SH矮砧苹果幼树滴灌条件下需水特性与生理指标响应研究

发布时间：2018-08-29 07:59

【摘要】：我国面临的水资源缺乏的问题日益突出,山西省地处黄土高原东部,是全国水资源最为匮乏的省份之一。滴灌技术是一种现代化的节水灌溉技术,与喷灌相比水分利用效率提高了30%-40%,比传统灌溉相比水分利用效率提高了70%-80%。SH矮砧是山西省农科院果树所选育出的适应我国自然条件的苹果矮化砧木。苹果生产对滴灌上、下限的要求,因树种、树龄、当地气候状况和土壤结构等因素而发生改变,研究确定SH矮砧苹果幼树滴灌条件下适宜的灌水上限及需水特性,将有利于制定合理的灌溉制度,有助于滴灌在黄土高原干旱半干旱地区SH苹果园的进一步推广。本论文设置滴灌条件下以60%田间持水量为灌水下限,分别设置不同的灌水上限70%(T1)、80%(T2)、90%(T3)、100%田间持水量(T4),以及设置对照试验地面灌溉,对SH矮砧苹果幼树2016年4—10月土壤含水率、棵间蒸发量、茎流速率、清晨叶片水势、新梢生长量、树干直径、叶片光合特性、叶片水分利用效率数据测定以及对气象要素数据进行分析整理。通过试验数据分析了滴灌条件下土壤水分分布特征、运用茎流计-微型蒸渗仪法和水量平衡法对比计算得出了SH矮砧苹果树的需水特性、得出了各项生理指标的变化特性及影响因素、基于主成分分析法综合确定得出适宜SH矮砧苹果幼树的灌水上限。得出以下主要结论:1、滴灌条件下SH矮砧苹果幼树土壤水分分布特征研究(1)滴灌条件下不同灌水上限各处理计划湿润层土壤平均体积含水率均在试验设置的上下限范围内波动,总体来说随着灌水上限的增大,土壤含水率达到灌水下限的时间就越长,灌水次数也就越少。(2)不同灌水上限土壤水分增量在垂向及径向上的分布特征基本一致,土壤含水率增量在垂向及径向的变化符合指数函数,土壤含水率增量与土层深度、径向距离呈现负相关关系。不同灌水上限土壤水分二维分布特征为:以滴灌管滴头为中心,向四周逐渐减小。灌水上限越大,同一位置处水分增量越大,土壤水分的垂向、径向推进距离越远。2、滴灌条件下SH矮砧苹果幼树需水特性研究由茎流计-微型蒸渗仪法和水量平衡法计算得到全生育期苹果幼树需水特性大小关系基本一致,需水量总量大小关系T1T2T3T4CK,由此计算得到苹果树全生育期日需水强度T1T2T3T4CK,计算结果表明随着灌水上限的升高,苹果树的需水总量逐渐增大,各处理不同月份需水模数基本上呈现7月8月6月5月9月4月10月的趋势。两种方法计算结果日需水强度平均相对误差相对较小,所以两种方法均可为计算试验地果树全生育期需水量与日均需水强度提供指导和帮助。3、滴灌条件下SH矮砧苹果幼树生理指标响应研究(1)不同灌水上限滴灌处理与地面灌溉处理清晨叶片水势的变化趋势基本一致,在不同时段,全生育期清晨叶片水势平均值T4T3CKT2T1,不同处理之间差异达到了显著水平(P0.05),表明不同的灌水上限对清晨叶片水势的影响显著。(2)不同灌水上限滴灌处理新梢生长量、树干直径指标变化趋势基本一致,随着时间的延续逐渐变大。综合对比分析五种处理水平,5~10月份新梢累计增长量CKT3T4T2T1,树干直径累计增长量总体趋势表现为T3T4CKT2T1,新梢生长量、树干直径指标不同处理之间差异达到了显著水平(P0.05)。(3)不同滴灌处理苹果树新梢生长量、树干直径基本都符合Logistic方程,各个处理与Logistic方程拟合程度优良。模型预测值与实测值之间有一定的差距,但误差均较小,说明模型准确性较高,可以很好的预测果树的生长动态。Logistic生长模型可以很好的预测果树的新梢生长长度及树干直径大小以及它们的生长变化趋势。(4)不同灌水上限条件下叶片光合特性指标叶片净光合速率(Pn)、气孔导度(Cond)、蒸腾速率(Tr)、胞间CO2浓度(Ci)、叶片水分利用效率(WUE)变化趋势类似。将试验期内各处理光合特性4项指标进行相关性分析,得出:苹果树Pn与Ci呈现极显著负相关关系;Cond与Ci和Tr呈现极显著正相关关系;Ci与Tr呈现极显著正相关关系。不同处理间叶片Pn差异显著,综合比较5种处理水平,90%田持的灌水上限WUE最高。4、基于主成分分析法确定SH矮砧苹果幼树的适宜灌水上限基于主成分分析方法提取得到3个主成分因子,分别表征果树的新梢生长状况与光合特性指标、果树的土壤水分指标、果树的树干直径生长指标。综合主成分得分排名T3T4CKT2T1。说明综合考虑了果树的清晨叶片水势、生长状况、光合特性指标以及水分利用效率之后,在当地的气候条件下,综合比较5种处理水平,T3处理对试验区SH矮砧苹果幼树生长最为有利。故得出:在试验区内,滴灌条件下,当灌水下限为60%田间持水率时,灌水上限为90%田间持水率更适宜试验区SH矮砧苹果幼树的生长。
[Abstract]:Shanxi Province is located in the eastern part of the Loess Plateau. Drip irrigation is a modern water-saving irrigation technology. Compared with sprinkler irrigation, water use efficiency is increased by 30% - 40%, 70% - 80% higher than traditional irrigation. The Apple Dwarf rootstock selected by the fruit tree of Shanxi Academy of Agricultural Sciences is adapted to the natural conditions of our country.The requirement of apple production on the upper and lower limit of drip irrigation will be changed because of the tree species, tree age, local climate and soil structure. In this paper, under the condition of drip irrigation, the field water holding capacity of 60% was set as the irrigation water limit, and the different irrigation water limits of 70% (T1), 80% (T2), 90% (T3), 100% field water holding capacity (T4) were set respectively. Soil water content, inter-tree evaporation, stem flow rate, early morning leaf water potential, shoot growth, trunk diameter, leaf photosynthetic characteristics, leaf water use efficiency and meteorological data of young apple trees with SH dwarf rootstock from April to October 2016 were analyzed. The water requirement characteristics of SH dwarf rootstock apple trees were obtained by comparing and calculating the water requirement characteristics of SH dwarf rootstock apple trees with the stem flow meter-micro-infiltration meter method and the water balance method. Variation characteristics and influencing factors of physiological indexes were obtained. Based on the principal component analysis method, the suitable irrigation water limit of SH dwarf apple young trees was determined. Distribution characteristics of soil moisture in young apple trees under drip irrigation (1) Average volumetric water content of moist soil fluctuated within the upper and lower limits set by the experiment under different irrigation water caps. Generally speaking, with the increase of irrigation water caps, the longer the soil water content reached the irrigation water limit and the fewer irrigation times. The vertical and radial distributions of soil moisture increments in different irrigation water caps were basically consistent with those in the same irrigation water cap, and the vertical and radial variations of soil moisture increments were in accordance with exponential functions, and the soil moisture increments were negatively correlated with soil depth and radial distance. The larger the irrigation water limit, the greater the water increment at the same location, the farther the vertical and radial advance distance of soil moisture. 2. The water requirement characteristics of young apple trees with SH dwarf rootstock under drip irrigation were calculated by stem flow meter-micro-osmosis meter and water balance method, and the relationship between the water requirement characteristics of young apple trees during the whole growth period was basically the same. The daily water requirement intensity of apple trees during the whole growth period was calculated. The results showed that the total water requirement of apple trees increased gradually with the increase of irrigation water limit, and the water requirement modulus of different months showed the trend of July, June, May, September and October. The average relative error of daily water requirement intensity is relatively small, so the two methods can provide guidance and help for calculating the water requirement and daily water requirement intensity of fruit trees in the whole growth period. 3. Response of physiological indexes of young apple trees on SH dwarf rootstock under drip irrigation condition (1) Change of leaf water potential under different irrigation water limit drip irrigation treatment and surface irrigation treatment in the early morning The average leaf water potential T4T3CKT2T1 in the early morning of the whole growth period reached a significant level (P 0.05), indicating that different irrigation water limits had a significant effect on leaf water potential in the early morning. (2) The growth of new shoots and the change trend of trunk diameter index were basically the same under different irrigation water limits. Comparing and analyzing the five treatments, the cumulative increment of new shoot CKT3T4T2T1 and trunk diameter of apple trees from May to October showed a general trend of T3T4CKT2T1. The difference of new shoot growth and trunk diameter between different treatments reached a significant level (P 0.05). The length and diameter of tree trunk accorded with Logistic equation basically, and each treatment fitted well with Logistic equation. There was a certain gap between the predicted value and the measured value, but the error was small, indicating that the model had high accuracy and could well predict the growth dynamics of fruit trees. (4) Under different irrigation water limitations, the photosynthetic characteristics of leaves, such as net photosynthetic rate (Pn), stomatal conductance (Cond), transpiration rate (Tr), intercellular CO2 concentration (Ci) and water use efficiency (WUE), were similar. Correlation analysis showed that: apple tree Pn and CI showed very significant negative correlation; Cond and CI and Tr showed very significant positive correlation; Ci and Tr showed very significant positive correlation. Based on the principal component analysis method, three principal component factors were extracted to characterize the growth of shoots and photosynthetic characteristics of fruit trees, soil moisture index of fruit trees, and diameter growth index of fruit trees. After comparing the growth status, photosynthetic characteristics and water use efficiency under local climate conditions, T3 treatment was the most favorable for the growth of young trees of SH dwarf rootstock apples in the experimental area. The growth of SH Dwarf Rootstocks and apple saplings in the trial area.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S661.1

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