Gibberellins and Stem Growth as Related to Photoperiod in Silene armeria L.
Gibberellins and Stem Growth as Related to Photoperiod in Silene armeria L.
复制标题
DOI：
10.1104/pp.92.4.1094
复制
发表时间：
1989-04
期刊：
影响因子：
7.4
通讯作者：
M. Talón;J. Zeevaart
中科院分区：
文献类型：
--
作者：
M. Talón;J. Zeevaart
长日照植物蝇子草的茎生长和开花。通过暴露于至少3至6个长日（LD）诱导。茎生长在随后的短天数（SD）中继续，尽管速率降低。生长延缓剂四环素抑制LD诱导的茎伸长，但对开花无影响。这表明光周期控制蝇子草茎生长是由赤霉素（GA）介导的。本研究的目的是分析光周期的影响，内源GAs的水平和分布在蝇子草，并确定在这种植物的茎生长的光周期后效的性质。通过全扫描气相色谱-质谱联用（GC-MS）从蝇子草提取物中鉴定出GA（12）、GA（53）、GA（44）、GA（17）、GA（19）、GA（20）、GA（1）、GA（29）和GA（8），为早期13-羟基化途径的成员。所有这些GAs都存在于SD以及LD条件下的植物中。在SD条件下，GA（53）含量最高，转入LD条件下，GA（53）含量下降。与此相反，GA（19），GA（20）和GA（1）最初增加的植物转移到LD，然后下降。同样地，当Silene植物从LD返回到SD时，GA（53）增加，GA（19）、GA（20）和GA（1）减少，最终达到与在SD中保持的植物中发现的水平相似的水平。因此，在蝇子草的整个枝条中以及植物的各个部分中的GA水平的测量表明，光周期主要通过GA的转化率来调节GA代谢（53）。LD诱导的结果是，GA（1）在茎尖中积累到最高水平，从而导致茎伸长。此外，LD还增加了组织对GA的敏感性，这种效应可能是导致光周期后效应对蝇子草茎伸长的原因。
Stem growth and flowering in the long-day plant Silene armeria L. are induced by exposure to a minimum of 3 to 6 long days (LD). Stem growth continues in subsequent short days (SD), albeit at a reduced rate. The growth retardant tetcyclacis inhibited stem elongation induced by LD, but had no effect on flowering. This indicates that photoperiodic control of stem growth in Silene is mediated by gibberellins (GA). The objective of this study was to analyze the effects of photoperiod on the levels and distribution of endogenous GAs in Silene and to determine the nature of the photoperiodic after-effect on stem growth in this plant. The GAs identified in extracts from Silene by full-scan combined gas chromatography-mass spectrometry (GC-MS), GA(12), GA(53), GA(44), GA(17), GA(19), GA(20), GA(1), GA(29), and GA(8), are members of the early 13-hydroxylation pathway. All of these GAs were present in plants under SD as well as under LD conditions. The GA(53) level was highest in plants in SD, and decreased in plants transferred to LD conditions. By contrast, GA(19), GA(20), and GA(1) initially increased in plants transferred to LD, and then declined. Likewise, when Silene plants were returned from LD to SD, there was an increase in GA(53), and a decrease in GA(19), GA(20), and GA(1) which ultimately reached levels similar to those found in plants kept in SD. Thus, measurements of GA levels in whole shoots of Silene as well as in individual parts of the plant suggest that the photoperiod modulates GA metabolism mainly through the rate of conversion of GA(53). As a result of LD induction, GA(1) accumulates at its highest level in shoot tips which, in turn, results in stem elongation. In addition, LD also appear to increase the sensitivity of the tissue to GA, and this effect is presumably responsible for the photoperiodic after-effect on stem elongation in Silene.