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研究稻作抗旱的根系特征及其遗传机理,在作物育种程序上改良作物根系性状,提高作物抗旱性,为水旱稻杂交选育抗旱高产品种提供理论依据。本研究利用187个SSR标记和1套具有180个家系的旱稻渗入系群体BC3F7构建遗传连锁图,采用单标记分析法,对拔节期根系的6个性状(最长根长、粗根数、总根数、平均最粗根粗、根干重、总干重)进行QTL定位。拔节期检测到QTL共56个,其中影响上述6个性状的QTL数目分别是9、10、3、12、9和13,其总贡献率分别为43%、44%、19%、70%、39%和68%。另外,在检测到的QTL中除与总根数有关的有2个来自毫格劳的等位基因降低性状值以外,其位点毫格劳的等位基因均增加性状值。92.8%的渗入位点对以沈农265为遗传背景的渗入系的根系6个性状有促进作用;定位到的影响不同根系性状的QTL多数成簇排列;在RM1261附近定位到影响3个性状的QTL,推测是一个与根系抗旱性状密切相关的基因区域。
Studied the root system and its genetic mechanism of drought resistance in rice, improved crop root traits in crop breeding programs, improved crop drought resistance and provided theoretical basis for cross breeding of drought-resistant and high-yielding varieties of paddy rice. In this study, 187 SSR markers were used to construct a genetic linkage map of BC1F7 in a group of upland rice infested with 180 pedigrees. Single marker analysis was used to analyze 6 traits (longest root length, Root number, the average coarsest root, root dry weight, total dry weight) QTL mapping. A total of 56 QTLs were detected at the jointing stage, of which the QTLs affecting the above six traits were 9, 10, 3, 12, 9 and 13, respectively, with the total contribution rates being 43%, 44%, 19%, 70% 39% and 68%. In addition, except for two alleles with milligrams, which are related to the total number of root traits, the alleles at the locus Milligrass all increased trait values. 92.8% of introgression sites promoted the six traits of root traits that infiltrated with Shennong 265 as a genetic background. Most of the QTLs mapped to different root traits clustered in the vicinity of RM1261 and were mapped to three traits affecting three traits QTL, presumed to be closely related to the root drought resistance gene area.