【作者】 马文涛；

【导师】 樊卫国；

【作者基本信息】 贵州大学 ， 果树学， 2007， 硕士

【摘要】 本研究以生产上常用的柑橘砧木柚[Citrus grandis(L.)Osbeck]、甜橙[Citrus sinensis(L.)Osbeck]、枳[Poncirus trifoliate(L.)Raf.]、枳橙(Citrus sinensis(L.)Osbeck×Poncirus trifoliate(L.)Raf)、土橘[Citrus chuana Hort.ex Tseng]、红橘[Citrus tangerina Hort.ex Tanaka]、皱皮柑[Citrus vessucosa Hort]、朱橘[Citrus erythrosa Hort ex Tanaka]一年生及两年生实生幼苗为试材。采用人为模拟降雨量的方式进行土壤干旱胁迫处理，研究了干旱胁迫下不同柑橘砧木的生长量及其抗旱系数，对供试柑橘砧木的抗旱力强弱进行了评价；同时研究了干旱胁迫下不同柑橘砧木的形态变化、相关生理生化指标的变化及其与抗旱性的关系；通过组织解剖学方法，研究了不同柑橘砧木叶片组织结构与抗旱力的关系；本研究采用隶属函数法，综合各种形态及生理生化指标，对参试的柑橘砧木进行了抗旱性强弱的综合鉴定；在研究中，对用于柑橘砧木抗旱性鉴定的各种形态、生理生化指标的可靠性进行了比较，确定了可作柑橘砧木抗旱性鉴定的适宜形态、生理生化指标；确定了柑橘砧木旱能力强弱评价的适宜方法。本研究对8种柑橘砧木的抗旱性鉴定进行了盆栽试验，并采用年降雨量分别为1000mm、800mm、600mm的条件对不同柑橘砧木进行长期的、不同强度的干旱胁迫处理，将年降雨量1200mm作为对照，用生长量的相关指标进行抗旱性系数的测定。通过旱害指数与不同强度的干旱胁迫处理下的抗旱系数聚类分析得出结论：在8种柑橘砧木中，朱橘、红橘抗旱力强，枳、土橘、枳橙抗旱力中等，柚、甜橙和皱皮柑抗旱力较弱。研究结果表明，不同干旱胁迫下不同柑橘砧木植株鲜重的抗旱系数与其抗旱力强弱呈极显著正相关；不同柑橘砧木植株干茎的抗旱系数与其自身抗旱力强弱没有显著的相关性；不同柑橘砧木株高的抗旱系数与其抗旱力强弱呈极显著负相关；根冠比的抗旱系数与其抗旱力强弱有正相关的趋势，但未能达到显著水平。研究结果显示，不同柑橘砧木植株鲜重的抗旱系数和株高的抗旱系数，可以作为柑橘砧木的抗旱性鉴定的可靠指标。通过对不同柑橘砧木叶片的组织解剖观察发现，叶片的气孔大小与柑橘砧木的抗旱力强弱呈显著负相关；叶片组织疏松度与柑橘砧木的抗旱力强弱呈极显著负相关；而叶片厚度和气孔密度、叶片组织紧密度与柑橘砧木的抗旱力强弱分别呈显著和极显著正相关。研究结果表明，不同干旱胁迫下柑橘砧木的叶片组织相对含水量、叶绿素含量、游离脯氨酸含量、可溶性糖含量、可溶性蛋白含量、光合速率、水分利用率、脱落酸含量、超氧化物岐化酶活性、过氧化物酶活性的变化与供试柑橘砧木的抗旱力强弱呈显著或极显著正相关；叶片和根系的质膜透性、玉米素核苷含量的变化与供试柑橘砧木的抗旱力强弱呈极显著负相关；在年降雨量为600mm强度干旱胁迫下，赤霉素含量和丙二醛含量、蒸腾速率的变化与供试柑橘砧木的抗旱力强弱分别呈显著和极显著负相关。本研究将不同柑橘砧木所有的叶片组织结构及不同干旱胁迫下柑橘砧木的生理生化指标与旱害指数进行相关性分析，并通过计算确定叶片组织结构和各种生理生化指标在隶属函数综合评价不同柑橘砧木抗旱力强弱中的贡献率，认为柑橘砧木叶片相对含水量、离体叶片失水速率、水分自然饱和亏、需水度和CTR是柑橘砧木抗旱性鉴定的适宜指标。对干旱胁迫下柑橘砧木的叶片组织相对含水量、叶绿素a、叶绿素、根系质膜透性、超氧化物岐化酶活性、水分利用率、脱落酸、可溶性糖、可溶性蛋白、游离脯氨酸的相对含量(占1200mm降雨量下的百分比)与抗旱力强弱关系的研究结果表明，除根系质膜透性的相对值与抗旱力强弱呈极显著负相关外，其余指标的相对值均与柑橘砧木的抗旱力强弱呈极显著正相关；在年降雨量为600mm的干旱胁迫强度下，各生理指标的相对值与抗旱系数均呈极显著相关性，因此在降雨量为600mm的干旱胁迫强度下上述各生理生化指标的相对值能够可靠地反映出柑橘砧木的实际抗旱力强弱。更多还原

【Abstract】 In the study ,one and two-year seedings of some common used in manufacture citrus rootstock seedlings: Citrus gandis(L.)Osbeck, Citrus sinensis (L.) Osbeck, Poncirus trifoliate (L.)Raf, Citrus sinensis (L.) Osbeck×Poncicrus trifoliate (L.)Raf, Citrus vessucosa Hort, Citrus erythrosa Hort ex Tanaka were investigated . Using the method of simulated rainfalls to do the soil drought stress disposal, we studied 1) different growth increments of citrus rootstocks seedlings and their drought coefficients under soil drought stress, and evaluated the tested rootstocks ’ strength of drought resistance; 2)morphological change ,related change in physiological and biochemical indexes and their relationships with drought resistance; 3)the relationship between leaf tissue structure and drought resistance ;4)using subordinate function method to synthesize various morphological,physiological and biochemical indexes to obtain the integrated appraisal to different strength drought resistance; 5)in the study ,we compared the diverse reliability of morphological, physiological and biochemical indexes to point out favorable indexes of appraisal and appropriate method to evaluate the strength of drought resistance.We did pot experiment on eight citrus rootstocks seedlings for drought resistance appraisal, did long-period and different intensity drought stress disposal to different rootstocks under different annual precipitations:1000mm,800mm,600mm(1200mm as a control) and measured the drought coefficients with related growth indexes. Through cluster analysis on damage of drought index and drought coefficient under different drought stress disposal, we concluded that: in the eight rootstocks,C.erythrosa Hort ex Tanaka and C.tangerina Hort.ex Tanaka have the best drought resistance; P.trifoliate (L.) Raf.and C.chuana Hort.ex Tseng are in the medium; C.grandis(L.)Osbeck,C.sinensis (L.) Osbeck,C.vessucosa Hort and C.sinensis (L.) Osbeck×P.trifoliate (L.) Raf are weaker in the drought resistance.The study stated that under drought stress,drought coefficient with different fresh weight and the drought resistance have extremely significantly positive correlation; that drought coefficient of different plant scapus is not remarkably correlated with strength of drought resistance; that drought coefficient of different plant height and drought resistance have extremely significantly negative correlation; and that coefficient of root-shoot ratio and drought resistance are prone to the positive correlation, but not very significant. And so, drought coefficient of different plant fresh weight and coefficient of plant height can be chosen as reliable indexes to identify drought resistance in different citrus rootstocks seedlings.From observation of tissue anatomy of different citrus rootstocks seedlings leaves, we knew that leaf stomata size and strength of drought resistance have significantly negative correlation; sponge rate has extremely significantly negative correlation with drought resistance; and leaf thickness and stomata density,leaf tissue tightness respectively have positive correlation significantly and extreme significantly with drought resistance.The research also showed that under different drought stress ,leaf tissue’s changes in relative water content.chlorophyll content,free proline content,soluble sugar(Ssug) content,soluble protein(Spr) content,photosynthetic rate,water utilization efficiency,abscisic acid content,suoeroxide dismutase(SOD) activity and peroxidase(POD) activity are positively significant or extremely positively significant correlated with drought resistance ; changes of penetration of plasalemma of leaf and root system and ribosylzeation(ZR) content have extremely significantly negative correlation with drought resistance; under the drought stress of the annual precipitation 600mm ,gibberrllin(GA) content and malonidial dehyde(MDA) content,transpiration rate changes have significantly and extremely significantly negative correlation with drought resistance.In the study we did relevant analysis between all leaf tissue structure、physiological and biochemical indexes under different drought stress and damage of drought index , and figured out the contribution of them to the integrated evaluation of drought resistance through Subordinate Function to draw the conclusion that citrus rootstocks seedlings leaf relative water content(RWC),cut-leaf water loss rate(CLWR),nature water saturation deficit(NWSD),water requirement and CTR are appropriate indexes to evaluation drought resistance.Research on the relationship between drought resistance and leaf tissue relative water content,relative content (the percentage of them to that under annual precipitation 1200mm) of chlorophyll a(Chla),chlorophyll,relative penetration of plasalemma (RPP)of root system,SOD activity,water utilization efficiency(WUE),abscisic acid(ABA),Ssug,Spr,free praline showed that aside from relative penetration of plasalemma’s extremely significantly negative correlation, the others all have extremely significantly positive correlation coefficient; under the drought stress of precipitation :600mm , each index has extremely significantly correlation coefficient, and therefore the above relative values of every physiological and biochemical index under drought stress of precipitation 600mm can reliably reflect citrus rootstocks seedlings drought resistance.更多还原