利用高代回交群体定位醋栗番茄发芽期与幼苗期耐冷QTL

以醋栗番茄LA722和普通番茄9706为材料，利用发芽期大规模低温胁迫筛选方法和AB-QTL方法对野生醋栗番茄发芽期和幼苗期的耐冷性QTL进行了定位研究，构建了包括273个BC3S1株系的高代回交作图群体，以种子相对发芽指数和苗期耐冷指数作为耐冷指标，检测到5个与发芽期耐冷性相关的QTLs，分别位于第1、2、5、11染色体上，2个与幼苗期耐冷性相关的QTLs，分别位于第2和第8染色体上。其中，控制发芽期耐冷性的qRGI-2-1和qRGI-5-1贡献率分别为12.8%和32.9%。有12个单株的自交后代（BC3S2）在发芽期和幼苗期的耐冷性都达到或优于LA722的水平，且果实质量等农艺性状均接近或优于普通番茄9706，可作为番茄耐冷育种材料。

QTL Analysis of Cold Tolerance from Solanum pimpinellifolium During Seed Germination and Seedling Stages Using Advanced Backcross Population

An advanced backcross population of 273 BC3S1 individuals was developed derived from the cross Solanum pimpinellifolium LA722 × Solanum lycopersicum 9706 and a map was constructed containing 35 CAPS markers and 62 SSR markers. The QTLs controlling cold tolerance were mapped in the wild tomato Solanum pimpinellifolium LA722 by mass screening test under cold stress. Using MQM mapping method, seven QTLs controlling cold tolerance were mapped in five chromosomes. The five QTLs coffering cold-tolerance during seed germination were mapped to chromosomes 1, 2, 5 and 11, while the two QTLs coffering cold-tolerance during seedling stage were mapped to chromosome 2 and 8. The QTLs on chromosomes 2 and 5 (qRGI-2-1 and qRGI-5-1) could explain 12.8% and 32.9% of the phenotypic variance, respectively. The cold tolerance of 12 tomato self-offspring (BC3S2) during seed germination and seedling stages was at or better than that of LA722 and the agronomic traits, such as fruit weight, were also close to or better than normal tomato variety 9706. So these lines can be used as tomatocold-resistant breeding materials.