大气臭氧浓度升高对大豆籽粒C、N、P和K浓度的影响

Effects of elevated atmospheric O3 on C,N,P and K concentrations in soybean seeds

为明确大气臭氧浓度升高对大豆籽粒C、N、P和K元素浓度的影响,本研究以环境大气臭氧浓度为对照,利用开顶式气室模拟大气臭氧浓度升高40 nL·L^-1的环境条件,选取3个推广面积较大的大豆品种:东生1号、绥农4号和绥农8号,解析了在高臭氧浓度下不同大豆品种籽粒C、N、P和K元素浓度及计量化学比的变化。结果表明,臭氧浓度升高会降低大豆籽粒中C元素和P元素浓度,但增加了N元素和K元素浓度,3个品种大豆籽粒中C、P元素平均浓度分别降低了1.51%和10.7%;N、K元素平均浓度则分别升高了37.8%和11.0%。虽然大豆籽粒C、N、P和K元素浓度存在品种间差异(P<0.05),但臭氧与品种交互作用对4种元素的积累影响不显著(P>0.05)。臭氧浓度升高还会改变大豆籽粒中C、N、P和K元素化学计量比,如提高C/N和C/K,降低C/P和N/P,同时提高P/K,这表明臭氧浓度升高降低了N和K的元素利用效率,而且大豆对N元素的积累和利用可能受到P元素的制约。

To understand the effects of elevated atmospheric O 3(eO 3)by 40 nL·L^-1 on carbon(C),nitrogen(N),phosphorus(P)and potassium(K)concentrations in soybean seeds,we analyzed corresponding stoichiometric ratios in open top chamber(OTC)simulation systems using 3 soybean cultivars Dongsheng 1,Suinong 4 and Suinong 8.Results showed that across the 3 soybean cultivars,eO 3 decreased soybean seed C and P concentrations on average by 1.51%and 10.7%,respectively,but increased seed N and K concentrations on average by 37.8%and 11.0%,respectively.Although significant variations of C,N,P and K concentrations in soybean seeds existed among different soybean cultivars,the interaction of O 3×cultivar on seed C,N,P and K concentrations was not significant.eO 3 increased soybean seed C/N and C/K,decreased C/P and N/P but increased P/K simultaneously.This indicate that the use efficiency of N and K in soybean reduced by eO 3,while the utilization of N under eO 3 may be limited by P but not K.