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
【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 de
作者
陈天笑
白小刚
何茜
胡冰
曾炳山
陆钊华
CHEN Tianxiao;BAI Xiaogang;HE Qian;HU Bing;ZENG Bingshan;LU Zhaohua(Research Institute of Tropical Forestry,Chinese Academy of Forestry,Guangzhou 510520,Guangdong,China;College of Forestry and Landscape Architecture,South China Agricultural University,Guangzhou 510642,Guangdong,China)
出处
《中南林业科技大学学报》
CAS
CSCD
北大核心
2023年第10期47-59,共13页
Journal of Central South University of Forestry & Technology
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)。
关键词
黑木相思
基因型
生长
生理生化
隶属函数
综合评价
Acacia melanoxylon
genotype
growth
physiology and biochemistry
membership function
comprehensive evaluation
