Genetic Analysis And Mapping Of IRL1 And BH1 Gene In Rice

Rice is not only the main food crop in China,but also the model plant of monocotyledonous investigation.Coming into 21 century,a newly technology has been built for a new "green revolution" by researching of rice genomes and fountional genomes.Up to now," high yield and high resistance " is the main purposes in rice breeding.One thing,Leaves is a major organ of photosynthesis,meantimes which is the. ultimate form of "source" of yeild.Leaves morphogenesis play an import role of photosynthesis,transpiration and resistance to stress and ultimately affecting rice yield. Another thing,anthocyanin is one of major class of flavonoids,which plays an important role in plant development,in the protection aginst UV radiation,attraction of insects for pollination and plant defense responses.So,we has found two mutants from Nippobare(O. sativa ssp.japonica).In this study,the genetics analysis and mapping were done.The main results are as follows:1.the genetics analysis and fine mapping of irl1 mutant in ricea.Identification of mutant:mutant's leaf angle is larger than wild type and reach a maximum level or droop down at the mature period.leaves curl middlely backward,the height is normalb.The genetic analysis of irl1:During the heading stage,the individual plants in the F₁ and F₂ progenies from the crosses between irl1 and each of ZF802 and TN1 were investigated.in the F₁ plant between the wild type and irl1,all leaf exhibited wild-type phenotype,suggesting the the mutant trait is recessive.on the other hand,in the F₂ populations,both the segregation rates of wild-type and extra glume plant are in accordance with a 3:1 ratio.So,it indicated the invers-rolling leaf trait is controlled by one recessive gene.c.Fine mapping of IRL1 gene:the mutant trait was mapped by mapping-base clone and delimited in the 81.76kb region on the chromosome 2.there are 15 open reading frame(ORF) was predicted within this region.2.Genetic analysis and mapping of brown hull(bh1)mutanta.the mutant's morphological idengtified:brown pigment start to accumulate as a point under the hull and with seed maturing,it diffuses slowly and reach a maximum level in dry seed.b.genetic analysis of mutant's phenotype:For genetic analysis of the bh1 mutant.two F₂ populatin were generated from the crosses between the bh1 mutant and two wild type varieties:TN1(indica),93-11(indica),ZF802(indica) and ChunjiangO6(japonica).All F₁ individuals exhibited wide-type phenotype,while 183 of 748 F₂ individuals derived from bh1 and TN1 were displayed the bh1 phenotype and 565 plants were similar to the wide type.The ratio of mutant phenotype to wild type was 1:3(x²=0.016).This result indicated that the bh1 mutant phenotype was controlled by a single recessive gene in this genetic background.c.Mapping of BH1 gene:To identify where the bh1 locus is located,linkage anlysis was carried out using the F₂ population derived from the cross between the bh1(japonica) mutant and TN1(indica).the BH1 gene is located on the 8.6 region on the long arm of chromosome 2.