Yuan Y L, Zhang T Z, Guo W Z, Shen X L, Yu J, Kohel R J
Key Laboratory of Crop Genetics & Germplasm Enhancement, Ministry of Education, Nanjing Agricultural University, Nanjing 210095, China.
Yi Chuan Xue Bao. 2001;28(12):1151-61.
A G. anomalum introgression line, 7235, characterized as super quality fiber properties, was used to identify molecular markers linked to fiber property QTLs. By use of (7235 x TM-1)F2 in Nanjing and College Station, USA, and (7235 x TM-1)F3 in Nanjing and Hainan. Bulked segregation analysis was employed to produce 3 pairs of mixed DNA pools for fiber strength, micronaire and fiber length according to individual value of (7235 x TM-1)F2 and F2:3. A total of 221 pairs of SSR primers, 1,840 arbitrary 10-mer oligonucleotide primers and 77 ISSR primers were used to screen polymorphism between two parents, and 3 pairs of bulked DNA pools. Fifteen markers amplified by thirteen primers were identified to be linked with fiber quality QTLs through DNA polymorphism surveying between the parents, and then paired bulked DNAs, and screening the individual plant of (7235 x TM1)F2. Linkage test indicated 15 markers could be mapped to three linkage groups. In the first linkage group, eight markers (two SSR and six RAPD markers) associated with fiber strength were tightly linked with 2.2 cM interval genetic distance on average, and located on chromosome 10 in cotton. Two major QTLs for fiber quality characters were identified. One for fiber strength could explain 35% of the phenotypic variation in F2, and 53.8% in F2:3 at Hainan, which has the greatest single QTL effect of fiber strength and could be identified in all four environments, and tightly linked to 6 RAPD markers and 2 SSR markers with genetic distance no more than 16 cM in chromosome 10, in which FSRl933 is the nearest with the distance no more than 0.6 cM. One QTL linked to FMR1(603) for Micronaire could explain 7.8% of the phenotypic variation in F2, and 25.4% in F2:3 at Hainan, and expressed in all four environments. One QTL linked to FLR1(1550) for fiber length could explain 9.5% of the phenotypic variation in F2:3 at Hainan, very little in other environments. So they can be used in marker-assisted selection in increasing fiber quality of commercial cultivars.
以具有优质纤维特性的异常棉渐渗系7235为材料，鉴定与纤维品质QTL连锁的分子标记。利用南京和美国大学城的(7235×TM-1)F2群体，以及南京和海南的(7235×TM-1)F3群体。根据(7235×TM-1)F2和F2:3单株纤维强度、马克隆值和纤维长度的表型值，采用混合群体分离分析法构建了3对混合DNA池。用221对SSR引物、1840条10碱基随机寡核苷酸引物和77条ISSR引物，对两个亲本及3对混合DNA池进行多态性筛选。通过亲本间、混合DNA池间的DNA多态性分析，以及对(7235×TM1)F2单株的筛选，鉴定出13条引物扩增出的15个标记与纤维品质QTL连锁。连锁分析表明，15个标记可定位到3个连锁群。在第一个连锁群中，8个与纤维强度相关的标记（2个SSR标记和6个RAPD标记）平均以2.2 cM的遗传距离紧密连锁，位于棉花第10号染色体上。鉴定出2个纤维品质性状的主效QTL。一个控制纤维强度的QTL在海南的F2中可解释35%的表型变异，在F2:3中可解释53.8%的表型变异，是纤维强度单QTL效应最大的，在4个环境中均可检测到，与第10号染色体上6个RAPD标记和2个SSR标记紧密连锁，遗传距离不超过16 cM，其中FSRl933最近，距离不超过0.6 cM。一个与马克隆值相关的QTL FMR1(603)在海南的F2中可解释7.8%的表型变异，在F2:3中可解释25.4%的表型变异，在4个环境中均有表达。一个与纤维长度相关的QTL FLR1(1550)在海南的F2:3中可解释9.5%的表型变异，在其他环境中解释率很低。因此，它们可用于辅助选择提高商业品种的纤维品质。
