Author
Yerka, Melinda | |
Toy, John | |
Funnell-Harris, Deanna | |
Sattler, Scott | |
Pedersen, Jeffrey |
Submitted to: Crop Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 5/11/2015 Publication Date: 12/30/2015 Publication URL: http://handle.nal.usda.gov/10113/62101 Citation: Yerka, M.K., Toy, J.J., Funnell-Harris, D.L., Sattler, S.E., Pedersen, J.F. 2015. Evaluation of interallelic waxy, heterowaxy, and wild-type grain sorghum hybrids. Crop Science. 56:113-121. DOI: 10.2135/cropsci2015.03.0151. Interpretive Summary: Starch with reduced amylose content from waxy maize and sorghum would have advantages in ethanol production, due to shorter fermentation times and less input energy demand, and in the food industry due to improved pasting properties. Sorghum is more drought-tolerant than maize, so production of low-amylose starch could be accomplished where decreased water use is desired. However, commercial sorghum grain is typically produced with hybrids. To facilitate waxy sorghum utilization, the USDA-ARS evaluated four near-isogenic grain sorghum hybrids: one waxy (low-amylose), one normal, and two heterozygous for the waxy gene (heterowaxy, intermediate amylose). Grain yield of the waxy and heterowaxy hybrids was equal to or greater than that of the normal hybrid. The waxy and heterowaxy hybrids evaluated in this study are promising options for commercial production of reduced-amylose starches in a drought-tolerant crop. Technical Abstract: Four near-isogenic Wheatland × Tx430 grain sorghum [Sorghum bicolor (L.) Moench] hybrids differing in allelic status at the Waxy locus were grown in yield trials to determine their potential to expand existing sources of low-amylose starch. The hypothesis tested was that agronomic performance and grain yield do not differ among hybrid genotypes. Hybrids were generated in a two-by-two factorial design using wxb and wild-type (WT) Wheatland as female parents with wxa and WT Tx430 as male parents. Yield trials were conducted at two Nebraska locations in 2009 and 2010. No differences were observed for field emergence, but grain yield of the interallelic waxy (wxb × wxa) hybrid was 330 kg ha-1 greater than the WT × WT hybrid (P = 0.0482). The wxb × Wx hybrid had the highest grain yield, 633 kg ha-1 greater than the WT (P = 0.0003). Amylose starch content was lowest for wxb × wxa (7.66 g kg-1), intermediate for wxb × Wx and Wx × wxa (25.06 and 27.20 g kg-1, respectively); and highest for WT × WT (34.80 g kg-1) (n = 4, P < 0.0001). The waxy and heterowaxy hybrids evaluated in this study are promising options for commercial production of starches with reduced amylose contents in a drought-tolerant crop. |