The Identification And Gene Preliminary Mapping Of A New Maize Inflorescence Meristem Development Mutant

Maize is an important food, feed, and economic crops. It has been the country’s largest acreage crop and is also an important model plant for genetic research. The inflorescence of maize is important reproductive organs. Throughout the life cycle of the Maize, inflorescence development is extremely important and a critical developmental period, and is also the most complex developmental processes. The substance of the maize inflorescence is the process of differentiation and development of the inflorescence meristem, the mutation of the inflorescence meristem at any stage and type will have a direct impact on the establishment of the ultimate female, tassel morphology and function. Through the study of developmental mutants of some of the maize inflorescence meristem, predecessors have a more profound understanding from the morphological and molecular level in development of maize inflorescence. In our earlier research, We isolated natural, stable homozygous inflorescence meristem development mutant fea*-9LB030from the self-sterile normal maize inbred lines9LB030,whose traits different from those most of the inflorescence meristem development mutants reported, so it is necessary to carry out in-depth study.In this study, we do some research, the morphological identification, genetic analysis and gene preliminary mapping, on maize inflorescence meristem development mutants fea*-9LB030.The main results are as follows:1. The morphological identification of the mutant fea*-9LB030, we found that this mutant different from the currently reported in the maize inflorescence meristem development mutant. The main traits are:the upper part of the normal development of the female inflorescence often spread additional incomplete rows, more than the wide-type and irregular, leading to the top of the female inflorescence flat and wide. The male inflorescence is smaller. The main rachis and branches are shorter and thicker, whose spikelets are in pairs, irregular arrangement and high density. Occasionally multiple spikelets pairs (MSP) and multiple florets (MF)are found in the tassels.2. The genetic analysis showed that the mutant fea*-9LB030was controlled by a recessive gene. The inflorescences of F1were wild-type. In F2generation the proportion of mutants and wide-type was accord with1:3, and also the proportion of mutants and wide-type was accord with1:1in back crossing group.3. Gene preliminary mapping shows that:mutant gene fea4was located in the chromosome1,and at the same side of the umc2244and umc1685,and the distance between inflorescence mutations gene fea.4and the two SSR molecular markers were44.4cM and36.6cM respectively.4. The mutant fea*-9LB030traits are different from the maize inflorescence meristem mutant which has been reported, and the gene has been preliminary positioned in the maize chromosome1,1.01bin. There is no other similar gene reported in this area. Combined with its phenotypic characteristics, the gene was named fasciated ear4(fea4) temporary.In summary, this experiment show that the mutant fea*-9LB030is a new maize inflorescence meristem development mutants. This results laid a foundation for the future efforts to achieve fine mapping and cloning of the gene.