摘要
模拟江苏如东滨海盐渍土的离子种类和含量,将2种中性盐(NaCl、Na2SO4)和1种碱性盐(NaHCO3)混合,配成3、5和8 g.kg-1混合盐溶液,研究其胁迫对南天竹(Nandina domestica)、海桐(Pittosporum tobira)、黄杨(Buxus sinica)、铺地柏(Sabina procumbens)和石楠(Photinia serrulata)这几种常用绿化灌木的盐害指数、相对干质量、叶绿素含量、叶片细胞膜透性、超氧化物歧化酶(SOD)活性和过氧化物酶(POD)活性等的影响。结果表明,随着混合盐浓度的升高,各灌木的盐害指数和盐害率基本上在增大,增幅由大到小依次为南天竹、石楠、黄杨、铺地柏和海桐,且南天竹在含盐量为5 g.kg-1时全部死亡。根据Logistic方程求得,南天竹、海桐、黄杨、铺地柏和石楠的耐盐阈值分别为1.74、11.46、6.03、9.63和4.75 g.kg-1。随着盐胁迫程度的增强,海桐、铺地柏、黄杨和石楠的相对干质量和叶绿素含量总体呈下降趋势;4种灌木叶片细胞膜透性则随着盐胁迫程度的增强而呈增加趋势,且海桐和铺地柏的增幅小于黄杨和石楠。此外,3个盐胁迫处理海桐和铺地柏叶片SOD活性均高于对照,而黄杨和石楠在3 g.kg-1盐胁迫下高于对照,在5和8 g.kg-1盐胁迫下则低于对照。随着混合盐浓度的升高,各灌木叶片POD和过氧化氢酶(CAT)活性基本上呈升高趋势,其中,海桐叶片CAT活性增幅最大,铺地柏叶片POD活性增幅最大,表明两者清除氧自由基的能力强。综上可见,海桐和铺地柏的耐盐性较强,可在沿海绿化中发挥重要作用。
Simulating chemical properties of the coastal alkaline soil, e.g. ion composition and concentrations of the ions, in Rudong County, Jiangsu Province, two neutral salts （ NaCl and Na2 SO4 ） and one alkaline salt （ NaHC03 ） were blended into a mixed-salt solution, which was used in this study on its stresses on growth and physiological indices of Nandina domestica , Pittosporum tobira , Buxus sinica , Sabina procumbens and Photinia serrulata , by investigating salt injury index, relative dry weight, chlorophyll content, leaf cell membrane osmosis, superoxide dismutase （SOD） and peroxidase （POD） in four treatments, i.e. control （0）, 3, 5 and 8 g·kg-1. Results show that salt injury index and salt injury rate of the 5 shrubs increased with increasing salt concentration, and the effect varied significantly between the 5 plants, showing an discending order of N. do mestica, P. serrulata, B. sinica, S. procumbens and P. tobira. Calculation using the Logistic equation shows that the salt-tolerance threshold of N. domestica, P. serrulata, B. sinica, S. procumbens and P. tobira was 1.74, 11.46, 6.03, 9. 63 and 4.75 g·kg-1, respectively. Moreover, N. domestica was extremely damaged by salt with all the seedlings dead in 5 g·kg-1 treatment. Thus, its physiological indices were not tested in present study. On the whole, with increasing stress, relative dry weights and chlorophyll contents in leaves of the 4 shrubs were found decreasing in this experiment, while leaf membrane osmosis of the plants increased, and the effect was less significant on P. serrulata and S. procumbens than on the other two. Moreover, compared to the plants in control, S. procumbens and P. tobira in the other 3 treatments were higher in superoxide dismutase activity, whereas P. serrulata and B. sinica was higher only in 3 g·kg-1treatment and lower in 5 and 8 g ·kg-1 treatments. With increasing salt concentration, all the plants showed a rising trend in peroxidase and catalase activity, and the effect on catalase activity of P. t
出处
《生态与农村环境学报》
CAS
CSSCI
CSCD
北大核心
2013年第2期197-202,共6页
Journal of Ecology and Rural Environment
基金
国家科技支撑计划(012BAB03B04)
江苏省交通厅项目
关键词
混合盐
胁迫
耐盐性
评价
耐盐生理指标
酶活性
mixture salt
stress
salt tolerance
assessment
physiological index of salt tolerance
enzyme activity
