东北春大豆品种东生1号对臭氧胁迫的响应

Responses of Soybean Cultivar Dongsheng-1 to Different O_3 Concentrations in Northeast China

采用开顶式气室(OTCs)方法,研究了不同臭氧(O3)浓度处理对春大豆品种"东生1号"的影响,主要包括产量与产量构成因子,叶片与籽粒碳、氮元素与碳氮比、盛花期叶片气体交换速率、叶绿素荧光参数与光合色素含量变化.试验设置3个臭氧水平:过滤大气(CFA,10 nL·L-1)、自然大气(NFA)与自然大气添加40 nL·L-1(NFA+O3).结果表明,经过一个生长季处理(AOT40值累积为10.6μL·L-1·h),与CFA相比,NFA处理东生1号大豆单株产量与百粒重降低4.5%、4%,而NFA+O3处理分别显著降低34%、18%(P<0.05),而处理间株高、主茎节数、单株荚数与每荚粒数均无显著变化.鼓粒期NFA+O3处理叶片C、N元素含量分别显著增加3%、26%,碳氮比则显著降低18%.CFA与NFA相比,NFA+O3显著降低盛花期大豆叶片净光合速率(Asat)、气孔导度(gs)、水分利用效率(WUE)、开放的光系统反应中心激发能捕获效率(F'v/F'm)和作用光下光系统Ⅱ的实际量子效率(ΦPSⅡ),而胞间CO2浓度(ci)、光化学猝灭系数(qP)和光合色素含量则无显著变化.结果表明,O3浓度升高导致东生1号单株产量下降的主要原因是其显著降低百粒重、净光合速率和电子传递效率.

Soybean cultivar Dongsheng No. 1 [Glycine max( L.) Mer.]was exposed to charcoal-filtered air( CFA),non-filtered air( NFA) and non-filtered air with ozone addition( NFA + O3) in nine open-top chambers. Individual yield and yield components at maturity,C,N concentration in leaf and seed,gas exchange,chlorophyll a fluorescence and pigments content at the full bloom stage were measured with an AOT40 value of 10. 6 μL·L- 1·h during the growing season. Compared to CFA,NFA reduced individual yield and 100-seed weight by 4. 5% and 4% respectivley,while NFA + O3treatment significantly reduced each of them by 34% and 18%. However,plant height,node numbers of main stem,pods per plant and number of seeds per pod remained unchanged by O3addition. Leaf C,N concentrations at the seed filling stage under NFA + O3also significantly increased by 3% and 26%,respectively,while the CN ratio significantly decreased by 18%. Moreover,compared to CFA and NFA,NFA + O3caused significant reductions in the photosynthetic parameters at the full bloom stage,e. g. significant declines in net photosynthetic rates,stomatal conductance,water use efficiency,fluorescence parameters of F'v/ F'mand ΦPSⅡ. It is proposed that lower photosynthetic rates,reduced photochemical efficiency in PSⅡ and the decline in 100-seed weight might be the main reasons contributing to the lower individual yield of soybean plant by elevated O3.