硅氮配施对水稻光合特性、叶绿素荧光及产量的影响

为探明氮肥和硅肥用量对水稻光合作用及叶绿素荧光参数的调控效应，及氮硅配施调控水稻光合作用的内在生理基础。以超级稻品种广两优476为供试材料，采用2个氮肥水平、3个硅肥水平的大田试验，研究氮硅互作对水稻光合及荧光特性的影响。结果表明，增施氮肥和硅肥均能提高水稻叶片叶绿素含量，低氮水平下高硅肥处理光合作用最强，高氮水平下中硅肥处理光合作用最强，适当增施氮肥有利于水稻叶片降低非辐射能量耗散，将更多的吸收光能用于光化学反应，低氮水平下增施硅肥能有效改善叶绿素荧光参数指标，提高水稻叶片光合性能，但在高氮条件下，随着硅肥用量的增加，初始荧光（F0）、非光化学淬灭系数（NPQ）表现为先减后增，而PSⅡ潜在活性（Fv/F0）、实际光化学效率（ΦPSⅡ）表现为先增后减，表明硅肥过量会导致水稻光化学效率下降。硅氮互作对水稻光合生理指标影响显著，低氮水平下增施硅肥能有效改善水稻叶片光合性能，高氮水平下适宜的硅肥用量为37.5 kg/hm2，此时水稻叶片光能利用效率最高，利于光合产物的形成和积累，可为高产打下良好的基础。

Effects of the Combined Application of Silicon and Nitrogen Fertilizer on Photosynthetic,Chlorophyll fluorescence and Yield of Rice

In order to investigate regulating effects of combined application of nitrogen and silicon fertilizer on photosynthesis and chlorophyll fluorescence parameters, and intrinsic physiological basis about silicon-nitrogen fertilizer regulation of photosynthesis in rice, using super rice Guangliangyou 476 as material, two nitrogen levels and three levels of silicon fertilizer in field experiment were applied . The results showed that increasing nitrogen and silicon can improve rice leaf chlorophyll content, photosynthesis under low nitrogen high silicon levels and higher nitrogen middle silicon levels processing strongest, appropriate nitrogen fertilization in favor of reduced non-radiative energy dissipation of rice, will absorb more light energy for photochemical reaction. Increasing silicon fertilizer can effectively improve the chlorophyll fluorescence parameters of indicators and the performance photosynthesis of rice leaf under low nitrogen levels, but under high nitrogen conditions, along with the amount of silicon increased the initial fluorescence(F0), non-pho-tochemical quenching coefficient(NPQ) were increased after the first cut, and PSⅡpotential activity(Fv/F0), the actual photochem-ical efficiency (ΦPSⅡ) were increased and then decreased. This showed that silicon overdose photochemical efficiency will lead to a decline. Effects of silicon-nitrogen interaction were significantly on rice photosynthetic indexes, silicon fertilizer can effectively im-prove the performance of rice leaf photosynthesis under low nitrogen levels, and the appropriate amount of silicon is 37.5 kg/hm 2 under high nitrogen levels, then the light use efficiency is highest, and conducive to the formation and accumulation of photosynthetic prod-ucts for high-yield cultivation.