The Relationship Between the Stay-Green Trait and Grain Yield in Elite Sorghum Hybrids Grown in a Range of Environments
- D. R. Jordan *a,
- C. H. Huntb,
- A. W. Cruickshankc,
- A. K. Borrella and
- R.G. Henzellc
- a The University of Queensland, Queensland Alliance for Agriculture & Food Innovation Hermitage Research Facility, Yangan Rd., Warwick, QLD 4370, Australia
b Agri-Science Queensland, Tor St., Toowoomba, QLD 4350, Australia
c Agri-Science Queensland, Hermitage Research Station, Yangan Rd., Warwick, QLD 4370, Australia
The stay-green drought adaptation mechanism has been widely promoted as a way of improving grain yield and lodging resistance in sorghum [Sorghum bicolor (L.) Moench] and as a result has been the subject of many physiological and genetic studies. The relevance of these studies to elite sorghum hybrids is not clear given that they sample a limited number of environments and were conducted using inbred lines or relatively small numbers of experimental F1 hybrids. In this study we investigated the relationship between stay-green and yield using data from breeding trials that sampled 1668 unique hybrid combinations and 23 environments whose mean yields varied from 2.3 to 10.5 t ha−1. The strength and direction of the association between stay-green and grain yield varied with both environment and genetic background (male tester). The majority of associations were positive, particularly in environments with yields below 6 t ha−1. As trial mean yield increased above 6 t ha−1 there was a trend toward an increased number of negative associations; however, the number and magnitude of the positive associations were larger. Given that post-flowering drought is very commonly experienced by sorghum crops world wide and average yields are 1.2 and 2.5 t ha−1 for the world and Australia, respectively, our results indicate that selection for stay-green in elite sorghum hybrids may be broadly beneficial for increasing yield in a wide range of environments.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2012. . Copyright © by the Crop Science Society of America, Inc.