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采用胚胎拯救方法 ,首次成功实现了栽培黄瓜 (Cucumis sativus L.,2 n=1 4)与同属野生种 C.hystrix Chakr.(2 n=2 4 )间可重复的种间杂交。杂交 F1植株形态一致。其中多分枝、密棕茸毛 (尤其是在花瓣和雌蕊上 )、桔黄色花冠及卵圆形果实这些特征与亲本 C.hystrix相似 ,而第一雌花节位则与亲本黄瓜 (C.sativus)相似。其它性状如株径、节长、叶和花的形状和大小等都介于双亲之间而呈中间型。将杂种 F1植株自交并与两亲本进行回交 ,结果表明 F1杂种的雄蕊和雌蕊都是不育的。这可能是由于杂种染色体数目为奇数 (2 n=1 9,其中 7条来自黄瓜 ,1 2条来自野生黄瓜 ) ,缺乏同源性而导致减数分裂不正常。利用体细胞无性系突变方法 ,对杂种的染色体数进行了加倍。流动细胞计量仪测定表明 ,加倍的 F1植株 (双二倍体 )占再生植株的 7.3 %,形态一致 ,其 DNA含量为 2 .3 5 pg,而 F1(二倍体 )的含量为 1 .1 7pg。新合成的双二倍体植株能释放花粉 ,并且能形成含种子的果实。对生长和发育、营养价值及抗性等方面初步研究表明 ,这一新物种可望成为一新型作物种 ,在未来农业中占有一席之地。通过不同杂交可形成两种类型的果实 :一种为腌渍类型 ,该株系每株可着生 3 0多个大约 1 0 cm长的果实 ,可一次性采收 ;另一种为耐弱光类
The embryo rescue method was used for the first time to achieve repeatable interspecific hybridization between cucumber (Cucumis sativus L., 2 n = 14) and the same wild species C. hystrix Chakr. (2 n = 24). Hybrid F1 plant morphology consistent. Among them, the characteristics of multi-branched, dense brown hair (especially on petals and pistils), orange-colored corolla, and oval fruit are similar to those of C. hystrix, while the first female flower node is similar to C. sativus . Other traits such as diameter, length, leaf and flower shape and size are intermediate between the parents. The hybrid F1 plants were selfed and backcrossed with their parents. The results showed that both the stamens and pistils of F1 hybrids were sterile. This may be due to an odd number of hybrid chromosomes (2 n = 19, of which 7 are from cucumbers and 12 from wild cucumbers), resulting in a lack of homology leading to meiosis abnormalities. Using somaclonal mutation methods, the number of hybrids was doubled. Flow cytometry measurements showed that doubling F1 plants (diploids) accounted for 7.3% of regenerated plants with the same morphology with a DNA content of 2.35 pg and F1 (diploid) content of 1.1 7pg. The newly synthesized diploid plants release pollen and form seed-bearing fruits. Preliminary studies on growth and development, nutritional value and resistance have shown that this new species is expected to become a new crop species with a place in agriculture in the future. Two types of fruit can be formed by different crosses: one is the pickled type, which can produce more than 30 fruits of approximately 10 cm in length per plant and can be harvested once, while the other is resistant to weak light class