Dilooshi Weerasooriya1, Ananda Yapa Bandara2, Scott Bean3, Floyd Dowell3, Kamaranga Peiris3 and Tesfaye Tesso4, (1)Department of Agronomy, Kansas State University, Manhattan, KS (2)Department of Plant Pathology, Kansas State University, Manhattan, KS (3)USDA-ARS, Manhattan, KS (4)Agronomy, Kansas State University, Manhattan, KS
Developments in weed control technology for sorghum (Sorghum bicolor (L.) Moench) have not kept pace with those in other economically important crops. As a result sorghum has lost tremendous acreage to crops that offer better weed control options. The discovery of herbicide resistance mutation in wild/weedy sorghum species generated interest in the development of herbicide resistant sorghum hybrids. Genetic mutation for resistance to Acetolactate synthase (ALS) inhibitor herbicides were incorporated into cultivated sorghum and resistant germplasm was distributed to the industry. Further research over the last several years led to the development of agronomically adapted seed and pollinator parent lines. In this study we report on agronomic potential and nutritional properties of new ALS resistant sorghum inbreds and hybrids. The study also addresses some of the public concerns on the possible undesirable effects of genome dragging from resistance donor parents. Thirty three inbreds and 30 hybrids developed through crosses between ALS resistant and susceptible lines were evaluated in replicated plots along with commercial checks. Data were collected on various agronomic parameters as well as nutritional and grain quality attributes. Resistant hybrids were shown to have similar adaptation and yield potential as susceptible regular hybrids. Few of the resistant hybrids and inbreds have higher protein content while the majority have nutritional attributes (protein, starch, fat and ash) and mineral profiles (P, K, Ca, Mg, Zn, Fe, Cu and Mn) comparable to that of regular lines and hybrids. While, reduced vigor and interveinal chlorosis is observed on young seedlings of some ALS resistant inbreds and hybrids, these phenotypes quickly disappear at advanced seedling stage and seem to have little or no effect on final yield and other crop parameters.