【作者】 赵春明；

【导师】 王密侠；

【作者基本信息】 西北农林科技大学 ， 农业水土工程， 2010， 硕士

【摘要】 本文就亏水处理条件下梨枣树的生理响应机制进行了研究。主要研究了梨枣树各生育阶段的耗水规律、亏水条件下梨枣树的生理生态反应以及亏水对梨枣品质的影响,按梨枣树的生理生长特性将梨枣树生育阶段划分为五个：越冬休眠期、萌芽展叶期、开花坐果期、果实膨大期和果实成熟期。试验在西北农林科技大学节水灌溉试验站的大型日光温室内进行,试验设置5个处理,2个重复。取得了如下研究结果：(1)与对照相比,各阶段亏水处理均能有效减缓土壤水分的消耗。各亏水处理表层土壤水分的变化速率要小于对照,且各处理灌水前期水分变化速率要高于灌水后期。不同处理的土壤水分变化主要集中在0～80cm土层,地表至40cm深的土壤水分变化比较剧烈,是水分的速变层。各处理不同土壤深度的水分变化规律具有相似的规律,但随着土壤深度的增加土壤水分变化幅度有所减小。各处理不同时期的变化规律也具有较好的相似性。(2)水分调控对梨枣树的茎液流的日变化有较明显的影响。在前人研究梨枣树茎液流变化和同时期蒸腾速率之间的关系的基础上,对相对于蒸腾速率延后0.5h及1h的茎液流进行了研究,结果表明：茎液流的变化与蒸腾速率的变化之间有一定的时滞性,梨枣树蒸腾速率与延后1小时的茎液流的相关性要好于同时期的茎液流与蒸腾速率的相关性,这可能是由于水分在植物体内运输需要一定时间所致；各处理梨枣树茎液流的日变化规律均呈抛物线型,在持续水分胁迫下,梨枣树茎液流出现明显波动,亏水处理下梨枣树茎液流比充分供水条件下梨枣树茎液流有所减少；各个生育时期梨枣树茎液流量大小有所不同,在萌芽展叶期和果实膨大期茎液流量较大,梨枣树的开花坐果期、果实膨大期和果实成熟期梨枣树茎液流之和占到整个生育时期茎液流总量的75%左右,说明这三个时期是梨枣树用水的关键时期；分析了充分灌水条件下梨枣树茎液流与太阳辐射、日平均温度的关系,梨枣树茎液流与太阳辐射和日平均温度具有较好的相关性,与日平均温度的相关系数达到了0.7235,与太阳辐射的相关性系数为0.5594。(3)地温变化是太阳辐射量、大气温度及土壤含水量共同作用的结果。不同亏水处理下的地温变化规律是一致的,随着土壤深度的增加,温度有所减小,地温变化的幅度也逐渐平缓。夏季充分灌水条件下地温要低于亏水处理条件下,且充分灌水条件下地温变化幅度要小,而冬季充分灌水条件下,地温明显高于亏水处理,说明灌水可调节地温。研究结果表明夏季地温的变化与太阳辐射量显著正相关,与土壤含水量呈负相关。(4)亏水处理对梨枣树的产量和品质均有一定的影响,对照处理亩产1400Kg左右,处理3的产量降幅最大,而处理2和处理5的产量与对照相差不多,这说明梨枣树的开花坐果期和果实膨大期对水分的敏感程度较高；亏水处理并不是对所有的品质指标均起到提高和改善的作用,亏水处理对梨枣的品质的影响主要表现在对维生素C、可溶性固形物、可溶性糖分和糖酸比等品质指标的影响上。亏水处理能显著提高果实的硬度、维生素C、可溶性固形物、可溶性糖分和糖酸比且达到极显著水平(α=0.01),试验数据表明各处理均可使果实可溶糖含量提高,与对照相比T2提高37.5%,T3、T4、T5分别提高了18.1%、26.1%和9.5%,使得果实口感更好达到了以水调控品质的效果。处理2能较大程度上减小果实的单果重、体积和果实有机酸的含量,T2～T5处理下梨枣单果重分别较对照下降了10.6%、8.4%、8.0%、3.7%。充分灌水条件下梨枣的平均体积为25.20cm3,而T2处理为20.15 cm3,比充分灌水条件下减小了20%,减小幅度最大。但是亏水处理对梨枣果实的含水率和可溶性蛋白的含量影响不是很大。(5)亏水处理对各处理的梨枣树树叶单叶WUE有不同的影响,轻度亏水处理的梨枣树树叶WUE要高于中度亏水处理的。在部分时间段内,干旱胁迫能提高梨枣树叶片的水分利用效率。亏水处理的梨枣树新梢生长量均小于对照,亏水处理能明显的抑制梨枣树的新梢生长,这将有利于树体以后的生殖生长。更多还原

【Abstract】 The paper studied physiological mechanism to pear-jujube tree under RDI,The experiment was conducted in the laboratory of Northwest A&F University, shanxi province.According to growth characteristic of pear-jujube tree, five growth stages was use for deficit stages of the experiment as follows:Winter dormancy, leaf stage, flowering and fruit setting, fruit enlargement and fruit maturity, There were five treatments.The deficit of single and whole growth stages was used. The research fruit wan as follows:(1)The relationship between evaporation and surface soil water content is linear 90% root of pear-jujube tree concentrated on the 0-80cm soil layer, which is the main layer for tree absorb water and nutrients.So this experiment designed 0-80cm soil layer for the scheming humid layer. The variation of soil water content under different treatments is same. The vary of soil water content change is smaller than fully irrigation. It proves that RDI could save water.(2)RDI had significant effects on the sap flow of pear-jujube tree. This experiment reference to the previous experiment on the relationship between transpiration rate and sap flow found that:the change of sap flow behind the change of transpiration rate about 1 hour.This because water transport in the plant need time.this experiment show that:the variation of sap flows in the peer-jujube trees during the day and the night are obviously different.During the day they exhibit an irregular inverted-U relationship and obviously fluctuate at noon.The total amount of sap flow are different in every grow stages. Based on the test data can be obtained that the number of sap flow on stage of bud leaf expansion, stage of fruit enlargement and ripe stage can account to 75% for the whole growing period. The study indicates that, the variation of sap flows is a combined result of solar radiation and daily average temperature. The variation of sap flow linearly with solar radiation and daily average temperature, the coefficient is 0.7235 and 0.5594.(3)The variation of geotemperature in green house is a combined result of solar radiation, outside air temperature and soil water content. There are significant correlation between geotemperature and solar radiation and correlates negatively linearly with soil water content. The variation of geotemperature under different treatments is same. With the increase of depth the geotemperature is reduce. The geotemperature under fully irrigation below than RDI in summer.(4)The results indicate that:RDI had impact on quality and yield.The yield is biggest for fully irrigation which is 1400kg/a,Expect treatment 3,other treatments yield are not reduce greatly compact with the controlled treatment. But the treatment that suffered serious water deficit during flowering decreased average fruit weight, fruit volume and Vc. The decrease of T2-T5 average fruit weight 10.6%、8.4%、8.0%、3.7% respectively. The volume of fruit under fully irrigation is 25.20cm3 while it is 20.15 cm3 under 2 treatment,Compared with fully irrigation,the volume was deceased 20%.The influence to the fruit water content and soluble protein content for all the treatments are similar. All the treatments could elevated the content of Vc, soluble solid matter and sugar.The results indicate that all the treatments elevated the content of sugar about 37.5%,18.1%,26.1% and 9.5%respectively compact with the controlled treatment. It indicates that RDI could elevate the quality of fruit.(5)RDI have different influence to the leaf water use efficiency(WUE). The WUE under lightly is high then moderately irrigation. In some grow stages RDI could increasing WUE. According to the study showed that:different water regulated controlled on different growth period had inhibition role to plant branch.更多还原