Effects of Temperature on Leaf Expansion in Sunflower
Effects of Temperature on Leaf Expansion in Sunflower
复制标题
温度对向日葵叶片展开的影响
DOI：
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发表时间：
1982
期刊：
影响因子：
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通讯作者：
J. Hindmarsh
中科院分区：
文献类型：
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作者：
H. Rawson;J. Hindmarsh
将五个商业向日葵栽培品种在三种温度制度（32/22 ° C、27/17 ° C和22/12 ° C）和15-h和11-h光周期下在橱柜中生长，并且随后展开5 - 15片叶。随着温度的升高（0.022叶天-1 °C-1）和日照长度的增加，叶片出现更快。单个叶片的面积线性增加的植物剖面，虽然最终每叶面积（Amax）随着温度的升高而下降，每个叶位的相对变化是相似的。品种保持其排名Amax跨温度，这些排名同意在以前的领域研究。在每个温度条件下，叶片的膨胀速率和膨胀持续时间都随叶位的增加而增加。随着温度的升高，叶片生长的时间缩短，变化为1.04天° C-1，但在所使用的光子通量密度（500 µ mol m-2 s-1，或约25%的全日照）下，膨胀率在最低温度下最大。膨胀率只有三分之一的实地研究在可比的温度，但持续时间是相似的。达到最大Amax的品种是通过更快的扩张速度，而不是通过更长的持续时间：只有一个品种不同的平均（20天）叶片扩张的持续时间。所有品种达到花分化逐步提前延长光周期从10到15小时，与最敏感的品种的变化是8天，最不敏感的5天。叶片出现的速度与这种敏感性。
Five commercial cultivars of sunflower were grown in cabinets at three temperature regimes, 32/22, 27/17 and 22/12°C, and with 15-h and 11-h photoperiods, and expansion of leaves 5-15 was followed. Leaves appeared faster with increasing temperature (0.022 leaves day-1 °C-1) and with increasing daylength. Areas of individual leaves increased linearly up the plant profile and, although final area per leaf (Amax) decreased with increasing temperature, the relative change was similar for each leaf position. Cultivars maintained their ranking for Amax across temperatures, and these rankings agreed with those in previous field studies. Within each temperature regime, both the expansion rate of leaves and the duration of expansion increased with leaf position. As temperature increased, leaves grew for shorter periods with a change of 1.04 days °C-1, but under the photon flux density used (500 µmol m-2 s-1, or about 25% full sunlight) expansion rates were greatest at the lowest temperature. Expansion rates were only one-third of those in field studies at comparable temperatures, but durations were similar. Cultivars that achieved the largest Amax did so via faster rates of expansion and not via longer durations: only one cultivar differed from the mean (20 days) duration of leaf expansion. All cultivars reached floral initiation progressively earlier with extension of photoperiod from 10 to 15 h, with the change for the most sensitive cultivars being 8 days and for the least sensitive 5 days. Rates of leaf emergence were linked with this sensitivity.