果表明,当花瓣/花药(P/A)长度比值为0.85～1.10时,不结球白菜小孢子主要处于单核晚期;共有10个基因型不结球白菜出胚,其中出胚率最大的为H20,平均出胚率为7.75胚·10蕾^(-1);4℃低温胁迫处理1 d时不结球白菜出胚率最高;头孢噻胯对不结球白菜出胚率的影响与基因型密切相关;从胚状体到再生幼苗阶段,不结球白菜基因型不同,其胚胎再生频率也不同;倍性鉴定共检测出21个双单倍体和2个单倍体,自然加倍率为91.3%,不结球白菜植株形态表现出明显的多样性。本研究结果为不结球白菜游离小孢子高效培养体系的优化提供了一定的技术支撑。

In order to optimize the microspore culture technology in non-heading Chinese cabbage, the effects of genotype, low temperature stress and the addition amount of cefotaxime on the embryogenesis of isolated microspore were studied with 20 genotypes of non-heading Chinese cabbage. The development of microspore-derived embryos, the embyros regeneration and the ploidy identification were also observed, The results were as follows: When petal/anther(P/A) was 0.85~1.10, the microspores of non-heading Chinese cabbage were mainly in the late stage of uninucleate. There were 10 genotypes of non-heading Chinese cabbage showing embryogenesis, the incidence of embryo was highest for the genotype of H20, which was 7.75 embryoids·10 bud-1. Low tempeature stress pretreatment at 4℃ for 1 d was helpful for embryogenesis. The effect of cefotaxime on the rate of embryo formation was highly dependent on genotype. From the embryoids to seedling stage, the frequency of embryo regeneration was varied within different genotypes;21 microspore-derived plants were doubled haploids(DH) and 2 were haploids through ploidy identification, the natural doubling rate was 91.3%. The morphology of the obtained microspore-derived plants showed obvious diversity. These researches provide a way for the optimization of microspore culture in non-heading Chinese cabbage.