【作者】 罗向东；

【导师】 陈劲枫；

【作者基本信息】 南京农业大学 ， 蔬菜学， 2006， 博士

【摘要】 酸黄瓜（Cucumis hystrix Chakr．，2n=24，HH）具有栽培黄瓜（C．sativus L．，2n=14，CC）所缺乏的多种优良性状，如耐低温弱光、抗霜霉病和枯萎病等。为了快速有效地利用这些优良性状来改良黄瓜栽培种，本研究在已获得甜瓜属种间双二倍体（C．hytivus Chen & Kirkbride，2n=38）和异源三倍体（2n=26，HCC）的基础上，以酸黄瓜、不同基因型的栽培黄瓜、异源三倍体、双二倍体等为核心材料，创制了4个种间杂交新组合F₁、2个“黄瓜—酸黄瓜”单体异附加系和10个渐渗系新种质；采用细胞遗传学分析技术、同工酶技术以及分子标记技术对这些优良新种质进行了鉴定与评价；另外还初步研究了基因组剂量对三种不同倍性种间杂种表型性状、生理生化指标的影响。具体结果如下： 1．不同基因型栽培黄瓜与酸黄瓜种间杂交及杂种F₁的评价研究 酸黄瓜为短日照植物，因其与栽培黄瓜花期不遇等杂交障碍的存在而使种间杂交难以顺利进行。本研究对酸黄瓜短光照处理40d以上，使得两者花期相遇，成功地进行了酸黄瓜与3种不同基因型栽培黄瓜（“二早子”、“长春密刺”和“4406”）的正反杂交，从中获得了4个杂交新组合的幼胚。采用改良的方法对这4个新组合的杂种胚进行胚胎拯救，再生频率达80％以上，其杂种的真实性通过园艺学性状观察和体细胞染色体鉴定得到了证实。 为了能够快速准确地鉴定酸黄瓜与栽培黄瓜的种间杂种F₁、揭示种间正反交差异，本研究利用新合成的正反交种间杂种F₁[正交：酸黄瓜ד长春密刺”，反交：“长春密刺”×酸黄瓜]及其双亲为试材，比较研究天冬氨酸转氨酶（AAT）、苹果酸脱氢酶（MDH）以及酯酶（EST）3种同工酶在参试材料中的酶谱表达特性。结果发现，正反交种间杂种F₁主要表现为互补双亲的酶带，同时还具有四条杂合带（Aat-1-97，Aat-2-104，Mdh-3-102和Est-5-102）。另外还发现正反交杂种F₁的AAT和MDH同工酶谱分别在酶带数目和强弱上呈现明显差异。表明这三种酶均能准确地鉴定甜瓜属种间杂种F₁的真实性，同时进一步证实了酸黄瓜与栽培黄瓜杂交存在正反交差异。 进一步研究发现，新合成的4个新组合杂种F₁的育性水平差异显著，其中以酸更多还原

【Abstract】 Cucumis hystrix Chakr. （HH, 2n = 24）, a wild relative of the cultivated cucumber, possesses several potentially valuable disease resistance and abiotic stress tolerance traits for cucumber （C. sativus L., CC, 2n = 14） improvement, including tolerance to low irradiance and temperature, resistance to downy mildew, and resistance to fusarim wilt et al. During past years, progress has been made towards achieving gene introgression from C. hystrix following synthesis of a new fully fertile amphidiploid species C. hytivus （HHCC, 2n = 38） and the production of partially-fertile allotriploids hybrids from a mating between C. hytivus and C. sativus （HCC, 2n = 26）. Nevertheless, clear evidence of the introgression of C. hystrix chromosomes or chromosome fragments into a C. sativus background is still lacking. This would be a continuation of numerous efforts to accelerate transferring the desirable traits of C. hystrix into C. sativus.In the present study, C. hystrix, several genotypic cultivated cucumbers, allotriploid and amphdiploid et al were used as core material for further investigation based on our research background. Four novel genotype interspecific hybrids F₁, two monosomic alien addition lines and ten introgression lines have been successfully developed via embryo rescue. Further cytogentic, isozyme and molecular analyses have investigated and confirmed precisely these unique germplasms from interspecific hybridization. The detailed results as following.1. Production and characterization on novel genotypic interspecific hybrids F₁ from Cucumis hystrix Chakr. mating with C. sativus L."Wild cucumber" （Cucumis hystrix, 2n = 24） is a short-day plant. Its hybridization with cultivated cucumber （C. sativus, 2n=14） is hard to be made because of their differential flowering time. In the present study, the flowering time was synchronized by更多还原