涂料和遮阳网覆盖对大棚环境和辣椒光合特性的影响

利用涂料和遮阳网对塑料大棚进行了覆盖处理,研究涂料和遮阳网覆盖对棚内环境和辣椒光合特性的影响,结果表明,涂料的遮阳降温效果与其稀释比例有关,稀释比例越小,遮阳降温效果越好;除阴雨天棚内地温外,遮阳网具有明显遮光降温作用;相比遮阳网,1 3涂料能够降低阴雨天和早晚时分的遮光率,改善棚内光照,延长光照时间,降温效果好;遮阳网覆盖导致辣椒的净光合速率、气孔导度和蒸腾速率显著下降,胞间CO2浓度显著上升,不利于辣椒的光合作用,而涂料覆盖有助于改善中午强光时辣椒的光合作用,使其净光合速率和气孔导度显著上升,蒸腾速率显著下降。

Effect of coating and shading-nets on environment factors and photosyn thesis characteristics of pepper in plastic greenhouses

The environment factors in plastic greenhouses and the photosynthesis characteristics of pepper were studied by shading using coating and shading-nets.The results were showed as the following: the effects of sun-shading and cooling of coating had relation to the dilution ratio.Smaller was the ratio,better was the effect.The shading-nets also had significant effects on sun-shading and cooling except the ground temperature in cloudy and rainy days.Compared with the shading-nets,the coating with 1:3 dilution ratio would be helpful to enhance the luminance and prolong time of illumination in greenhouses in the morning and the evening or in cloudy and rainy days.Of course,it also had a better effect on temperature-lowering than that of the shading-net.It would be decreased for Pn,Gs,Tr and increased for Ci distinctly when the shading-nets were used on greenhouses,which would be disadvantage for the photosynthesis of peppers.However,the paint coating could be propitious to improve the Pn,Gs and weaken the Tr of pepper,which was good for photosynthesis under stronger light at noon.