| In order to study the physiological mechanism of wheat yield reduction resulted from the Alopecurus japonicus Steud. stress,Yangmai 16 and Ningmai 13 were selected as materials in pool-culture experiment to study the effects of Alopecurus japonicus Steud. with eight densities (0,10,20,40,80,160,320,640 plants per square meter) on photosynthetic characteristics,chlorophyll fluorescence parameters and activities of key photosynthetic enzymes in wheat,and meanwhile,to compare the competitive ability of two wheat varieties. The results showed that,with the increasing of Alopecurus japonicus Steud. density,plant height,panicle length,net photosynthetic rate,Rubisco activity and yield of wheat were decreased in varying degrees. When Alopecurus japonicus Steud. density was greater than 20 plants per square meter,the net photosynthetic rate and yield of Yangmai 16 were decreased significantly by 11.6%-15.9%,15.5%-50.8%,and those of Ningmai 13 were decreased significantly by 6.5%-14.6%,25.1%-49.2%. Simultaneously,the declines in panicle length,leaf net photosynthetic rate,maximum photochemical effciency of PSⅡ and Rubisco activity of Ningmai 13 were less than those of Yangmai 16. Alopecurus japonicus Steud. decreased Rubisco activity of wheat,influenced leaf photosynthetic capacity and energy conversion efficiency,which were the main physiological factor of wheat yield reduction. Under Alopecurus japonicus Steud. stress condition,the response to photosynthetic physiology of Yangmai 16 was more sensitive than that of Ningmai 13. |
基本信息
