Identification Of Cotton Genes In Regulating Plant Architecture

Cotton is one of the important crops in China, and plays a significant role in the national economy as well as in our daily life. Currently, studies on cotton mainly focus on yield, fiber quality and stress tolerance. Less research focuses on plant architecture. Previous results showed that plant architecture is mainly regulated by plant hormones. As we know, brassinosteroids (BRs), a class of plant hormones, mainly regulate plant stem elongation and promote cell division. In cotton, BR can effectively regulate cotton stalk height in addition to promoting fiber elongation. Our purpose is to identify novel cotton genes regulating cotton architecture.In this research, we constructed a cotton cDNA expression library for screening genes regulating plant architecture. Our rational is that we should be able to identify cotton genes regulating brassinosteroid signaling if the genes can suppress bril-5 or bril-9 phenotypes upon overexpression. Or, we can islote genes which can modify the architectures of bril-5 or bril-9 but may have nothing to do with the brassinosteroid signaling. By a large scale genetic screen, we have isolated seven genetic modifiers of bril-5 or bril-9. These plants exhibit significant differences in plant height, leaf type, petiole length and fertility compared with control plants. Several of the genes have been cloned. In the future, we will confirm that these are the genes responsible for the phenotypes. These studies may help us to manipulate cotton architecture in the near future for its optimal yield and agricultural application via genetic engineering.