中文摘要：

【目的】利用野生草莓资源获得高倍体种间杂种，并与栽培品种进一步回交，以拓宽现代草莓栽培品种遗传背景、培育新品种。【方法】用草莓栽培品种‘汤姬’（2n=8x=56）与中国原产的五倍体野生草莓‘黑龙江7号’（2n=5x=35）杂交，得到1株十二倍体种间杂种YH15-10（2n=12x=84），用之与栽培草莓品种‘宝交早生’和‘哈尼’进行回交，调查亲本及回交后代的倍性、植物学性状、花粉性状、果实性状等。【结果】十二倍体种间杂种YH15-10（2n=12x=84）植株健壮，叶片数少，单株花序数4．4个，每花序花数8—25朵，花量大，果实红色，畸形，最大单果重10．5g，果肉黄白色，有香味。以YH15-10作母本时，均未得到杂种实生苗；以YH15-10作父本时，共得到83株杂种实生苗。十二倍体种间杂种YH15-10的花粉有大、中、小3类，其花粉生活力接近于栽培品种。对宝交早生×YH15-10部分回交后代进行倍性调查，观察到有8x、10x、11x、12x4种倍性的单株，发现了2个高Vc单株IH1—5（10x）和IH1—7（8x），含量分别达0．95mg·g-1和1．07mg·g-1，果实香甜，品质优，但果较小，最大果重分别为10．4g和9．6g。【结论】草莓十二倍体种间杂种YH15-10整合了野生草莓的基因，并开辟了草莓高倍体育种的新途径。用之与八倍体栽培品种进行回交，得到一些果实品质优良、Vc含量高、芳香浓郁的不同倍性高倍体优系，可作为中间育种材料培育新品种。

英文摘要：

[Objective] The backcross between higher ploid interspecific hybrids and strawberry cultivars was beneficial to broadening genetic background of modem cultivated strawberry and breeding of new cultivars. [Method] The dodecploid interspecific hybrid YH15-10 （2n=12x=84） was obtained from the cross between Fragaria x ananassa cv. Yuhime （2n=8x=56） and the wild pentaploid strawberry accession Heilongjiang 7 （2n=5x=35） native to China. The backcross between the dodecaploid interspecific hybrid YH15-10 and strawberry cultivars ＇Hokowase＇ and ＇Honeoye＇ were carried out. The ploidy, botanical characteristics, pollen size and viability, and fruit traits of the offspring were investigated. [Result] The YH15-10 had relatively few leaves, 4.4 inflorescences per plant and 8 to 25 flowers per inflorescence in the open field. The fruits were red, mostly abnormal, in which the maximum fruit weight was 10.5 g. The flesh was yellowish white with obvious aroma. When YH15-10 was used as female parent, no seedlings were obtained. When YH15-10 was used as male parent, 83 offspring was obtained. The dodecploid YH15-10 had large, middle and small pollens, and the pollen viability was similar to that of strawberry cultivars. The octoploid, decaploid, hendecaploid and dodecploid seedlings were obtained from Hokowase x YH15-10. Two seedlings IH 1-5 （10x） and IH 1-7 （8x） with high vitamin C of 0.95 mg·g-1 and 1.07 mg·g-1, respectively, were selected. Their fruits were sweet, aromatic, but small, with the maximum fruit weight of 10.4 g and 9.6 g, respectively. [ Conclusion ] This paper gave a good example for obtaining higher ploid strawberry. The dodecploid interspecific hybrid YH15-10 was helpful to develop new strawberry cultivars. Some seedlings with excellent quality, high vitamin C and high aromatic compound content were obtained from the backcross between the dodecaploid interspecific hybrid YH15-10 and strawberry cultivars. These high ploidy offspring could be further used as the parents to breed new str