【作者】 范雯雯；

【导师】 林同保；

【作者基本信息】 河南农业大学 ， 作物栽培学与耕作学， 2010， 硕士

【摘要】 试验于2008-2009年在河南农业大学科教园区全自动防雨棚下进行,采用盆栽试验,较系统地研究了不同土壤肥力条件下,不同生育时期干旱及复水对冬小麦生长发育、光合特性、保护酶系统、膜脂过氧化产物、渗透调节物质、灌浆速率、产量和水分利用效率等几个方面的影响。主要结果如下:1、不同土壤肥力下旱后复水对冬小麦株高和干物质积累的影响整体上来看,返青期适应干旱的能力大于拔节期,中度干旱受伤害的程度小于重度干旱。复水后,冬小麦株高、根、冠干物质积累量均超过了其相应的干旱对照,表现出了补偿或超补偿效应,返青期干旱拔节期复水的补偿效应大于拔节期干旱孕穗期复水处理;中度干旱的补偿效应大于重度干旱;高肥力土壤条件下的补偿效应>中肥力>低肥力。恢复供水后同化物分配到冠部的比例增大,使根冠比下降。2、不同土壤肥力下旱后复水对冬小麦叶绿素含量和光合速率的影响无论是返青期干旱处理还是拔节期干旱处理,同一土壤肥力条件下,冬小麦叶片叶绿素含量和光合速率均随干旱程度的增加而降低,复水后,叶绿素含量和光合速率均超过了其相应的干旱对照,表现出了补偿或超补偿效应,花后光合速率则表现为返青期干旱处理与其相应的湿润对照之间差异不显著,甚至超过了其相应的湿润对照,拔节期干旱处理则是在光合速率达到最大值之前与其相应的湿润对照之间差异不显著,最大值之后降低的幅度大于其相应的湿润对照,不利于后期籽粒灌浆。同一水分条件下,叶绿素含量和光合速率随肥力的降低而降低。3、不同土壤肥力下旱后复水对冬小麦SOD活性和MDA含量的影响同一土壤肥力条件下,SOD活性、MDA含量随干旱程度的增加而增加,但在低肥力条件下,SOD活性为中度干旱对照>重度干旱对照>湿润对照;复水20天时,除拔节期重度干旱的MDA含量未达到或接近其相应的湿润对照水平外,其它处理的SOD活性、MDA含量均达到或接近其相应的湿润对照水平,表现出了补偿或超补偿效应;同一水分条件下,SOD活性随肥力的降低而降低;在中度干旱条件下,MDA含量随肥力的降低而增加、在重度干旱条件下则表现为:中肥力>高肥力>低肥力。4、不同土壤肥力下旱后复水对冬小麦渗透调节物质的影响同一土壤肥力条件下,随干旱程度的增加,脯氨酸、可溶性糖含量增加、可溶性蛋白含量降低。复水20天时,脯氨酸、可溶性糖含量达到或接近其相应的湿润对照水平,而中肥力和低肥力条件下返青期重度干旱处理和拔节期干旱处理的可溶性蛋白含量却没有恢复到其相应的湿润对照水平。同一水分条件下,脯氨酸、可溶性糖、可溶性蛋白含量随土壤肥力的提高而增加。5、不同土壤肥力下旱后复水对冬小麦灌浆速率的影响同一土壤肥力下,灌浆速率达到最大值之前,灌浆速率随干旱程度的增加而增加,最大值之后,灌浆速率随干旱程度的增加而降低,由于干旱和土壤养分缺乏,低肥力中度干旱对照和重度干旱对照在花后20天达到了最大值,其它处理在花后25天达到最大值。返青期干旱处理在灌浆后期下降的幅度小于其相应的湿润对照,灌浆期持续时间长,表现出了超补偿效应,拔节期干旱处理灌浆最大值之前与其相应的湿润对照之间差异不显著,最大值之后,下降的幅度大于其相应的湿润对照,灌浆持续时间比其相应的湿润对照短。6、不同土壤肥力下旱后复水对冬小麦产量及水分利用效率(WUE)的影响同一土壤肥力条件下,生物学产量、籽粒产量、穗数、穗粒数和千粒重随干旱程度的增加而降低。返青期干旱处理与其相应的湿润对照间生物学产量差异显著,而与其相应的湿润对照间籽粒产量、产量构成三因素差异不显著。拔节期干旱处理与其相应的湿润对照间生物学产量、籽粒产量、产量构成三因素差异均显著。同一水分条件下,不同土壤肥力间生物学产量、籽粒产量、产量构成三因素差异均显著。高肥力土壤条件下,中度干旱对照的WUE最高,而与重度干旱对照、返青期干旱处理间差异不显著,在中肥力和低肥力条件下,均是重度干旱对照的WUE最高,且与其它处理间差异显著。同一水分条件下,冬小麦WUE随土壤肥力的降低而降低,不同肥力间差异显著。说明提高土壤肥力有利于旱后冬小麦WUE的提高,但拔节期干旱后复水对冬小麦WUE的提高作用不明显。更多还原

【Abstract】 The experiment was carried out under the automatic control canopy at the Henan Agricultural University Science and Education Park Area in 2008-2009. We systematically studied the effects of drought and rewatering on growth, photosynthetic characteristics, protective enzyme system, lipid peroxidation product, osmoregulatory molecules, filling rate, yield and water use efficiency of winter wheat under different conditions of growth and fertility. The main conclusions were as follows:1, Effect of drought and rewatering on growth of winter wheat under different fertility conditionsOn the whole, green returned stage adapted to drought stress was stronger than jointing stage, the effect of serious drought stress was stronger than moderate drought stress. Plant height, dry matter accumulation quantity of root and shoot of winter wheat exceeded its corresponding drought contrast after rewatering, presented compensatory or ultra compensatory effect, the compensation effect of drought at green returned stage was stronger than jointing stage; moderate drought stress was stronger than serious drought stress; high fertility>medium>low. The photosynthate allocated to increase the proportion of shoot after rewatering, and maked root-shoot radio decrease.2, Effect of drought and rewatering on chlorophyll content and Photosynthetic rate of winter wheat under different conditions of fertilityChlorophyll content and Photosynthetic rate of winter wheat decreased with the serious of drought levels under the same fertility condition, and decreased with the reduction of fertilizer levels under the same water condition whether drought stress treatment at green returned stage or jointing stage. Chlorophyll content and Photosynthetic rate of winter wheat exceeded its corresponding drought contrast after rewatering, presented compensatory or ultra compensatory effect, photosynthetic rate of post-anthesis was no significant difference between drought stress treatment at green returned stage and its corresponding wet comparison, even more than the corresponding wet comparison; and no significant difference between drought stress treatment at jointing stage and its corresponding wet comparison before maximum, then significant difference after maximum, it was not conducive to grain filling at late stage.3, Effect of drought and rewatering on SOD and MDA of winter wheat under different fertility conditionsSOD activity and MDA content of winter wheat increased with the serious of drought levels under the same fertility condition, but at the low fertility condition, SOD activity was moderate drought stress comparison > serious drought stress comparison > wet comparison; SOD activity and MDA content of winter wheat reached or nearly its wet comparison levels except of MDA content of serious drought stress at jointing stage after rewatering 20 days, presented compensatory or ultra compensatory effect; SOD activity decreased with the reduction of fertilizer levels under the same water condition; MDA content increased with the reduction of fertilizer under the moderate drought stress; medium fertility >high > low under the serious drought stress.4, Effect of drought and rewatering on osmotic adjustment of winter wheat under different fertility conditionsProline and soluble sugar content of winter wheat increased and soluble protein content decreased with the serious of drought levels under the same fertility condition, and increased with the reduction of fertilizer levels under the same water condition. After rewatering 20 days,proline,soluble sugar and soluble protein content of winter wheat reached or nearly its wet comparison levels except of soluble protein content content at jointing stage and green returned stage under medium and low fertility condition. proline,soluble sugar and soluble protein content increased with the increase of soil fertility under the same water condition.5, Effect of drought and rewatering on filling rate of winter wheat under different fertility conditionsFilling rate of winter wheat increased before reaching maximum and decreased after the maximum with the serious of drought levels under the same fertility condition, moderate drought stress comparison under low fertility condition and serious drought stress comparison reached maximum after 20 days after flowering, and the other treatments reached maximum after 25 days after flowering. Filling rate of drought stress treatments at green returned stage the decrease in the late filling stage was lower than the corresponding wet comparison,which presented ultra compensatory effect, filling rate was not significant difference between drought stress treatments at jointing stage and its corresponding wet comparison before maximum, then significant difference after maximum, it was not conducive to increase yield.6, Effect of drought and rewatering on grain yield and WUE of winter wheat under different fertility conditionsBiological yield, grain yield, the effective numbers of ears, the grain numbers of each ear and the 1000 grain weight of winter wheat decreased with the serious of drought levels under the same fertility condition. Biological yield was significant difference between drought stress treatments at green returned stage and its corresponding wet comparison, grain yield and three components of yield were not significant difference, and significant difference between drought stress treatments at jointing stage and its corresponding wet comparison. They were significant difference with the reduction of fertilizer levels under the same water condition.Moderate drought stress comparison of water use efficiency (WUE) under the high fertility condition was the highest, and no significant difference with serious drought stress comparison and drought stress treatments at green returned stage, serious drought stress comparison of WUE was high under the medium and low fertility condition, and no significant difference with other treatments. WUE decreased with the reduction of fertilizer levels under the same water condition. The results suggested that properly increasing fertilizer amount is conducive to recovery and increase water use efficiency of winter wheat.更多还原