QTL for nodal root angle in sorghum (Sorghum bicolor L. Moench) co-locate with QTL for traits associated with drought adaptation

Mace, E. S. and Singh, V. and Van Oosterom, E. J. and et al, . (2012) QTL for nodal root angle in sorghum (Sorghum bicolor L. Moench) co-locate with QTL for traits associated with drought adaptation. TAG Theoretical and Applied Genetics, 124 (1). pp. 97-109.

[img] PDF - Published Version
Restricted to ICRISAT researchers only

Abstract

Nodal root angle in sorghum influences vertical and horizontal root distribution in the soil profile and is thus relevant to drought adaptation. In this study, we report for the first time on the mapping of four QTL for nodal root angle (qRA) in sorghum, in addition to three QTL for root dry weight, two for shoot dry weight, and three for plant leaf area. Phenotyping was done at the six leaf stage for a mapping population (n = 141) developed by crossing two inbred sorghum lines with contrasting root angle. Nodal root angle QTL explained 58.2% of the phenotypic variance and were validated across a range of diverse inbred lines. Three of the four nodal root angle QTL showed homology to previously identified root angle QTL in rice and maize, whereas all four QTL co-located with previously identified QTL for stay-green in sorghum. A putative association between nodal root angle QTL and grain yield was identified through single marker analysis on field testing data from a subset of the mapping population grown in hybrid combination with three different tester lines. Furthermore, a putative association between nodal root angle QTL and stay-green was identified using data sets from selected sorghum nested association mapping populations segregating for root angle. The identification of nodal root angle QTL presents new opportunities for improving drought adaptation mechanisms via molecular breeding to manipulate a trait for which selection has previously been very difficult.

Item Type: Article
Additional Information: We thank the Australian Grains Research and Development Corporation (GRDC; http://www.grdc. com.au) and the Australian Research Council (ARC) through ARClinkage project LP0560484 for part of the financial support for this research.
Uncontrolled Keywords: QTL Mapping
Author Affiliation: Agri-Science Queensland, Department of Employment, Economic Development and Innovation, Hermitage Research Facility, 604 Yangan Road, Warwick, QLD 4370, Australia
Subjects: Crop Improvement > Genetics/Genomics
Divisions: Sorghum
Depositing User: Mr Siva Shankar
Date Deposited: 04 Sep 2012 06:25
Last Modified: 04 Sep 2012 06:26
Official URL: http://dx.doi.org/10.1007/s00122-011-1690-9
URI: http://eprints.icrisat.ac.in/id/eprint/7692

Actions (login required)

View Item View Item