文献类型：期刊文献

中文题名：缺氮胁迫下不同黑木相思基因型综合评价

英文题名：Comprehensive evaluation in different genotypes of Acacia melanoxylon under nitrogen deficiency stress

作者：陈天笑[1,2] 白小刚[1] 何茜[2] 胡冰[1] 曾炳山[1] 陆钊华[1]

第一作者：陈天笑

机构：[1]中国林业科学研究院热带林业研究所,广东广州510520;[2]华南农业大学林学与风景园林学院,广东广州510642

年份：2023

卷号：43

期号：10

起止页码：47-59

中文期刊名：中南林业科技大学学报

外文期刊名：Journal of Central South University of Forestry & Technology

收录：CSTPCD;;北大核心:【北大核心2020】；CSCD:【CSCD2023_2024】；

基金：国家重点研发计划子课题(2022YFD2200205-1);广东省林业科技创新项目(2020KJCX014)。

语种：中文

中文关键词：黑木相思;基因型;生长;生理生化;隶属函数;综合评价

外文关键词：Acacia melanoxylon;genotype;growth;physiology and biochemistry;membership function;comprehensive evaluation

分类号：S718.3

摘要：【目的】探究不同黑木相思基因型对缺氮胁迫的生长、生理生化响应,为黑木相思优良抗逆早期选育提供理论依据【方法】本研究以4个黑木相思基因型(F1、SR3、SR14和SR17)幼苗为对象,以改良霍格兰营养液为基础,利用砂培盆栽试验方法,设置CK (16 mmol·L^(-1)N素)和-N (0 mmol·L^(-1)N素)两个氮水平,探究氮缺乏对4个黑木相思基因型幼苗的生长和生理生化特性的影响,并用主成分分析结合隶属函数进行耐低氮能力综合评价。【结果】缺氮条件下,4个黑木相思基因型幼苗的苗高、地径、地上部干质量和全株干质量均被抑制,地上部分干质量和全株干质量降幅最小的基因型是F1,最大的是SR17;根干质量除F1提升外其余基因型均呈下降趋势;全株的氮素积累量均显著降低,其中F1基因型的降幅最小,降低了39%,SR17降幅最大,降低了58.2%。缺氮下4个基因型的根冠比均显著升高,根系中氮素积累量占全株比均较CK升高;而叶绿素a(Chla)含量、叶绿素b(Chlb)含量、类胡萝卜素(Car)含量和叶绿素a+b(Chla+b)含量均显著降低;4个基因型的净光合速率(Pn)均显著降低,气孔导度(Gs)均呈下降趋势,胞间CO_(2)浓度(Ci)均显著上升,气孔限制值(LS)下降,这主要是非气孔因素,其中SR17的Pn降幅最大,降低了76.8%;缺氮下SR17的F_(v)/F_(m)显著降低,并且低于0.8,而其他基因型无影响,F_(v)′/F_(m)′在F1、SR3和SR17均显著降低,而SR14无显著差异。缺氮下4个基因型的POD、CAT和SOD活性均显著提高,MDA含量也显著升高;通过对20个生长、生理生化指标进行主成分分析并结合隶属函数进行综合评价得到综合评价值,4个基因型对缺氮胁迫的适应能力排序为F1>SR3>SR14>SR17。【结论】缺氮胁迫下,4个黑木相思基因型幼苗的生长发育受到抑制,全株氮素积累量显著降低,光合色素含量降低、光合作用受到抑制;缺氮会提高抗氧化相关酶,但过量的活性氧仍给膜脂带来损害;F1耐低氮能力最强,胁迫对其影响较小,而SR17耐低氮能力最弱,表现在光合速率和全株氮素积累量降幅最大,幼苗PSII中心受损程度较大。
【Objective】To explore the growth,physiological and biochemical responses of different Acacia melanoxylon genotypes to nitrogen deficiency stress,and to provide a theoretical basis for early breeding of A.melanoxylon with excellent stress resistance.【Method】4 genotypes(F1,SR3,SR14 and SR17)seedlings of A.melanoxylon were used as objects,based on the improved Hoagland-1-1 nutrient solution,using the sand culture pot test method,two nitrogen levels including CK(16 mmol·L N)and-N(0 mmol·L N)were set to explore the effects of nitrogen deficiency on the growth and physiological and biochemical characteristics,and use principal component analysis combined with membership function to comprehensively evaluate the low nitrogen tolerance ability.【Result】Under nitrogen deficiency,the plant height,ground diameter,above-ground dry mass and the whole plant dry mass of four A.melanoxylon genotype seedlings were all inhibited,and the genotype with the smallest decrease in above-ground dry mass and whole plant dry mass was F1,the biggest one was SR17;the root dry mass of other genotypes showed a downward trend except for the increase of F1;the nitrogen accumulation of the whole plant was significantly reduced,among which the F1 genotype had the smallest decrease of 39%,and the SR17 had the largest decrease which reduction was 58.2%.Under nitrogen deficiency,the root-to-shoot ratios of the four genotypes were significantly increased,and the nitrogen accumulation in the root system was higher than that of CK;while the chlorophyll a(Chla)content,chlorophyll b(Chlb)content,(Car)content and chlorophyll a+b(Chla+b)content were significantly decreased;the net photosynthetic rate(Pn)of the four genotypes was significantly decreased,the stomatal conductance(Gs)showed a downward trend,and the intercellular CO_(2) concentration(Ci)increased significantly,and the stomatal limit value(LS)decreased,which was mainly due to non-stomatal factors.Among them,the Pn of SR17 decreased the most,reducing by 76.8%;the F_(v)/F_(m) of SR17 decreased significantly under nitrogen deficiency,and was lower than 0.8,while other genotype had no effect,and F_(v)′/F_(m)′was significantly reduced in F1,SR3 and SR17,while SR14 had no significant difference.Under nitrogen deficiency,the activities of POD,CAT and SOD of the four genotypes were significantly increased,and the content of MDA was also significantly increased;the comprehensive evaluation value was obtained by conducting principal component analysis on 20 indicators of growth,physiological and biochemical combined with membership function for comprehensive evaluation value showed that the order of adaptability of the four genotypes to nitrogen deficiency stress was F1>SR3>SR14>SR17.【Conclusion】Under nitrogen deficiency stress,the growth and development of the four genotype seedlings of A.melanoxylon were inhibited,the nitrogen accumulation in the whole plant was significantly reduced,the content of photosynthetic pigments was reduced,and photosynthesis was inhibited;nitrogen deficiency would increase antioxidant-related enzymes,However,excessive reactive oxygen species still caused damage to membrane lipids;F1 had the strongest ability to tolerate low nitrogen,and the stress had little effect on it,while SR17 had the weakest ability to tolerate low nitrogen,showing the largest decrease in photosynthetic rate and nitrogen accumulation in the whole plant,the PSII center of the seedlings was more damaged.