Developmental traits affecting low-temperature tolerance response in near-isogenic lines for the vernalization locus Vrn-A1 in wheat (Triticum aestivum L. em Thell)
Developmental traits affecting low-temperature tolerance response in near-isogenic lines for the vernalization locus Vrn-A1 in wheat (Triticum aestivum L. em Thell)
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DOI：
10.1093/aob/mcf102
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发表时间：
2002-05-01
期刊：
影响因子：
4.2
通讯作者：
Fowler, DB
中科院分区：
文献类型：
--
作者：
Limin, AE;Fowler, DB
对禾谷类作物耐低温性的研究通常会发现vrn-Al春化基因或其同源基因在相关基因组中的区域。本研究选择了两个生长习性由Vrn-Al（春性）和vrn-Al（冬性）等位基因决定的品种（一个非耐寒春小麦品种和一个极耐寒冬小麦品种），构建了相互近等基因系（NIL）。然后用这些品系来确定物候发育速率与LT耐受基因表达的程度和持续时间之间的关系。每个等位基因在不耐寒春小麦"马尼图"和极耐寒冬小麦"北星"的遗传背景中分离。在0-98 d的4 ℃驯化期内，定期测定各等位基因对物候发育和低温耐受性（LT_（50））的影响。营养/生殖的过渡，确定最终叶数（FLN），被认为是一个主要的发展因素影响LT的耐受性。拥有一个春化的要求增加了营养生长期的长度和LT的耐受性。同样，增加FLN在春季Norstar和冬季马尼图近等基因系推迟了他们的营养/生殖过渡，并增加了他们的LT耐受性相对于马尼图。虽然冬季马尼图近等基因系的FLN低于春季Norstar近等基因系，但它们能够通过增加叶时（连续叶片出现之间的间隔）将其营养阶段延长至相似的长度。谷类植物有四种延长营养生长期的方式，所有这些方式都延长了耐低温基因更高表达的时间：（1）春化;（2）光周期反应;（3）增加叶片数量;（4）增加叶时长度。(C)2002年《植物学年鉴》（Annals of Botany Company）
Investigation of low-temperature (LT) tolerance in cereals has commonly led to the region of the vrn-Al vernalization gene or its homologue in related genomes. Two cultivars, one a non-hardy spring wheat and one a very cold-hardy winter wheat, whose growth habits are determined by the Vrn-Al (spring habit) and vrn-Al (winter habit) alleles, were chosen to produce reciprocal near-isogenic lines (NILs). These lines were then used to determine the relationship between rate of phenological development and the degree and duration of LT tolerance gene expression. Each allele was isolated in the genetic backgrounds of the non-hardy spring wheat 'Manitou' and the very cold-hardy winter wheat 'Norstar'. The effects of each allele on phenological development and low-temperature tolerance (LT50) were determined at regular intervals over a 4 degreesC acclimation period of 0-98 d. The vegetative/reproductive transition, as determined by final leaf number (FLN), was found to be a major developmental factor influencing LT tolerance. Possession of a vernalization requirement increased both the length of the vegetative growth phase and LT tolerance. Similarly, increased FLN in spring Norstar and winter Manitou NILs delayed their vegetative/reproductive transition and increased their LT tolerance relative to Manitou. Although the winter Manitou NILs had a lower FLN than the spring Norstar NILs, they were able to extend their vegetative stage to a similar length by increasing the phyllochron (interval between the appearance of successive leaves). Cereal plants have four ways of increasing the length of the vegetative phase, all of which extend the time that low-temperature tolerance genes are more highly expressed: (1) vernalization; (2) photoperiod responses; (3) increased leaf number; and (4) increased length of the phyllochron. (C) 2002 Annals of Botany Company.