Genetics and Breeding Improvement for Panicle Type in Rice

Panicle type is one of the key agronomic traits closely related to plant types and yield,and the innovation of ideal plant architecture with large-panicle has been an important part of rice high yield breeding in the future.Six types and 19 sub-types of classification for panicle were reviewed,such as the degree of erect panicle type,grain number per panicle,weight per panicle,seed density and so on.So far,at least 200 kinds of panicle type mutants were obtained,1386 QTLs for rice panicle types(involving panicle length,panicle number,grain width,grain number per panicle,and seed setting rate) were identified.More than 16 panicle type-related QTLs including Dep1,Ghd7,Gn1a,Ipa1 and GW2 were cloned.Four kinds of breeding improvement ways for erect panicle type,large-panicle-type,heavy panicle type and late-stage vigor type rice were emphatically reviewed,and molecular breeding strategies of double-gene polymerization were summarized such as Gn1/sd1 or Gn1/DEP1 using new cloned panicle-type genes.The development of panicle-type research in rice will provide more methods and thoughts for ideal plant architecture with large-panicle and super rice with erect-largepanicle-type.