Registration of Tx3301 through Tx3360 Sorghum Germplasms with Resistance to Downy Mildew

The sorghum [Sorghum bicolor (L.) Moench] germplasm lines Tx3301 through Tx3360 (Reg. No. GP-733 to GP-792, PI 668030 to PI 668089) were developed and released by Texas A&M AgriLife Research (formerly the Texas Agricultural Experiment Station), College Station, TX, in 2005. All lines were developed from intentional crosses using the pedigree method of plant breeding. Most breeding crosses for these lines were made in Lubbock, TX; a few were made in an Isabela, PR, winter nursery. Selections in subsequent generations that led to the development of these lines were completed in nurseries throughout Texas and Puerto Rico over many years. Screening for downy mildew resistance was completed primarily under field conditions in nurseries where pathotypes 1, 3 and more recently 6 were present. All of these germplasm lines are resistant to pathotypes 3 and 6 of Peronosclerospora sorghi, which cause sorghum downy mildew. They provide the sorghum industry with sources of resistance to the most prevalent pathotypes of P. sorghi in an elite and diverse genetic background. Among the 60 germplasm lines are both seed and pollinator lines, representing an array of combinations for grain color, plant color, and other agronomic traits.