【作者】 王景伟；

【导师】 史振声；

【作者基本信息】 沈阳农业大学 ， 作物学， 2014， 博士

【摘要】 干旱是影响作物生长发育最主要的生态境因子,也是对作物产量最重要的限制因子之一。阐明水分亏缺对芸豆生长发育及产量的影响对于丰富作物干旱胁迫研究,解决本地区芸豆生产实际问题具有重要的理论和现实意义。本试验以奶花芸豆为研究对象,于2012年和2013年在黑龙江八一农垦大学实验场进行。采用不同浓度PEG-6000溶液模拟干旱,测定了种子萌发、生理指标的变化。通过人工控水的盆栽试验研究了不同程度、不同时期、不同时间干旱胁迫及复水对奶花芸豆形态、生理和产量的影响,建立了奶花芸豆干物质积累的动态模型。同时,利用烯效唑进行拌种处理的方法,研究其对干旱的调控作用。主要研究结果如下：1.利用PEG-6000模拟干旱,研究发现,轻度胁迫并未明显影响种子的萌发,而且还有一定的促进作用。随着胁迫强度增加,种子萌发呈明显降低的趋势。MDA、游离Pro、保护酶活性、可溶性蛋白质和可溶性糖含量的变化则呈单峰曲线趋势。2.干旱胁迫下,芸豆株高、叶面积、比叶重、叶片保水能力均降低,茎粗变细。随着胁迫强度增加、时间延长,变化幅度增大,但叶片保水能力变化不大。不同生育时期胁迫对株高的影响顺序为苗期>花期>结荚期。叶面积随着发育进程的推进,受影响程度加重。苗期干旱胁迫使叶绿素a含量升高,随着发育进程推进呈下降趋势,胁迫强度越大、降幅越大。叶绿素总量和叶绿素b的变化规律与叶绿素a基本相同。叶绿素a与b比值无明显的规律。复水后,冠层形态指标的反应比较滞后,而后由于补偿作用得到一定程度的恢复。株高的反应,在苗期干旱胁迫5d、花期和结荚期轻度胁迫,补偿作用最明显,而重度胁迫补偿作用相对较差弱。茎粗对胁迫及复水反应均不明显。叶面积,在花期产生激发作用,最终结荚期补偿效应最强,花期和苗期次之。比叶重,在苗期和花期轻度胁迫5d出现等量补偿,花期其他处理出现部分补偿,结荚期则表现为伤害补偿或无补偿。叶片保水能力,在苗期出现等量补偿,而花期和结荚期补偿效应不明显。叶绿素a含量,在苗期胁迫5d、花期胁迫10d及结荚期胁迫均能等量补偿。叶绿素b含量,在苗期和结荚期胁迫5d,表现为等量补偿。叶绿素a与b比值,在苗期和结荚期轻度胁迫10d和花期胁迫5d,均能等量补偿。叶绿素总量的变化规律与叶绿素a基本相同。3.干旱胁迫使芸豆主根增长,根粗变细,侧根总长增加,根系活力减小,随胁迫强度越大,变幅越大。胁迫时间延长,苗期、花期和结荚期的不同指标变化各异。胁迫使根系总吸收面积减小,强度越大、时间越长,降幅越大。苗期,根系活跃吸收面积在轻度干旱胁迫时上升,随胁迫时间延长增量减小；苗期重度胁迫、花期和结荚期胁迫使活跃吸收面积降低,随着胁迫强度增加、时间延长,降幅急剧增加。活跃吸收面积率变化规律与活跃吸收面积相一致。复水后,主根长、主根粗及侧根总长均表现出滞后效应,其他指标表现不明显。主根长在苗期和花期胁迫5d产生等量补偿,侧根总长在花期和结荚期表现为等量补偿。主根粗在苗期补偿效应最强,表现出等量补偿。根系活力均能等量补偿。总吸收面积在苗期和花期胁迫5d表现为等量补偿。根系活跃吸收面积在苗期轻度胁迫5d及胁迫10d表现为等量补偿,根系活跃吸收面积率变化规律与活跃吸收面积相同。4.干旱胁迫下,芸豆叶片SOD活性均下降,胁迫强度增加,时间延长,降幅加大。MDA含量、POD和CAT活性在干旱胁迫下上升,胁迫强度越高、时间越长,上升趋势越明显,各指标在结荚期受干旱胁迫影响程度最大。复水后,POD和CAT活性表现为激发作用。最终SOD在苗期和结荚期出现等量补偿,花期胁迫出现伤害补偿。CAT活性、MDA含量在复水后,基本能等量补偿。CAT活性补偿作用的变化没有规律,苗期胁迫5d和结荚期胁迫产生等量补偿,苗期胁迫10d产生部分补偿,而花期胁迫5d和10d分别产生了伤害补偿和超补偿效应。5.干旱胁迫,可溶性蛋白含量除结荚期胁迫10d增加外,其他处理均减少,随胁迫强度增加而降幅增大。随胁迫时间延长,苗期和结荚期降幅增大,花期降幅减小,影响程度顺序为苗期>结荚期>花期。可溶性糖和游离Pro含量在干旱胁迫下提高,随胁迫强度增加,增幅加大。随胁迫时间延长,脯氨酸含量在苗期重度胁迫下降低,其他处理均提高,随发育进程推进,增幅加大。可溶性糖含量在苗期和花期增幅减小；结荚期轻度胁迫时含量提高,重度胁迫变化不大。复水后,可溶性蛋白含量表现出激发反应,可溶性糖在花期和结荚期也均出现激发反应,最终两者均为等量补偿,且可溶性蛋白在苗期胁迫10d出现超补偿现象。脯氨酸含量在复水后出现滞后效应,最终苗期胁迫10d为等量补偿,其他处理为部分补偿甚至伤害补偿。6.干旱胁迫使芸豆冠层干重减小,根部干重增加,根冠比提高。冠层干重和根冠比在胁迫强度增加时降幅加大。随胁迫时间延长,苗期和结荚期降幅加大,花期降幅减小。根部干重随胁迫强度增加,时间延长,增幅加大。复水后,冠层干重、根部干重和根冠比均先后产生滞后效应,最终在苗期和花期均能等量补偿,而结荚期,尤其是结荚期胁迫10d补偿效果较差。7.干旱胁迫对单荚粒数影响不明显,单株荚数、粒重和单株产量呈减小趋势。随胁迫强度增加、时间延长而降幅增加。单株荚数在结荚期明显降低,粒重和单株产量在花期和结荚期均明显降低,其他生育时期变化不明显。随胁迫强度增加,时间延长,百粒重降幅加大。干物质增长的动态曲线呈“S”型,与Logistic增长模型相吻合。复水后产生一定的补偿作用,苗期等量补偿,花期和结荚期仅为部分补偿。8.干旱胁迫后用烯效唑拌种,在一定浓度范围内,除株高和MDA含量降低外,其他冠层及根系形态和生理指标、保护酶活性、渗透调节物质、冠层及根干重、根冠比等均上升。最终在产量及构成因素中,百粒重和单株产量均增加,单株荚数、单荚粒数变化不显著。但烯效唑拌种浓度较高时,除株高外,均产生与中低浓度相反的变化趋势。更多还原

【Abstract】 Drought is one of the main environmental factors that affects crop growth and development, and is also one of the most important limiting factors for crops. To understand the effects of water deficit on the growth and yield of speckled kidney bean is significant for both the studies of drought stress and the problem solving theoretically and practically.This project was carried out in agronomic experimental base of Heilongjiang Bayi Agricultural University in2012and2013using speckled kidney bean as the subject. PEG-6000(polyethylene glycol6000) of different concentrations was applied to seeds of speckled kidney bean to simulate drought stress. The seed germination and physiological characteristics were measured in this study. Pot experiments were carried out by artificial water control to study the changes of morphological, physiological characteristics and yield of speckled kidney bean under drought stress and rewater in the aspects of stages, severity and duration. According to the study, the dynamic models of dry matter accumulation of speckled kidney bean were established. Regulation of drought was investigated by uniconazole waterless-dressed seed.The main results were shown as follows:1. In the experiment of PEG-6000modifying drought stress, seed germination was not significant suppressed, but enhanced a little under mild drought stress. With the increase of drought stress, the seed germination was inhibited, protective enzyme activities and the content of protein were first increased and then decreased, while the contents of MDA, Pro and soluble sugar were increased in a unimodal curve trend.2. Drought stress in each stage altered the canopy characteristics of speckled kidney bean, and resulted in decreases in the plant height, leaf area, specific leaf weigh, water retention capacity of leaf and main stem diameter. More obvious variations were observed under stricter drought stress and longer stress duration, but there is no significant difference in leaf relative water component. The plant height in the growth period was varied in an ascending order of pod-setting stage, flowering stage and seedling stage. The leaf area was more severely affected by drought stress during growth.The content of chlorophyll a increased under drought stress in seedling stage, and then was observed a decline tendency with the development of the plant. The more serious the drought stress, the greater the decline. The trends of the level of chlorophyll b and total chlorophyll were almost the same as that of chlorophyll a, and the ratio of chlorophyll a to b was random. Canopy morphological and physiological biochemical parameters showed hysteresis effect after rewater, and then were restored to a certain degree by the compensation effect.The plant height had obvious compensation effect in seedling stage under a5-day drought stress and mild drought stress in flowering and pod-setting stage. But compensation effect was relatively poor under severe drought stress. The response of main stem diameter to the changes of drought stress and rewater was not obvious.Leaf area showed priming effect in flowering stage, eventually, the compensation effect of pod-setting stage is the best, followed by that of flowering stage and seedling stage.Specific leaf weight had equivalent compensation effect in seedling and flowering stage under5-day mild drought stress, partial compensation effect in flowering stage under other drought stress, and damage or no compensation effect in pod-setting stage.Water retention capacity of leaf showed equivalent compensation effect in seedling stage, but had no obviously compensation effect in flowering and pod-setting stage. The content of chlorophyll a had equivalent compensation effect in seedling stage under5-day drought stress,10-day flowering stage and5-day pod-setting stage. The content of chlorophyll b showed equivalent compensation effect after a5-day stress in seedling and pod-setting stage. The ratio of chlorophyll a to b had equivalent compensation effect in seedling and pod-setting stage under10-day mild drought stress and5-day flowering stage stress. The content of total chlorophyll had the same trend as that of chlorophyll a.3. Drought stress leaded to an increase of length of main and lateral roots, but resulted in a decrease of the diameter of main root and the vitality of root, the more serious the drought stress, the more obvious the variation. Along with the prolonged period of drought stress, the parameters were not changed in the same way between stages. The total root absorption area was appeared in declining trend. Higher drought stress and longer stress duration will lead to a greater declination.The root active absorption area was increased in seedling stage under mild drought stress. The increment reduced under longer stress duration.The root active absorption area was decreased in seedling stage under severe drought stress. The serious drought stress and the long stress duration resulted in great the declination of absorption area in flowering and pod-setting stages.The ratio of active absorption area had the same tendency as that of the root active absorption area. All of the lengths of main roots, lateral roots and the diameter of main roots showed hysteresis effect after rewater, other parameters were not obvious.Length of main roots was produced equivalent compensation effect in seedling stage, and in5-day flowering stage. The total length of lateral roots was observed equivalent compensation effect in flowering and pod-setting stage. The diameter of main root was observed equivalent compensation effect in seedling stage. The vitality of root had equivalent compensation effect in each stage. The total root absorption area had equivalent compensation effect in seedling stage and in5-day flowering stage, the root active absorption area had equivalent compensation effect in seedling stage under5-day mild drought stress and10-day drought stress. The trend of the ratio of active absorption area was the same as that of the root active absorption area.4. Drought stress resulted in a decline of SOD activity, the more serious the drought stress and the longer the stress duration, the greater the decline. Drought stress leaded to increases of POD activity, CAT activity and content of MDA, the more serious the drought stress and the longer the stress duration, the greater the increase. All of the parameters were affected the most by drought stress in pod-setting stage. POD and CAT activities had priming effect; SOD activity had equivalent compensation effect in seedling and pod-setting stage, and damage compensation effect occurred in flowering stage.POD activity and the content of MDA were produced equivalent compensation effect by and large. Compensation effect was changed irregularly in CAT activity. Rewater produced equivalent compensation effect in seedling stage under5-day drought stress and pod-setting stage, and partial compensation effect in seedling stage for10-day, while produced respectively damage and over compensation effect in5-day and10-day flowering stage.5. Drought stress caused the accumulation of soluble protein decreased in each stage except in10-day pod-setting stage, the more serious the drought stress, the greater the decline; the longer the stress duration, the greater the decline in seedling and pod-setting stage and the smaller the decline in flowering stage. The impact in seedling stage is larger than that in pod-setting stage which is larger than that in flowering stage. Drought stress increased the content of Pro and soluble sugar, the more serious the drought stress, the greater the increase. The longer the stress duration, the greater the decline of the content of Pro in seedling stage under severe drought stress, the later the developmental process, the greater the increase. Drought stress decreased the increment amplitude of the content of soluble sugar in seedling and flowering stage, and increased the content of soluble sugar in pod-setting stage under mild drought stress. There were no obvious variations in severe drought stress.The content of soluble protein had priming effect in each stage after rewater, so did the content of soluble sugar in flowering and pod-setting stage. All of them had equivalent compensation effect, and the content of soluble protein had over compensation effect in seedling for10-day. Rewater raised hysteresis effect to the content of Pro, in the end rewater produced equivalent compensation effect in seedling stage for10-day, and partial or damage compensation effect in other treatments.6. Drought stress decreased canopy dry weight, increased root dry weight as well as ratio of root to canopy. The more serious the drought stress, the greater the decline of canopy dry weight and ratio of root to canopy. Long stress duration leaded to the big declination in seedling and pod-setting stages, and small declination in flowering stage.The root dry weight increased intensely in response to serious drought stress and long stress duration. Rewater leaded hysteresis effect to canopy and root dry weight, and ratio of root to canopy. Final equivalent compensation effect occurred in seedling and flowering stage, while poor compensation effect occurred in pod-setting stage and in the10-day stress treatment especially.7. during harvest period, drought stress decreased pod number and yield of per plant as well as the100-grain weight, the more serious the drought stress and the longer the stress duration, the greater the decline, but there had no significant influence on the grain number per pod. Drought stress let pod number per plant decrease significantly in pod-setting stage, but the100-grain weight and the yield per plant were the same in flowering stage as in pod-setting stage.The100-grain weight was changed dynamically in s-shape curve under drought stress, the more serious the drought stress and the longer the stress duration, the greater the decline. Changes of dry substance accumulation can be described by logistic model which could give objective demonstration, the fitted effect was better. Rewater produced equivalent compensation effects in seedling stage, but partial compensation effect in flowering and pod-setting stage, and didn’t change significantly in other stages.8. After drought stress, seeds were waterless-dressed with uniconazole that is within certain concentration ranges. All of the canopy morphological and physiological parameters, protective enzyme activities, osmoregulation substance, canopy and root dry weight, ratio of root to canopy increased with increasing uniconazole concentration, except the plant height and the content of MDA which decreased significantly. The final yield and composition factors, pod number per plant and grain number per pod didn’t change significantly, while the100-grain weight and the yield per plant were increased. However, when the seeds were treated with high concentrations uniconazole, all the parameters except plant height had the opposite tendency comparing to those under lower uniconazole concentration.更多还原