摘要
以甜瓜属人工异源四倍体(Cucumis×hytivusChenandKirkbride,2n=38)与华南和华北两种生态型栽培黄瓜(C.sativusL.,2n=14)进行杂交,比较各个杂交组合的坐果率及结籽率情况,并通过形态学和分子标记的方法研究这些后代群体的遗传变异。结果表明,各种杂交组合的坐果率达到83%～100%,其中以异源四倍体×栽培黄瓜获得含有胚的果实比例较高,为60%～67%,平均每个果实中约有10～20个胚,通过胚胎拯救,成活率接近100%,染色体计数为26条,为异源三倍体。在以栽培黄瓜×异源四倍体的杂交中,获得3个果实,其中1个果实含有大约180个胚,胚胎拯救成活率接近80%,染色体数为26条,为异源三倍体;另外2个果实分别含有60粒和15粒种子,植株染色体数为14条,与栽培黄瓜相同。异源三倍体与栽培黄瓜间杂交产生的含有胚或种子的果实极少。选择其中1个异源四倍体×栽培黄瓜后代含14条染色体的群体(HH1群体)深入研究,有4株表现野生种C.hystrix的多分枝习性,6株的果刺颜色表现野生种C.hystrix的黑色性状,且其果皮成熟颜色均为橘红色,不同于两个原始亲本。通过SSR和RAPD两种标记对HH1群体的遗传研究,19个SSR标记共产生63个等位基因,其中24个(约38.1%)表现出变异,有7个等位基因可能来自于野生种C.hystrix。在400余条随机引物中,有24条引物产生变异位点,在统计的186个位点中,有56个(31.7%)位点出现遗传分离,其中8个位点可能来自于野生种C.hystrix,这表明通过远缘杂交及渐渗杂交过程可将野生种的基因导入栽培黄瓜中。
The percentage of fruit set and seed set in the crosses between amphidiploid （ Cucumis x hyti- vus Chen and Kirkbride, 2n = 38）, and south and north ecotype cucumber cultigens （ C. sativus L. , 2n = 14）, and genetic variation in these progenies were investigated. The percentage of fruit set in all crosses was high （83% - 100% ）. The ratio of fruit with embryo was 60% -67% in the crosses between C. × hytivus and cucumber cultigens. Each fruit had about 10 -20 embryos, which could survive and develop into plantlets through embryo rescue. The chromosome number of these plantlets was 26, as allotriploid. When cucumber cultigens crossed with amphidiploid C. × hytivus, three fruits were obtained. One fruit had about 180 embryos 80% of which could survive through embryo rescue, and the chromosome number was 26. Others oroduced 60 seeds （as HH1 population） and 15 ones with 14 chromosomes similar to that of cucumber cultigens, respectively. Few fruits with embryos or seeds were obtained in the crosses between allotriploid and cucumber cultigens. HH1 population was selected to investigate the genetic variation from morphology and molecular markers. Four plants showed the original parent C. hystrix traits such as black spines on fruit, while six plants had multiple branchng habits and unique morphological characteristics such as orange skin of fruit. Nineteen SSR primer pairs produced 63 alleles in HH1 and 24 alleles （38.1%） were segregated, and seven of them might come from C. hystrix. From 400 arbitrary primers screened, twenty-four produced varied primed sites and a- mong the 186 primed sites 31.7% were segregated. The results suggested that the genes of C. hystrix could be introduced into cucumber through interspecific hybridization and introgression.
出处
《园艺学报》
CAS
CSCD
北大核心
2006年第2期266-271,共6页
Acta Horticulturae Sinica
基金
国家高技术研究发展计划专项资助项目(2002AA241251
2002AA207012
2004AA241120)
国家自然科学基金资助项目(30170644)
教育部跨世纪优秀人才培养计划资助项目
