施肥对不同时期遮阴小麦光合、产量和品质的影响

为探究通过施肥能否减缓太阳辐射减弱对小麦生长发育及产量形成的不利影响，通过田间模拟试验，研究了不同生育期遮阴下施肥对冬小麦植株光合生理、产量和品质的影响。采用3因素3水平正交试验设计，遮阴设3水平，即不遮阴(S0，遮阴率0)、开花-成熟期遮阴(S1，平均遮阴率68%)、分蘖-成熟期遮阴(S2，平均遮阴率68%)；复合肥(N-P₂O₅-K₂O)施用量设3水平，即100 kg·hm^-2(F1)、200 kg·hm^-2(F2)和300 kg·hm^-2(F3)；硅肥施用量(以SiO₂计)设3水平，即0(R0)、200 kg·hm^-2(R1)和400 kg·hm^-2(R2)。结果表明：S1提高冬小麦开花-灌浆期旗叶净光合速率(Pn),S1和S2降低开花-灌浆期气孔导度(Gs)和灌浆期蒸腾速率(Tr)，提高胞间CO₂浓度(Ci);S1和S2降低千粒质量、结实率、产量，减少籽粒直链淀...

Effects of fertilization on photosynthetic characteristics, yield and quality in winter wheat under different shading periods

Solar radiation is one of the important factors for crop production. Decreasing solar radiation is not conducive to the growth and yield formation of wheat. Currently, it is unclear whether fertilization can alleviate adverse effects of decreasing solar radiation on wheat production. A field experiment was conducted to investigate the effects of fertilization on photosynthetic characteristics, yield and quality in winter wheat under shading with different growth stages. The orthogonal design with three factors and three levels was adopted in the experiment. Shading was set at three levels, i.e., no shading(S0, shading rate 0%), shading with flowering-maturity period(S1, average shading rate 68%), and shading with tiller-maturity period(S2, average shading rate 68%). NPK compound fertilizer was set at three supply rates, i.e., 100(F1), 200(F2), and 300 kg·hm^-2(F3); The silicate fertilizer(SiO₂) as steel slag was also set at three supply rates, i.e., 0(R0), 200(R1), and 400 kg·hm^-2(R2). Results showed that:S1 increased net photosynthetic rate(Pn) in flag leaves at winter wheat flowering-filling stage. S1 and S2 decreased stomatal conductance(Gs) at grain flowering stage, and decreased transpiration rate(Tr) during the filling period, but increased intercellular CO₂ concentration(Ci). S1 and S2 decreased 1000-grain weight, seed setting rate and yield, as well as rain amylose content and total starch content, but increased grain protein content. F1 and F2 increased Pn, Gs, Tr during flowering and filling stage, respectively; F3 increased 1000-grain weight, seed setting rate, yield, amylose content, and total starch content. Silicate supply increased Pn in flag leaves during the filling period of winter wheat. R1 increased 1000-grain weight, seed setting rate, and yield, but reduced the content of amylose, total starch and protein in grains. This study suggests that shading with the flowering-maturity period increased Pn in the flag leaves of winter wheat, but inhibited the transpiration rate at the grain filling stage and affected yield formation. Supplying compound fertilizer at 300 kg·hm^-2 and silicate fertilizer(steel slag) at 200 kg SiO₂·hm^-2 could promote photosynthesis and transpiration, improve the yield and quality, and alleviate the adverse effects of shading on winter wheat production.