Wheat floret survival as related to pre-anthesis spike growth
Wheat floret survival as related to pre-anthesis spike growth
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DOI：
10.1093/jxb/err182
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发表时间：
2011-10-01
影响因子：
6.9
通讯作者：
Slafer, Gustavo A.
中科院分区：
文献类型：
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作者：
Gonzalez, Fernanda G.;Miralles, Daniel J.;Slafer, Gustavo A.
进一步提高小麦产量潜力对于满足未来的粮食需求至关重要。由于产量与可育小花和籽粒的数量有关，因此了解它们的世代基础有助于提高产量。基于(i)开花时可育小花或籽粒数量与穗干重之间的强正相关关系；（ii）当穗以最大速度生长时，小花就会死亡，因此人们总是认为小花的存活取决于穗的生长。然而，这一假设最近受到质疑，认为转移到穗上的同化物并不能决定小花和籽粒的数量，而小花死亡的开始可能是一个与穗生长无关的发育过程。本研究对不同生长条件（温室/田间试验、生长季节、小花原基期光期/遮荫处理）和不同品种类型（冬/春、半矮/标准高、光期敏感/不敏感）的小花原基命运与穗长之间的关系进行了重新分析。在80%的分析案例中，小花死亡的发生与穗生长的开始有最大的相关性；小花死亡率（小花存活的主要决定因素）与花穗重呈负数量关系。由于小花的死亡和存活与花前穗生长有关，因此在育种时关注与花前穗生长有关的性状以进一步提高小麦产量潜力的策略是有价值的。
Further improvements to wheat yield potential will be essential to meet future food demand. As yield is related to the number of fertile florets and grains, an understanding of the basis of their generation is instrumental to raising yield. Based on (i) a strong positive association between the number of fertile florets or grains and spike dry weight at anthesis; and (ii) the finding that floret death occurs when spikes grow at maximum rate, it was always assumed that floret survival depends on the growth of the spike. However, this assumption was recently questioned, suggesting that assimilates diverted to the spike do not determine the number of florets and grains and that the onset of floret death may instead be a developmental process that is not associated with spike growth. In this study, the relationships between the fate of floret primordia and spike growth from six independent experiments that included different growing conditions (greenhouse/field experiments, growing seasons, photoperiod/shading treatments during the floret primordia phase) and diverse cultivar types (winter/spring, semi-dwarf/standard-height, photoperiod sensitive/insensitive) were re-analysed together. Onset of floret death was associated with the beginning of spike growth at the maximum rate in c. 80% of the cases analysed; and the rate of floret death (the main determinant of floret survival) showed a negative quantitative relationship with spike weight at anthesis. As floret death and survival were shown to be linked to pre-anthesis spike growth, the strategy of focusing on traits associated with pre-anthesis spike growth when breeding to increase wheat yield potential further is valuable.