CIMMYT, Int, Km. 45 Carretera Mexico-Veracruz, CP 56130, El Batan, Texcoco, Mexico.
Theor Appl Genet. 2010 Apr;120(6):1107-17. doi: 10.1007/s00122-009-1238-4. Epub 2010 Jan 1.
While canopy temperature (CT) shows a strong and reliable association with yield under drought and heat stress and is used in wheat breeding to select for yield, little is known of its genetic control. The objective of this study was to determine the gene action controlling CT in five wheat populations grown in diverse environments (heat, drought, and well-irrigated conditions). CT showed negative phenotypic correlations with grain yield under drought and well-irrigated environments. Additive x additive effects were most prevalent and significant for all crosses and environments. Dominance and dominance x dominance gene actions were also found, though the significance and direction was specific for each environment and genotypic cross. The use of CT as a selection criterion to improve tolerance to drought was supported by its significant association with grain yield and the genotype differences observed between cultivars. Our results indicated that genetic gains for CT in wheat could be achieved through conventional breeding. However, given some dominance and epistatic effects, it would be necessary to delay the selection process until the frequency of heterozygous loci within families is reduced.
冠层温度（CT）在干旱和热胁迫下与产量表现出强烈且可靠的关联，并且在小麦育种中用于选择产量，但其遗传控制知之甚少。本研究的目的是确定在不同环境（热、干旱和充分灌溉条件）下生长的五个小麦群体中控制 CT 的基因作用。CT 在干旱和充分灌溉环境下与籽粒产量呈负表型相关。所有杂交种和环境中均以加性 x 加性效应为主导且最为显著。也发现了显性和显性 x 显性基因作用，但每个环境和基因型杂交种的效应均具有特异性。CT 作为一种提高耐旱性的选择标准得到了支持，因为它与籽粒产量显著相关，并且在品种之间观察到了基因型差异。我们的结果表明，通过传统育种可以实现小麦 CT 的遗传增益。然而，鉴于存在一些显性和上位性效应，有必要延迟选择过程，直到家族内杂合位点的频率降低。
