Evaluation of Interallelic waxy, Heterowaxy, and Wild-Type Grain Sorghum Hybrids

Authors

M. K. Yerka, USDA–ARSFollow
J. J. Toy, University of Nebraska-LincolnFollow
Deanna L. Funnell-Harris, USDA-ARSFollow
Scott E. Sattler, USDA-ARSFollow
J. F. Pedersen, USDA–ARSFollow

Date of this Version

12-20-2015

Citation

Published in Crop Sci. 56:113–121 (2016). doi: 10.2135/cropsci2015.03.0151.

Comments

U.S. government work.

Abstract

Four near-isogenic Wheatland x 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 wx^b and wild-type (WT) Wheatland as female parents with wx^a 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 (wx^b x wx^a) hybrid was 330 kg ha⁻¹ greater than the WT x WT hybrid (P = 0.0482). The wx^b x Wx hybrid had the highest grain yield, 633 kg ha⁻¹ greater than the WT (P = 0.0003). Amylose starch content was lowest for wx^b x wx^a (7.66 g kg⁻¹), intermediate for wx^b x Wx and Wx x wx^a (25.06 and 27.20 g kg⁻¹, respectively); and highest for WT x 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.