Submitted to: Journal of Plant Registrations
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/1/2018
Publication Date: 8/16/2018
Citation: Burke, J.J., Emendack, Y., Hayes, C.M., Xin, Z., Burow, G.B. 2018. Registration of four post-flowering drought tolerant grain sorghum lines with early season cold tolerance. Journal of Plant Registrations. doi:10.3198/jpr2017.12.0086crg.
Interpretive Summary: Four sorghums germplasm lines are being released to the public. These lines contain both early season cold tolerance and post-flowering drought tolerance. Cool temperatures during the early growing season are a major limitation to growing sorghum in temperate areas. These lines germinate rapidly at low temperatures and exhibit excellent seedling vigor. Additionally, these lines maintain green leaves under post-flowering drought and exhibit enhanced seed development under drought. Genetic material of this release is being deposited in the National Plant Germplasm System, where it will be available for research purposes, including development and commercialization of new cultivars.
Technical Abstract: Four sorghum (Sorghum bicolor L.) germplasm lines— PSLS-SGCTB01 (Reg. No.), PSLS-SGCTR02 (Reg. No.), PSLS-SGCTB03 (Reg. No.) and PSLS-SGCTB04 (Reg. No.) — were developed by the USDA-ARS in Lubbock TX, in 2017. The primary purpose for the release of these lines is to provide an alternative germplasm choice with superior early season cold tolerance exemplified by high germination rates and excellent seedling vigor stacked with post-flowering drought tolerance based upon the stay-green trait. The PSLS-SGCTB01 and PSLS-SGCTR02 germplasm lines originated from the plant introduction PI 452605, PSLS-SGCTB03 arose from the plant introduction PI 452808, and PSLS-SGCTB04 arose from the plant introduction PI 452707. The selection of PI germplasm lines for introgression breeding originated from a screening of photoperiod sensitive lines from the Ethiopian sorghum collection in Lubbock, Texas in 2010 for plants that maintained greenness of their leaves at the bottom of the canopy under low light conditions, thereby mimicking the maintenance of green leaves under post-flowering drought stress. Lines derived from selected PI germplasm were evaluated in 2015 and 2016. Comparison of leaf and plant death ratings (LPD) between BTx642 (stay-green check), SC-1506 (non-stay-green check) and the four developed lines with Ethiopian germplasm were determined for plants under irrigated, pre-flowering (PRF), and post-flowering (PSF) drought treatments. These lines were also evaluated for final germination percentages (FPG) and vigor ratings for field cold tests performed in 2015 and 2016. For public and private breeders, these new germplasm lines are an additional source for improving abiotic stress tolerance in diverse sorghum production environments.