氮素形态对牛鞭草光合碳同化酶及叶绿素合成的影响

Effects of nitrogen forms on photosynthetic carbon assimilation enzymes and chlorophyll synthesis in Hemarthria altissima

选用根茎型禾草牛鞭草为材料,研究硝态氮、铵态氮对牛鞭草光合碳同化酶、叶绿素合成前体及叶绿素合成的影响,探究不同形态氮与牛鞭草光合碳同化及叶绿素合成之间的关系.研究发现在m(NO-3-N)∶m(NH4^+-N)为1∶0和1∶1的氮添加条件下,磷酸稀醇式丙酮酸羧化酶(PEPC)、叶绿素合成前体5-氨基乙酰丙酸(5-aminolevulinate ALA)、胆色素原(Porphobilinogen PBG)、尿卟啉原Ⅲ(UroporphyrinogenⅢ)及叶绿素a、叶绿素b、叶绿素a+b均显著高于m(NO3^--N)∶m(NH4^+-N)=0∶1与不施氮N0,但是核酮糖-1,5-二磷酸羧化酶/加氧酶(RuBisCo)差异不显著.结果表明:在牛鞭草培养过程中,适量增加硝态氮有利于提高牛鞭草光合碳同化能力及叶绿素合成能力,从而有利于提高光合作用能力,促进其生长及发育.

In this paper,the rhizomatous grass,Hemarthria altissima,was selected as the experimental material to study the effects of ammonium nitrogen,nitrate nitrogen on photosynthetic carbon assimilation enzymes,chlorophyll synthesis precursor and chlorophyll synthesis of Hemarthria altissima,and explore the relationship between different forms of nitrogen and photosynthetic carbon assimilation and chlorophyll synthesis of Hemarthria altissima.The study found that under the condition of m(NO-3-N)∶m(NH4^+-N)1∶0 and 1∶1,phosphoenolpyruvate carboxylase(PEPC),chlorophyll synthesis precursor 5-aminolevulinic acid(ALA),porphobilinogen(PBG),uroporphyrinogenⅢ,chlorophyll a,chlorophyll b,chlorophyll a+b were significantly higher than that m(NO3^--N)∶m(NH4^+-N)0∶1 and no nitrogen application(N0),but the difference of ribulose-1,5-bisphosphate carboxylase/oxygenase(RuBisCo)was not significant.The results show that during the cultivation of Hemarthria altissima,increasing appropriate amount of nitrate nitrogen was beneficial to the photosynthetic carbon assimilation ability and chlorophyll synthesis ability,thus to the improvement of photosynthesis ability and the promotion of its growth and development.