淹水胁迫下美洲黑杨无性系生理生化指标的变化

The Variation of Inner Physiological and Biochemical Characters Under Flooding Stress of Populus deltoides Clones

【研究目的】季节性淹水胁迫是滩地杨树造林的主要限制因子,建立可靠的指标体系对美洲黑杨无性系耐涝性进行评价意义重大;【方法】以美洲黑杨XL-75、XL-77、XL-90、I-69及苏柳J172为对象,分析了其内部生理生化指标对淹水胁迫的响应、性状间相关性及其遗传变异;【结果】淹水胁迫下各无性系叶绿素含量、可溶性蛋白质含量、CAT活性在总体上表现为下降的趋势;I-69杨在淹水胁迫下MDA含量较对照明显上升,XL-75、XL-77、XL-90、J-172在淹水初期MDA含量较对照略有下降,在后期出现回升的趋势;淹水15d时,5个参试材料SOD活性与对照比较均明显下降,随着淹水胁迫程度加深,SOD活性表现为依次上升趋势,而POD变化则与SOD恰好相反,二者存在明显的补偿机制;淹水30d以内时,5个参试材料ADH活性均较对照显著提高,淹水45d时,I-69杨ADH活性较对照下降56.9%,而XL-75、XL-77、XL-90、J172分别较对照提高970.4%、279.1%、555.2%和461.5%;【结论】不同处理下Chl、SOD、CAT相对值与总生物量相对值呈极显著正相关,且其广义遗传力在0.5967～0.7743之间,表明其受遗传控制程度较高,可做为不同无性系耐涝性评价的可靠指标。

[OBJECTIVE]The seasonal flooding stress was the main restriction factor for afforestation of Populus deltoides in beach land,the evaluation of flooding-tolerance ability through reliable properties was very important.[METHOD]The response of inner physiological characters,correlation among different characters and their genetic variation under flooding stress were studied objecting to Populus deltoides clones XL-75,XL-77,XL-90 and ck（ I-69,Salix×jiangsuensis ‘J172’）.[RESULT]Contents of chlorophyll,Soluble Protein and CAT activity of all clones under waterlogging stress were decreased totally compared to contrast.Content of MDA in I-69 was increased significantly compared with the contrast,Content of MDA in XL-75,XL-77,XL-90,J-172 in earlier time of waterlogging were decreased slightly compared with contrast and increased with sustain inundation.The SOD activity decreased obviously than CK in earlier time of waterlogging stress,but the POD activity rised obviously.With the waterlogging stress deepened,the SOD activity was rising one by one and the POD activity was declining one by one,both had obviously compensation on anti-oxygenation mechanism.Flooding within 30d,the ADH activity increased more obviously than CK.When flooding on 45d,the ADH activity of I-69 decreased 56.9% compared with CK,but the ADH activity of XL-75,XL-77,XL-90,J172 respectively increased 970.4%,279.1%,555.2% and 461.5% compared with CK.[CONCLUSION]The relative value of Chl,SOD,CAT had very remarkably positive correlation with the total biomass,and the heritabilities of Chl,SOD,CAT ranged from 0.5967 to 0.7743.It indicated that the variations of 3 traits were moderately or intensively inherited,and they could be used to evaluate the flooding-tolerance of populus deltoides clones.