研究环境温度升高对粳稻光合生长的影响,对于评估未来气候变暖对北方水稻生产的影响具有重要意义。采用开放式主动增温系统(Free Air Temperature Increasing,FATI),以沈农9816和港辐粳16为试验材料,设置额定功率2000 W的增温处理,以环境温度作为对照,从抽穗期开始,测定2个品种水稻剑叶的SPAD值、光合作用和叶绿素荧光参数。结果表明,增温处理使沈农9816剑叶SPAD值显著降低(P<0.05),而对港辐粳16剑叶SPAD值无显著影响;增温处理使沈农9816在抽穗后第0~30天剑叶净光合速率(P_n)显著降低(P<0.05),气孔导度(G_s)在抽穗后第0~20天也显著低于对照(P<0.05),而胞间CO_2浓度(C_i)和蒸腾速率(T_r)在抽穗后第0~40天与对照无显著差异(P>0.05)。港辐粳16仅在抽穗后第20天增温处理剑叶P_n、G_s、C_i和T_r显著小于对照(P<0.05)。增温处理使沈农9816在抽穗后第0~30天剑叶的有效光化学量子产量(Fv'/Fm')、实际光化学量子效率(Phi_(PSⅡ))、光化学淬灭系数(qP)均显著低于对照(P<0.05),非光化学淬灭系数(qN)显著升高(P<0.05)。港辐粳16在抽穗后第30~40天增温处理剑叶的Phi_(PSⅡ)、qP均显著升高(P<0.05),qN显著降低(P<0.05)。增温使沈农9816的每穗实粒数、结实率、千粒重和产量均显著低于对照(P<0.05),而对港辐粳16的产量及构成因素无显著影响。综上所述,大气温度升高条件下,不同耐热性的粳稻品种剑叶的光合和叶绿素荧光参数的变化规律存在差异,沈农9816是热敏感品种,港辐粳16具有一定的耐热性。
英文摘要:
The study on effects of environmental temperature rise on photosynthesis of rice is important to evaluate the influence of future warming on rice production in northern China. The free air temperature increasing (FATI) system for paddy fields was used to set a temperature-raising treatment with a rated power of 2000 W, and the ambient temperature was used as a control. With Shennong9816 and Gangfujing16 as materials, the SPAD value, photosynthesis and chlorophyll fluorescence parameters of rice flag leaves were measured from the heating date. The results showed that warming significantly reduced the SPAD value of flag leaf of Shennong9816 (P<0.05), while it had no significant effect on the SPAD value of flag leaf of Gangfujing16. Warming treatment reduced the net photosynthetic rate (P_n) in flag leaves of Shennong9816 from 0 to 30 days after heating (P<0.05). Stomatal conductance (G_s) was significantly lower than that of the control at the 0~20 days after heating, while intercellular CO_2 concentration (C_i) and the transpiration rate (T_r) had not significantly different from the control at the 0~40 days after heating (P>0.05). Under warming treatment, P_n, G_s, C_i, and T_r of flag leaf in Gangfujing16 were significantly smaller than those of control (P<0.05) on the 20th day after heating. Shennong9816 at 0~30 days after heating, the effective photochemical quantum yield temperature of flag leaf (Fv'/Fm'), actual photochemical efficiency (PhiPSII), photochemical quenching coefficient (qP) were significantly lower in Shennong 9816 than those in the control at 0~30 days after heating (P<0.05), and non-photochemical quenching coefficient (qN) increased significantly (P<0.05). PhiPSII and qP in flag leaf of the Gangfujing16 were significantly increased from 30 to 40 days after heating (P<0.05), and qN was significantly decreased (P<0.05). Warming significantly reduced panicle number, seed setting rate, 1000-grain mass and yield (P<0.05) in Shennong9816, but had no significant effect on the yield and composition of Gangfujing16. In summary, the photosynthetic and chlorophyll fluorescence parameters in flag leaves of different heat-resistant japonica rice varieties are different under elevated atmospheric temperature. Shennong9816 is a heat-sensitive variety, and Gangfujing16 has a certain degree of heat resistance.