Location: Crop Germplasm Research
Project Number: 6202-21000-034-00
Start Date: Feb 20, 2013
End Date: Feb 19, 2018
The long-term goal of this project is to utilize recent advances in high-throughput genotyping, bioinformatics, and molecular biology to acquire knowledge of sorghum genes and germplasm, and utilize this information to enhance the rate of genetic gain for complex traits such as grain yield through the development of new adapted breeding material. The challenge facing scientists is how to exploit the vast amount of knowledge and tools in molecular biology, genomics, and bioinformatics to accelerate the rate of genetic gain in applied breeding programs. We have targeted several agronomically critical objectives that include introgressing day-neutral flowering response into elite tropical sorghums to create new sources of temperate-zone adapted sorghum germplasm, and identifying genes and alleles in sorghum breeding stocks for pollen fertility restoration, and exploit this information to accelerate development of new parental lines. In ongoing collaboration with scientists at Texas A&M University and private sector plant breeders at MMR Genetic LLC, a classical breeding approach augmented with robust genomic and bioinformatics tools will be used to identify elite tropical sorghums and convert these lines to temperate adaptation. The approach developed under Objective 1 will introduce new germplasm and favorable genes for complex traits, including grain yield, into sorghum breeding programs in the USA and worldwide. In ongoing collaborations with our collaborators in Queensland and Perth, we will use genetic linkage analysis, association mapping methodology, and bioinformatics under Objective 2.A to identify an exhaustive set of fertility restoration (Rf) and partial fertility (Pf) genes. Under Objective 2.B, we will sequence mitochondrial genes and transcripts in CMS- and normal cytoplasms, and examine the effect of Rf genes and unfavorable temperatures on the expression of CMS-associated genes. Through the combined approaches outlined under Objectives 2A. and 2B. we will elucidate the genetic and molecular basis of cytoplasmic male-sterility (CMS) in sorghum A1 cytoplasm. The overall approach of objective 2 will permit breeders to exploit this information to accelerate development of new parental lines for hybrid production fields. Objectives 1 and 2 are complementary, and the knowledge gained under one objective will facilitate the success in all.