Tx741, Tx777, Tx779, Tx780, and Tx782 inbred maize lines for yield and southern united states stress adaptation

Texas needs maize (Zea mays L.) hybrids with higher yield and better adaptation to the long season and multiple stresses of the state’s environment. Modern commercial inbreds and hybrids have been selected from temperate germplasm that are insufficiently adapted to Texas and other southern US environments. To address this issue, maize inbred lines Tx741 (Reg. No. PL-365, PI 689048), Tx777 (Reg. No. PL-366, PI 689049), Tx779 (Reg. No. PL-367, PI 689050), Tx780 (Reg. No. PL-368, PI 689051), and Tx782 (Reg. No. PL-369, PI 689052) were approved for release by the Texas A&M AgriLife Research breeding program in College Station, TX. These lines were crossed with a variety of commercial testers, and resulting hybrids were grown at multiple locations over several years. Several hybrids from each line produced yields that met or exceeded those of current commercial hybrids. Furthermore, these lines and their hybrids had additional beneficial traits, including high test weight and reduced susceptibility to diseases (including southern rust) and aflatoxin. Derived from unique tropical germplasm or tropical by temperate crosses, these inbred lines were selected under the high day and night temperatures that often cause heat and water stress. Compared with temperate genetics, some of these lines and their hybrids had reduced incidence of southern corn leaf blight and lower susceptibility to Lepidopteran insects. Both lines per se and their hybrids flowered a few days later than commercially available material and had some indications of photoperiod sensitivity. These lines broaden the genetic diversity of US maize, can immediately be used in commercial hybrids, and are useful in breeding new maize lines and hybrids adapted to southern US environments.