Agronomic evaluation of a tiller inhibition gene (tin) in wheat.: II.: Growth and partitioning of assimilate
Agronomic evaluation of a tiller inhibition gene (tin) in wheat.: II.: Growth and partitioning of assimilate
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DOI：
10.1071/ar04153
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发表时间：
2005-01-01
影响因子：
--
通讯作者：
van Herwaarden, AF
中科院分区：
文献类型：
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作者：
Duggan, BL;Richards, RA;van Herwaarden, AF
已建议在经常遭受终端干旱的地区种植分蘖减少的小麦。通过抑制分蘖的基因（tin）的渗入，一种具有产生较少茎的遗传倾向的小麦植物现在是可能的。本研究以几个不同小麦品种为材料，研究了tin基因对小麦分蘖、光截获、干物质生产和分配动态的影响。商业品种和它们的近等基因对不同的锡基因的存在下，生长在良好的浇水管，也在该领域在澳大利亚东南部终端干旱是常见的。分蘖数，光截获，叶面积指数（LAI），生物量，和生物量的分配记录在整个生长季节的不同时间间隔。水溶性碳水化合物（WSC）的水平在田间生长的植物茎也确定在开花和成熟的一些环境中。在试管和田间环境中，具有tin基因的品系与自由分蘖的品系以相同的速率产生分蘖，但更快地停止分蘖。在自由分蘖株系每平方米产生超过1000个芽的条件下，含有tin基因的株系每平方米产生600个芽。然而，成熟时，可育穗数为450和350/m2的线与锡基因，分别。尽管分蘖差异很大，但在LAI、整个季节的光截获和生物量方面只有很小的差异。在生物量的比例分配上存在小的差异，锡线在开花时将更多的生物量分配给穗，并在茎中储存更多的WSC。干重分布因遗传背景不同而异，但总的来说，tin基因增加了叶面积比和根冠比，但降低了比叶面积。因此，锡基因可能是有利的终端干旱。这将来自开花前减少的光截获，从而在灌浆期间可能有更大的蒸腾作用，以及茎碳水化合物储存和再动员的更大能力。这些因素与含有tin基因的品系具有更大的收获指数和籽粒重量是一致的。
Wheats with reduced tillering have been proposed for areas regularly subject to a terminal drought. A wheat plant with a genetic disposition to produce fewer stems is now possible through the introgression of a gene that inhibits tillering ( tin). This study was conducted to determine the effect of the tin gene on the dynamics of tillering, light interception, and dry-matter production and partitioning in several different cultivars of wheat. Commercial cultivars and their near-isogenic pairs differing in the presence of the tin gene were grown in well-watered tubes and also in the field in south-eastern Australia where terminal drought is common. Tiller number, light interception, leaf area index (LAI), biomass, and the partitioning of biomass were recorded at various intervals throughout the growing season. Water-soluble carbohydrate (WSC) levels in the stems of field-grown plants were also determined in some environments at anthesis and maturity. In tubes and in field environments, lines with the tin gene produced tillers at the same rate as their free tillering counterparts but ceased tillering sooner. Under conditions where the free tillering lines produced over 1000 shoots/m(2), lines containing the tin gene produced 600 shoots/m(2). However, by maturity, fertile spike numbers were 450 and 350/m(2) for lines with and without the tin gene, respectively. Despite the large difference in tillering, there were only small differences in LAI, light interception throughout the season, and biomass. There were small differences in the proportional allocation of biomass, and the tin lines partitioned more of their biomass towards spikes at anthesis and stored more WSC in stems. Dry weight distribution varied with genetic background, but in general the tin gene increased leaf area ratio and root to shoot ratio but decreased specific leaf area. It is concluded that the tin gene may be advantageous under terminal drought. This would come from the reduced light interception prior to anthesis and thereby potential for greater transpiration during grain filling as well as a greater capacity for stem carbohydrate storage and remobilisation. These factors are consistent with a greater harvest index and kernel weight associated with lines containing the tin gene.