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On the Loess Plateau of China, a dry soil layer may form due to excess transpiration, leading to degradation of black locust(Robinia pseudoacacia) stands. In order to better manage projects involving black locust, this study was intended to investigate the response of black locust transpiration rate to soil water availability as affected by meteorological factors using two representative soils(loamy clay and sandy loam) on the Loess Plateau. Four soil water contents were maintained for black locust seedlings grown in pots initially outdoors and then in a climate-controlled chamber, by either drying or irrigating the pots. In both environments, daily transpiration rates were related by a power function to air temperature and by a logistic function to reference evapotranspiration(ET0). Transpiration rates were more susceptible to changes in the meteorological conditions in the sandy loam than in the loamy clay soil. The transpiration rate in the well-watered treatment was greater for black locust grown in the sandy loam than in the loamy clay soil. Normalized transpiration rates were unaffected by ET0 until a critical value of soil water content(θc) was attained; the θc value decreased significantly for the loamy clay soil but increased significantly for the sandy loam soil when ET0 increased. These suggested that the effect of the meteorological condition on the transpiration characteristics of black locust was dependent on soil texture. 相似文献
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不同品种冬小麦冠层温度与抗旱性和水分利用效率的关系研究 总被引:4,自引:0,他引:4
本试验利用红外测温仪于2006-2007年在甘肃陇东旱塬,测定了40个冬小麦品种灌浆期冠层温度,研究了冠层温度与抗旱指教和水分利用效率之间的关系,研究结果表明,不同水分条件下40个冬小麦品种灌浆期冠层温度、抗旱指数和水分利用效率差异均达到了极显著水平,水分利用效率和冠层温度与抗旱指数之间相关性分析表明,抗旱指数与水分利用效率之间存在显著的正相关关系(r=0.769***);抗旱指数与冠层温度呈极显著负相关(r=-0.772***),7个抗旱性强的品种其冠层温度较40个品种(系)平均值低1℃,11个抗旱性弱的品种则高出加个品种(系)平均值0.68℃,说明冠层温度能够反映品种抗旱性. 相似文献
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干旱高温胁迫对小麦生长及木聚糖含量的影响 总被引:2,自引:0,他引:2
选取两个水分处理(拔节期开始,95%和40%田间持水量)、两个温度水平(孕穗期开始,昼/夜温度分别为25℃/15℃和35℃/25℃)和两个春小麦品种(Superb和AC Crystal)在温室条件下进行试验,分析了小麦不同生育期生长及开花期叶片气体交换参数和成熟期产量及木聚糖含量的变化。结果表明:高温处理下Superb成熟时间比适温处理下提前20天,AC Crystal提前21天;孕穗期高温干旱两种胁迫均显著降低了小麦的株高,并且两种因子结合后产生的作用最强,其中,Superb的株高降低了16.7%,AC Crystal降低了30.6%;两个小麦品种生育后期以AC Crystal的分蘖数较多,孕穗期温度水分适宜条件下AC Crystal分蘖数比Superb高18.7%,但其对温度敏感性较强。高温干旱显著降低了叶片气体交换参数的值,Superb在干旱高温条件下Pn比其在温度水分适宜条件下降低了68.9%。高温增加了小麦籽粒木聚糖的含量,特别是水溶性木聚糖(WEAX),干旱环境下高温处理使得Superb的WEAX升高了49%;木聚糖含量与叶片各气体交换指标参数和产量之间呈显著的负相关关系。 相似文献
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