摘要
氮素是植物必须的营养元素,对植物生长影响重大。由于硝态氮(NO_3^--N)和铵态氮(NH_4^+-N)的形态差异,两者对植物养分吸收和生理代谢的影响不同。针对雷竹Phyllostachys violascens培育中存在氮肥施用不当的问题,通过设置NO_3^--N和NH_4^+-N不同比例,即硝铵比为1∶0,2∶1,1∶1,1∶2,0∶1的5个氮素形态营养处理,测定了雷竹叶片和根系的丙二醛、可溶性蛋白质质量分数和抗氧化酶活性。结果表明:相同的硝铵比处理下,雷竹叶片丙二醛、可溶性蛋白质质量分数和抗氧化酶活性均高于根系,叶片较根系对氮素营养的响应更为敏感。随着NH_4^+-N增加,雷竹叶片和根系丙二醛质量分数均呈先降低后升高趋势,且在硝铵比为1∶1时最低;抗氧化酶活性总体上呈先升高后降低趋势,混合营养处理的抗氧化酶活性均较高,其中叶片超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性在硝铵比为1∶2时最高,过氧化物酶(POD)在纯铵处理时最高;根系SOD活性在硝铵比为1∶1时最高,CAT和POD活性在硝铵比为1∶2时最高;可溶性蛋白质质量分数也呈先升高后降低趋势,叶片和根系分别在硝铵比为1∶2和1∶1时最高。综合分析认为:混合氮素形态营养供应的雷竹叶片和根系的丙二醛质量分数较单一氮素形态供应低,且可溶性蛋白质质量分数和抗氧化酶活性均能维持在较高水平,说明混合氮素形态营养处理下雷竹受到的膜脂过氧化程度较低,抗逆性较强。
Nitrogen （N）, a necessary plant nutrient for plant growth can be applied as nitrate nitrogen （NO3^- - N ） or ammonium nitrogen （NH4^＋-N） but may have different effects on nutrient absorption and physiological metabolism of the plant. To determine a proper N fertilizer for Phyllostachys violascens cultivation, an experi-ment supplying N fertilizer with five different ratios of NO3^- -N and NH4^＋ -N （1 ： 0, 2 ： 1, 1 ： 1, 1 ： 2, and 0 ： 1） was conducted. Contents of malondialdehvde （MDA）, soluble protein, and antioxidant enzyme activities were determined. Results showed that for the same treatment ratios of NO3^- -N and NH4^＋- N, MDA content, soluble protein, and antioxidant enzyme activities were higher in leaves than in roots. As the concentration of NH4^＋ -N increased, the MDA content in leaves and roots first decreased and then increased with the lowest MDA having a ratio of 1 ： 1. Antioxidant enzyme activities first increased and then generally decreased having higher levels with mixotrophism. Superoxide dismutase （SOD） and catalase （CAT） activities in leaves were highest with the 1 ： 2 ratio; whereas SOD activity in roots was highest with the 1 ： 1 ratio, and CAT and peroxidase （POD） ac-tivities were highest with the 1 ： 2 ratio. Soluble protein content also increased first and then decreased with the highest for leaves in a 1 ! 2 ratio and for roots in a 1 ! 1 ratio. With mixed nutrition, MDA content was lower, but soluble protein content and antioxidant enzyme activities remained at much higher levels. Thus, with a mixture of NO3^--N and CH4^＋-N at a 1 ： 1 ratio, the degree of oxidative damage to leaves and roots of Phyl- lostachys violascens was least, and antioxidant enzyme activities were stronger, thereby boosting growth and biomass accumulation. [Ch, 2 fig. 1 tab. 20 ref.]
出处
《浙江农林大学学报》
CAS
CSCD
北大核心
2017年第1期14-19,共6页
Journal of Zhejiang A&F University
基金
浙江省-中国林业科学研究院省院合作项目(2013SY12)
中央级公益性科研院所基本科研业务费专项资金项目(RISF61258)
关键词
植物生理学
雷竹
铵态氮
硝态氮
硝铵比
抗氧化系统
plant physiology
Phyllostachys violascens
nitrate nitrogen
ammonium nitrogen
nitrate/ammonium ratio
antioxidant system
