土壤湿度对冬小麦主要形态特征的影响效应研究

确定土壤水分对冬小麦株高、叶面积指数(LAI)和单茎干物质重量等主要形态特征参量的影响关系，是品种选育、节水栽培措施改进及其建立相关作物监测评估模型的重要基础。为了探讨土壤湿度对冬小麦主要形态特征的影响效应，以‘皖麦52’为试验材料，针对冬小麦返青、拔节和抽穗期，利用遮雨棚进行3年田间水分控制试验，采用相关分析和回归统计等方法，探讨不同生育期土壤湿度变化对冬小麦株高、LAI和单茎干物质影响效应。结果表明：返青、拔节和抽穗期土壤湿度变化均会引起株高、LAI和单茎干重发生变化，以拔节期土壤湿度对抽穗期株高和拔节到抽穗期土壤湿度对LAI和单茎干重的影响最为显著。土壤湿度对各形态特征参量的影响可以用一元一次或一元二次回归方程来表达。主要形态特征参量实现适宜或最优量值的适宜土壤相对湿度指标为70%左右。不同生育期发生干旱均会导致株高、LAI和单茎干重发生不同程度的降低或减少，其影响具有后延性，且干旱发生时间越早，后延性越长。所得结论可为品种选育和节水栽培措施改进工作提供参考。各效应方程，可用于监测评估土壤湿度变化对株高、LAI和单茎干重的定量影响。

Influence of Soil Moisture on Main Morphological Characteristics of Winter Wheat

Determining the influence of soil moisture on the main morphological parameters like plant height, leaf area index (LAI) and dry matter weight of seedling of winter wheat is an important basis of variety breeding, improvement of water saving cultivation measures and establishment of relevant crop monitoring and evaluation model. To discuss the influence of soil moisture on the main morphological characteristics of winter wheat, the field moisture control experiment was developed in 3 years based on the wheat varieties ‘Wanmai 52’. The green stage, jointing stage and heading stage were studied and canopy was used to control the field water in the experiment. The correlation analysis, regression statistics and so on were used to discuss the influence of soil moisture change on plant height, leaf area index (LAI) and dry matter weight of seedling of winter wheat in different growth period. Results showed that: soil moisture change in the green stage, jointing stage and heading stage would all cause the change of plant height, LAI and dry matter weight of seedling. Especially, the soil moisture in jointing stage had the most significant influence on the plant height in heading stage; soil moisture from jointing stage to heading stage had a most significant dry matter weight of seedling. The influence of soil moisture on the main morphological parameters could be expressed with linear regression equation with one unknown or quadratic regression equation in one unknown. The appropriate relative soil moisture index at which the main morphological parameters could reach their appropriate value or optimal value was around 70%. Drought in different growth period would all cause the reduction of plant height, LAI and dry matter weight of seedling to some extent. The reduction would persist, what’s more, the earlier the drought occurred, the longer the reduction persisted. The results achieved in the research could provide reference for variety breeding and improvement of water saving cultivation measures. The equation established in the research could be used to monitor and evaluate the quantitative influence of soil moisture change on plant height, LAI and dry matter weight of seedling.