摘要
通过对枫杨、水杉、中山杉 601、苏柳 172、腺柳 5 个树种扦插苗进行 5cm(浅淹水)、10 cm(深淹水)淹水胁迫处理,研究 5 个树种对不同淹水胁迫处理的生理响应,并对其耐涝性进行综合评价,以期为长江沿岸景观防护林的筛选提供参考.结果表明:淹水胁迫下,苏柳 172 的总叶绿素(Chla+Chlb)、赤霉素(GA3)、脱落酸(ABA)含量均显著升高,其叶片变小、叶色深绿,对淹水胁迫具有较强的适应性.水杉在淹水胁迫下总叶绿素/类胡萝卜素[(Chla+Chlb)/Car]比值和玉米素核苷/吲哚乙酸(ZR/IAA)比值均较高,其超氧歧化酶(SOD)、过氧化氢酶(CAT)活性和脯氨酸(Pro)含量也均较高.在淹水胁迫下,枫杨的Chla+Chlb含量、SOD活性显著下降,过氧化氢(H2O2)含量显著升高,叶色明显变黄,但非光化学淬灭系数(NPQ)、类胡萝卜素(Car)、Pro、ABA含量提高,说明其具有较高的抗氧化能力.相比于深淹水处理,浅淹水处理下腺柳的苗高增量、光化学淬灭系数(qP)、光合色素、吲哚乙酸(IAA)、玉米素核苷(ZR)含量均较高,其可在浅淹水条件下生长,深淹水对其生长不利.淹水胁迫下,中山杉 601 的 Chla+Chlb、CAT、ABA含量均出现显著的下降趋势,而丙二醛(MDA)含量和相对电导率(REC)增量最大,说明其受到的氧化胁迫较其他树种大,但仍然能在淹水条件下生长.经综合评价,这 5 个树种在浅淹水处理下的耐淹性依次顺序为:枫杨>腺柳>苏柳172>水杉>中山杉 601;在深淹水处理下的耐淹性排序依次为:苏柳 172>水杉>枫杨>腺柳>中山杉 601.综上所述,5 个树种均对淹水胁迫具有较强的适应性,适合做为景观防护林树种.
Abstract
Five tree species seedlings such as Pterocarya stenoptera(PS),Metasequoia glyptostroboides(MG),Taxodium mucronatum×T.distichum'Zhongshanshan'601(TA),Salix chaenomeloides(SC),and Salix jiangsuensis J-172(SJ)were waterlogged at 5 cm(shallow waterlogging)and 10 cm(deep waterlogging)in the field.The effects of waterlogging on photosynthetic traits,hormones,and antioxidants on these tree seedlings were investigated and their waterlogging tolerance was evaluated.The results showed that the contents of chlorophyll,gibberellin(GA),and abscisic acid(ABA)increased in SJ seedlings under waterlogging condition,and the leaves became smaller and greener than those of the control.SJ showed strong adaptability to waterlogging stress.MG seedlings had higher levels of[(Chla+Chlb)/Car],ZR/IAA,SOD,CAT,and proline under deep waterlogging treatment than those under shallow waterlogging treatment;therefore,MG seedlings are more suitable for deep flooding condition.Waterlogging decreased the levels of chlorophyll and SOD activity,increased H2 O2,and made the leaf yellower in PS seedlings.However,PS seedlings alleviated oxidative stress by increasing the levels of Car,NPQ,proline,and ABA and grew better in shallow waterlogging than in deep waterlogging treatment.The levels of height increment,pigment,qP,and IAA or ZR in SC seedlings were all higher in shallow waterlogging than those in deep waterlogging or CK treatment.SC can grow under shallow waterlogging conditions;however,deep waterlogging is unfavorable to its growth.Under waterlogging condition,the levels of chlorophyll,CAT,and ABA in TA seedlings decreased significantly,whereas MDA and REC increased the most in the five tree species.This indicate that TA seedlings were subjected to the highest oxidation stress compared to other tree species;however,TA seedlings could still grow under waterlogging conditions.Comprehensive assessment showed that the order of waterlogging-tolerance of the five tree species under shallow waterlogging was:PS>SC>SJ>MG>TA and the order under deep waterlogging was SJ>MG>PS>SC>TA.In summary,the five tree species showed strong adaptability to waterlogging stress and are suitable for landscape protection of forest species.This study provides important reference for the screening of landscape protection of forest along the Yangtze River.
基金项目
江苏省农业科技自主创新项目(CX19100401)
江苏省林业科学研究院自主创新项目(ZZKY202102)
维普
万方数据