不同花生品种对干旱胁迫与复水的响应及其机理

发布时间：2018-01-19 15:14

本文关键词： 花生抗旱性光合特性抗氧化渗透调节品质　出处：《山东农业大学》2017年博士论文　论文类型：学位论文

【摘要】：花生是种植面积仅次于油菜的我国重要的油料作物,占油料作物栽培面积的1/4,总产位居全国油料作物之首,占到50%以上。由于花生耐旱耐瘠性较强,因此成为干旱、半干旱雨养区农业生产中的首选作物。在中国及世界各地,花生通常种植在沙壤土或缺乏灌溉条件的地区,花生的种植区大多数都存在着生长季节降雨量分布不均匀,并且年度、月份间波动较大的问题。虽然相比其他作物来说,花生耐旱性较强,但是在花生生长的需水关键期,水分的缺乏同样会对花生的生长发育造成严重的甚至是不可逆的抑制。据统计,我国有70%的花生种植面积受到干旱威胁,每年由此造成的产量损失达到30%~50%。与此同时,干旱还导致品质下降,黄曲霉污染的几率大大增加。因此,干旱胁迫是限制花生产量和质量提高的最重要的非生物胁迫因子。本研究,选择了5个抗旱性不同的花生品种,分别在苗期和结荚期对其进行干旱及复水处理,研究其植株性状、光合特性、渗透调节功能、脯氨酸代谢途径、抗氧化特性、荚果和籽仁品质等性状的变化,明确了不同花生品种的抗旱机理,对于花生种质资源的抗旱性鉴定和评价,挖掘不同花生品种的优势抗旱性状,加强抗旱育种的针对性和节水栽培的有效性具有指导作用。试验于2013-2014年在山东农业大学农学试验站进行,主要研究结果如下:1.不同花生品种生物量(产量)与抗旱性表现抗旱系数是受到干旱胁迫的作物产量与未受到干旱胁迫的对照的作物产量的比值,它是目前抗旱性鉴定评价工作中应用较广的评价标准。以抗旱系数法评价5个品种的抗旱性结果发现,5个品种在苗期干旱和结荚期干旱复水处理后的抗旱性表现一致,抗旱性大小依次为荔浦大花生山花11花育20ICG6848花17。苗期和结荚期干旱处理后立即对5个品种的抗旱性进行鉴定的结果与此差异很大,说明干旱胁迫后的花生植株在干旱复水后都有补偿效应。实际生产中干旱的发生通常是间歇性的,应该对干旱复水后的补偿效应加以重视。2.生物量与收获指数对结荚期干旱胁迫及复水的响应差异荔浦大花生抗旱性最强是因为它在干旱胁迫后生物量没有显著变化,而收获指数升高。而花17由于茎重百分比升高,在干旱解除后无法再分配,造成对同化物的浪费,同时生物量显著降低,收获指数显著降低,因此它的产量显著降低,抗旱系数表现为最低。3.植株性状对干旱胁迫及复水的响应差异在所考察的植株性状中,苗期和结荚期干旱胁迫都对侧枝长的影响最显著。不同花生品种的主茎节数在不同的水分环境中相对稳定。主茎绿叶数受结荚期干旱胁迫影响较大,除山花11以外的4个花生品种,在结荚期干旱复水后主茎绿叶数与对照的比值显著升高,说明干旱胁迫延长了它们的生育时期。由于在花生生产中第一对侧枝的生长发育状况直接影响到植株整体开花结果的数量,因此侧枝长的变化也是干旱胁迫对花生产量影响的一个方面。就品种而言,苗期干旱胁迫复水后山花11和ICG6848的侧枝生长恢复较好;结荚期干旱胁迫复水后荔浦大花生的侧枝长与对照接近。而花17在苗期和结荚期干旱胁迫时,侧枝长受到的抑制在5个品种中都是最小的,但是干旱复水以后,它的补偿效应最低,生长恢复程度最小。4.光合特性对干旱胁迫及复水的响应差异苗期干旱胁迫并没有对花生的光合特性造成不可逆的抑制,5个花生品种在苗期干旱胁迫时光合特性和主要荧光参数都下降,而复水以后它们大多表现出小幅超补偿效应。SPAD值在苗期不同水分环境中表现稳定。说明苗期适度干旱反而可能对产量的增加有促进作用。结荚期光合器官及光合代谢过程对水分敏感,结荚期干旱胁迫使5个花生品种叶片SPAD值升高,复水后又下降,抗旱性较弱的ICG6848和花17的光合性能、荧光参数在干旱时下降,复水以后没有完全恢复到对照水平,这是它们抗旱性较低的生理基础。5.渗透调节对干旱胁迫及复水的响应差异脯氨酸、可溶性糖、游离氨基酸和可溶性蛋白在干旱胁迫时均在不同程度地发挥渗透调节作用,在这4种有机渗透调节物质中,脯氨酸是最主要的渗透调节物质。苗期,抗旱性强的荔浦大花生和山花11,抗旱性中等的花育20叶片中渗透调节物质对干旱胁迫的响应较敏感快速,并且在复水后都能快速恢复到对照水平,这是它们在复水后生长恢复较好,抗旱性提高的一个原因。而抗旱性弱的ICG6848和花17的渗透调节物质的含量在复水后没有及时恢复到对照水平,因此其生长发育相对缓慢,表现为较低的抗旱性。结荚期干旱复水后,抗旱性强的品种中脯氨酸含量仍然高于对照,这使花生能够较好地减缓生长中后期其他潜在的环境胁迫所带来的损伤,有利于产量的形成。而抗旱性弱的花生品种复水后叶片中可溶性糖的含量较高,说明同化物无法顺利输送到荚果,不利于荚果的发育成熟,产量降低,抗旱性降低。6.脯氨酸代谢对干旱胁迫及复水的响应差异脯氨酸的合成主要包括鸟氨酸途径和谷氨酸途径两条途径。前者的关键酶为P5CS,后者的关键酶为δ-OAT。PDH是植物体内控制脯氨酸降解的关键酶。不同生育时期的干旱胁迫诱导的脯氨酸代谢途径有所不同。苗期干旱胁迫脯氨酸含量的升高主要由于P5CS的活性增大。结荚期时,花生叶片中脯氨酸含量的变化主要是由OAT和PDH活性相应变化,协同作用的结果。7.抗氧化特性对干旱胁迫及复水的响应差异干旱胁迫使各花生品种的超氧化物清除相关酶如SOD、POD和CAT活性有不同程度提高。苗期干旱胁迫复水后,较高的POD、CAT活性与花生较高抗旱性的获得有关。而结荚期干旱复水后,较高的SOD、CAT活性对花生中后期的生长恢复有利,也有利于缓解其他潜在环境胁迫的损伤,从而有利于荚果产量的形成,是花生品种获得较高抗旱性的一个重要原因。8.品质对结荚期干旱胁迫及复水的响应差异结荚期干旱胁迫后,荔浦大花生的产量升高是通过增加荚果数、提高总的饱果重,减少秕果数、降低总秕果重实现的。其余4个花生品种在干旱胁迫后产量降低,主要是由于荚果和籽仁重量的降低导致的。只有花育20在干旱胁迫后籽仁中粗蛋白和氨基酸含量升高,其余品种均降低,荔浦大花生和花育20籽仁中三种限制性氨基酸的比例有所升高。五个花生品种在干旱胁迫后含油量均降低,除花17以外,油亚比均升高。说明花生籽仁品质的变化与品种抗旱性大小不相关。
[Abstract]:Peanut is China's rapeseed planting area is second important oil crops, oil crops cultivation area of 1/4, the total production of oil crops ranked first, accounting for more than 50%. Because of drought resistance barren strong, became arid, semi-arid rainfed crop area preferred in agricultural production in the world and China. Around, peanuts are usually planted in sandy loam or lack of irrigation area, the peanut planting area most are growing season the uneven distribution of rainfall, and the annual fluctuation, problems between months. Although compared to other crops, the peanut drought tolerant, but in the growth of peanut the critical period of water requirement, water the same lack of will on the development of peanut growth caused by severe or irreversible inhibition. According to statistics, China has 70% of the peanut planting area drought threatened, the yield loss caused by up to 30 per year %~50%. at the same time, the drought has lead to a decline in quality, the probability of aflatoxin contamination is greatly increased. Therefore, drought stress is limiting the yield and quality of peanut increased the most important abiotic stress factors. This study chose 5 different drought resistant peanut varieties respectively in seedling stage and podding stage of drought and rewatering study on the processing, plant traits, photosynthetic characteristics, osmotic adjustment, proline metabolism, antioxidant properties, changes of pod and seed quality traits, the drought resistance mechanism of different peanut varieties, for drought resistance identification and evaluation of peanut germplasm resources, the advantages of mining drought resistance traits of different peanut varieties, has a guiding role to strengthen the pertinence and effectiveness of water saving cultivation of drought resistance breeding. The test in 2013-2014 at the experimental station of Shandong Agricultural University, the main research results are as follows: 1. Different Peanut Varieties Biomass (yield) and drought resistance performance of drought resistance coefficient was affected by drought stress and crop yield under drought stress ratio control of crop production, which is currently widely used evaluation criteria to evaluate the drought resistance identification work. The results of drought resistance to drought resistance coefficient method to the evaluation of 5 varieties, 5 varieties rewatering after drought resistance under drought showed consistent drought at seedling stage and podding stage, drought resistance order of Li Riverside big peanut Huayu Shanhua 11 20ICG6848 spent 17. at seedling stage and podding stage of drought treatment immediately after the identification of drought resistance of 5 varieties of results with this difference, that after drought stress of peanut plants a compensation effect after re water. In the actual production of drought occurrence is usually intermittent, should be on the podding stage of drought stress to.2. biomass and harvest index of drought compensation effect of rewatering The strongest response difference of Li Riverside peanut drought resistance force and rewatering after drought stress because of its biomass did not change significantly, but the harvest index increased. While spending 17 due to increased percentage of stem weight, not redistribution in drought relief, caused by the assimilation of waste, while the biomass decreased significantly, harvest index decreased significantly therefore, it is the significant decrease of yield, drought resistance coefficient showed the lowest.3. plant traits of drought stress and Rewatering in response to differences in plant traits investigated in seedling stage and podding stage, drought stress has effect on branch length is the most significant. The number of nodes of the main stem of Different Peanut Varieties were relatively stable in different water environment. The number of green leaves under drought stress affected podding stage, 4 peanut varieties except flowers except 11, significantly increased in the ratio of the number of green leaves and the control pod period after re watering, drought stress To extend their growth period. Because the number of collateral in peanut production first on the growth status directly affects the whole plant fruit, a change in collateral is a long effect of drought stress on peanut yield. The varieties, drought stress after rewatering Shanhua 11 and ICG6848 branch growth recovery good; podding stage of drought stress after rewatering in Li Riverside big peanut and branch length is close to control. And spent 17 in seedling stage and podding stage of drought stress, are the smallest branch length by inhibition in 5 varieties, but after re watering, the compensation effect of the lowest growth recovery degree minimum.4. the differences in response to stress on Photosynthetic Characteristics of drought stress and rewatering under drought and no photosynthetic characteristics of peanut light caused by irreversible inhibition, photosynthetic characteristics and main stress in drought at seedling stage of 5 Peanut Cultivars The fluorescence parameters are decreased after rewatering and most of them showed a slight overcompensation effect.SPAD value was stable at the seedling stage in different water environment. That seedling moderate drought may contribute to increased production. Pod photosynthetic organs and photosynthetic metabolism process of water sensitivity, pod period of drought stress increased leaf SPAD 5 peanut varieties increased, and then decreased after rewatering, the drought resistance of weak ICG6848 and spend 17 of the photosynthetic performance, fluorescence parameters decreased during drought and rewatering after not fully recovered to the control level, this is the regulation of the differences in response to drought stress and rewatering of proline, soluble sugar and low permeability are drought resistance the physiological basis of.5., free amino acid and soluble protein in the drought stress in different degree play a role in osmotic adjustment, in which 4 kinds of organic osmolytes, proline is the most important osmotic Regulator. Seedling, drought resistant peanut and Li Riverside Shanhua 11, medium resistance of Huayu regulator in response to drought stress is sensitive to rapid penetration of 20 leaves, and quickly returned to the control level in the rehabilitation of water, it is better in their growth recovery after rewatering, a the reason of drought resistance increased. But the content of weak drought resistance ICG6848 and spend 17 of osmolytes in the complex water does not recover in time to the control level, so its growth is relatively slow, as drought resistance low. Pod period after re watering, drought resistant varieties proline content is still higher than the the control, which can be used to slow the growth of peanut in the late period of other potential environmental damage caused by stress, is conducive to the yield formation. The higher content of leaves and drought resistant peanut varieties after water soluble sugar, with no matter Successfully transported to the pod, is not conducive to the development of pod maturity, yield decreased, drought resistance decreased.6. synthesis of proline metabolism differences in response to drought stress and rewatering of proline and glutamate pathways including the ornithine pathway in two ways. The former is the key enzyme of P5CS, the key enzyme for Delta -OAT.PDH is a key enzyme in plants in the control of proline degradation. During the different growth periods of drought stress induced proline metabolic pathway is different. The proline content under drought stress increased mainly due to the increase of P5CS activity. At podding stage, changes of proline content in peanut leaf is mainly composed of OAT and PDH activity changes, the synergistic effect of the.7. on antioxidant properties of difference in response to drought stress and rewatering drought stress the peanut varieties of superoxide scavenging enzymes such as SOD, POD and CAT activity increased in different degrees. Under drought stress after rewatering, higher POD, higher CAT activity and drought resistance of peanut pod. On and after re watering, higher SOD and CAT activity of peanut in the late growth recovery benefit, but also conducive to ease other potential environmental stress, which is conducive to the formation of the pod yield. The drought resistance of peanut varieties is obtained high quality.8. an important reason for differences in response to drought at podding stage, drought stress and rewatering at podding stage after stress increased, Li Riverside peanut yield by increasing the number of pods, the total pod weight, reduce blighted pods, reduce the total grain fruit weight to achieve. The remaining 4 peanut cultivars reduced yield under drought stress, is mainly due to the decrease of pod and kernel weight of lead. Only Huayu crude protein and amino acid content of 20 seeds under drought stress increased, the varieties were reduced, Li Riverside big peanut The proportion of three limiting amino acids in the 20 seed kernel of Huayu three increased. The oil content of five peanut varieties decreased after drought stress, and the ratio of oil to seed increased.

【学位授予单位】：山东农业大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：S565.2

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