The effects of ploidy and a phenotype conferring a high water-soluble carbohydrate concentration on carbohydrate accumulation, nutritive value and morphology of perennial ryegrass (Lolium perenne L.)
The effects of ploidy and a phenotype conferring a high water-soluble carbohydrate concentration on carbohydrate accumulation, nutritive value and morphology of perennial ryegrass (Lolium perenne L.)
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倍性和表型赋予高水溶性碳水化合物浓度对多年生黑麦草（Lolium perenne L.）碳水化合物积累、营养价值和形态的影响
DOI：
10.1017/s0021859600008480
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发表时间：
2001
期刊：
影响因子：
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通讯作者：
R. N. Oram
中科院分区：
文献类型：
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作者：
Kevin F. Smith;R. Simpson;R. Culvenor;M. Humphreys;M. Prud'homme;R. N. Oram
四倍体或二倍体基因型的使用赋予高的水溶性碳水化合物浓度的基因是两种机制，以提高多年生黑麦草的营养价值。本试验比较了6个多年生黑麦草品种在受控环境条件下生长的56天龄植株的形态、营养价值和水溶性碳水化合物（WSC）浓度的日变化。这些品种中有三个是二倍体（Melle，Aurora和Cariad），三个是四倍体（Meltra，Prospero和AberOnyx），它们来自各自的二倍体品种。两个二倍体品种（Cariad和Aurora）以前被选为高浓度的水溶性碳水化合物。四倍体品种比二倍体（平均83）有更少（平均59），更大的分蘖。然而，除Melle和Meltra外，二倍体品种的干物质产量与其四倍体衍生物没有显着差异。四倍体对WSC浓度的影响取决于品种的遗传背景。Melle先前未被选择用于增加WSC，其WSC浓度显著低于其四倍体衍生物Meltra。然而，四倍体并没有进一步增加WSC浓度在那些品种先前选择的高WSC浓度。在整个光周期中，Aurora和Melle叶片中的WSC浓度上升了65-70 g/kg，这表明这些品种的总WSC浓度的差异不是由于Aurora固定的碳量增加，而是由于生长和发育过程中碳分配的差异。本实验表明，四倍体是不利于提高多年生黑麦草的WSC浓度时，施加在两个二倍体品种，具有增加WSC积累的遗传潜力。然而，四倍体显着增加的WSC浓度和暗示的营养价值的品种来自一个多年生黑麦草品种与标准WSC浓度。
Tetraploidy or the use of diploid genotypes with genes conferring high water-soluble carbohydrate concentrations are two mechanisms to increase the nutritive value of perennial ryegrass. This experiment compared the morphology, nutritive value and diurnal variation in water-soluble carbohydrate (WSC) concentrations of 56-day-old plants from six perennial ryegrass cultivars grown under controlled environment conditions. Three of these cultivars were diploid (Melle, Aurora and Cariad) and three were tetraploids (Meltra, Prospero and AberOnyx) which had been derived from the respective diploid cultivars. Two of the diploid cultivars (Cariad and Aurora) had previously been selected for high concentrations of water-soluble carbohydrates. The tetraploid cultivars had fewer (mean 59), larger tillers than the diploids (mean 83). However, with the exception of Melle and Meltra the dry matter yield of the diploid cultivars was not significantly different from their tetraploid derivatives. The effect of tetraploidy on WSC concentrations was dependent on the genetic background of the cultivars. Melle, which had not been previously selected for increased WSC, had a significantly lower WSC concentration than its tetraploid derivative, Meltra. However, tetraploidy did not further increase the WSC concentration in those cultivars previously selected for high WSC concentrations. WSC concentrations in the leaf of both Aurora and Melle rose by 65–70 g/kg throughout the photoperiod, suggesting that differences in the total WSC concentration of these cultivars were not due to any increase in the amount of carbon fixed by Aurora but rather due to differences in the allocation of carbon during growth and development. This experiment demonstrated that tetraploidy was not beneficial in improving the WSC concentration of perennial ryegrass when imposed on two diploid cultivars which had the genetic potential for increased WSC accumulation. However, tetraploidy significantly increased the WSC concentration and by implication the nutritive value of a cultivar derived from a perennial ryegrass cultivar with standard WSC concentrations.