水稻耐亚铁毒QTLs的定位

亚铁毒是潜育性水稻土中限制水稻产量的主要因子。利用龙杂8503／IR64的F2和等价的F3群体，在营养液中培养来定位耐亚铁毒的QTLs。通过构建101SSR标记的遗传连锁图谱来确定耐亚铁毒QTLs的位置和特性。借助叶片棕色斑点指数、株高和最大根长3个性状，利用营养液在水稻苗期来评价F2单株、F3群体和亲本龙杂8503、IR64，共检测到叶片棕色斑点指数、株高和最大根长的QTLs20个，分布在水稻的10条染色体上，表明这些性状受多基因控制。控制叶片棕色斑点指数的QTLs分别定位在第1染色体的RM315-RM212、第2染色体的RM6-RM240和第4染色体的RM252-RM451之间。与前人的研究结果比较发现：1）位于第4染色体RM252-RM451之间的控制叶片棕色斑点指数的QTL与水稻功能图谱上控制叶绿素含量减少的QTL的位置一致。另一个位于第1染色体的RM315-RM212之间的控制叶片棕色斑点指数的QTL与水稻功能图谱上位于C178-R2635之间控制叶绿素含量的QTL连锁。2）位于第2染色体RM6-RM240之间的第3个控制叶片棕色斑点指数的QTL与位于RZ58-CD0686的控制钾吸收的QTL连锁。

Mapping of QTLs for Ferrous Iron Toxicity Tolerance in Rice(Oryza sativa L.)

Ferrous iron toxicity is the main factor limiting the productivity of rice in gleyic paddy soils.In this study,an F2 and an equivalent F3 populations derived from a japonica/indica cross of rice,Longza8503/IR64,were raised under iron-enriched solution cultures ,and used to map QTLs controlling ferrous iron toxicity tolerance.A genetic linkage map consisting of 101 SSR markers was constructed to determine the position and nature of quantitative trait loci (QTLs) affecting Fe2+ toxicity tolerance.Three characters,i.e.,leaf bronzing index (LBI),plant height (PH) and maximum root length (MRL) were evaluated for the F2 plants and F3 lines and the parents at the seedling stage in nutrient solution.A total of 20 QTLs for LBI,PH and MRL under the Fe2+ stress were detected over 10 of the 12 rice chromosomes,reflecting multigenic control of these traits.QTLs controlling LBI were located at the region of RM315-RM212 on chromosome 1,RM6-RM240 on chromosome 2 and RM252-RM451 on chromosome 4.Compared with other mapping results:1) the QTL for LBI located at the region of RM252-RM451 on chromosome 4 was identical with the QTL for decreased chlorophyll content on a rice function map.Another QTL for LBI located at the region of RM315-RM212 on chromosome 1 was linked with the QTL for chlorophyll content which located at the region of C178-R2635 on a rice function map.2)The third QTL for LBI located at the region of RM6-RM240 on choromosome 2 was linked with the QTL for potassium uptake located at the region of RZ58-CDO686 under potassium deficiency stress.