Mapping Of QTLs For Nitrogen Utilizing Efficiency In A Rice RILs Population Derived From A Cross Between A Japonica Variety And An Indica Variety

It was performed that mapping of QTLs to control nitrogen utilization efficiency andseveral other related traits by a recombinant inbred line population, derived from a crossbetween Jiucaiqing (japonica) and IR26 (indica) and a molecular genetic maps constructedby SSR markers, at the seeding stage and the maturing stage. Meanwhile, the relationshipbetween root traits and related traits of nitrogen utilization efficiency at the seeding stage,and the relationship between between yield per-plant and related traits of nitrogenutilization efficiency at the maturing stage were analysised. The main results weredescribed as follows:Through liquid culture methods some quantitative trait locus(QTL) were detected thatwas associated with longest roots(RL), root dry-weight(RDW), nitrogen physiologicalefficiency(NPE), nitrogen accumulation in whole plant(WNA), nitrogen concents in shoot(SNC), nitrogen accumulation in shoot(SNA), nitrogen physiological efficiency inshoot(SNPE), nitrogen concents in root(RNC), nitrogen accumulation in root(RNA), andnitrogen physiological efficiency in root(RNPE) in a RILs population consisting of. 150lines at the seedling stage. The result showed that the longest root and the root dry weightwas co-related with nitrogen accumulate in whole plant. Using interval mapping with aLOD threshold of 2.5, the 11 QTLs were detected to be associated with root longest length,root dry weight, nitrogen physiological efficiency, nitrogen accumulation in whole plant,nitrogen concent in shoot, nitrogen accumulation in shoot, nitrogen physiological efficiencyin shoot, nitrogen concent in root, nitrogen accumulation in root and nitrogen physiologicalefficiency in root, respectively. These QTLs distributing at 6 chromosome, could explain6.36％～21.46％of phenotypic variance respectively.Through field growing method some quantitative trait locus(QTL) were detected thatwas associated with nitrogen-utilizing efficiency(NUE), nitrogen transfer ratio(NTR),nitrogen accumulation(NA), nitrogen physiological efficiency(NPE), nitrogen concent inshoot (SNC), nitrogen accumulation in stalk(SNA), nitrogen concent in panicle(PNC) andnitrogen accumulation in panicle(PNA) in the same population at the maturing stage. Theresults showed that the nitrogen accumulation in panicle, the nitrogen accumulation ofwhole plant, nitrogen transfer ratio and nitrogen use efficiency were co-related with yieldper-plant. There were eleven QTLs were detected to be associated with nitrogen-utilizingefficiency, nitrogen transfer ratio, nitrogen physiological efficiency, nitrogen accumulation,nitrogen accumulation in stalk& leaf, and nitrogen accumulation in panicle. These QTLscould explain 7.18％～34.94％of phenotypic variance respectively.