Effects Of Shading And Waterlogging On Growth And Development Of Winter Wheat In Nanjing

Jiangsu province is the agricultural province of our country, the wheat perennial sowing area of about 2 × 106 hm2, the planting area and total output are all in the first five places in the country. The growth and yield of wheat are affected by genetic factors, environmental conditions and cultivation measures, among which environmental factors such as light, temperature and moisture conditions have a significant effect on the shading due to shading or persistent rain caused by global darkening and waterlogging environment has become an important factor to limit the formation of crop yield and quality. The middle and lower reaches of the Yangtze river are an important grain producing region in China, and it is also a constant rainfall area. In order to study the effects of shading water stress on the photosynthetic characteristics and yield of winter wheat, this study studied the winter wheat experiment with two kinds of experimental methods. The effects of shading,waterlogging and shading and waterlogging on the photosynthetic characteristics and yield of potted wheat leaves at booting stage, flowering stage and grain filling stage were analyzed quantitatively by using different treatment and combination data. The main findings and conclusions are as follows:(1) Potted wheat booting stage, flowering period, filling stage every treatment significantly reduce wheat flag leaf net photosynthetic rate (Pn), and shading wet processing wheat flag leaf net photosynthetic rate was lower in sharpest, wet processing wheat flag leaf net photosynthetic rate, shading treatment was smallest drop in net photosynthetic rate.(2) The stomatal conductance (Gs) of wheat flag leaves was significantly decreased at each growth stage, and the single waterlogging treatment at booting stage had the greatest effect on flag leaf stomatal conductance. The results showed that the single waterlogging treatment had the greatest effect on the stomatal conductance of wheat flag leaves, followed by shading treatment and shading water treatment. The results were consistent with the field test results.(3) Potted wheat booting stage shading treatment, shading waterlogged compound stress of wheat flag leaf intercellular CO2 (Ci) was increased significantly than control, and wet processing flag leaf intercellular CO2 level was significantly lower than control. During the whole flowering period, the effect of the shading treatment on the effect of CO2 concentration on the intercellular level of the flag of the wheat flag was decreased. As the whole grouting treatment period can be seen,waterlogging treatment has the greatest effect on the CO2 concentration of the flag leaves.(4) The treatment of the flag leaf transpiration rate (Tr) was significantly lower than that of the plant experiment, and the water treatment was the most important to the rate of the flag-leaf transpiration rate, and the least of the shading treatment. The effects of the blooming water stress on the wheat flag leaf transpiration rate were the most, and the influence of the sunshade stress was minimal. After the wheat growth and development into the grouting period, the influence of the wheat flag leaf transpiration rate was the most affected by the compound stress of the sunshade, and the influence of the light stress was minimal.(5) Pot experiment of wheat at booting stage and anthesis stage shading were significantly increased wheat flag leaf chlorophyll content (Spad), wet processing to reduce the wheat flag leaf chlorophyll content, shading waterlogged composite stress on wheat flag leaf chlorophyll content also reduced inhibitory effect. The processing of the grouting period significantly reduced the chlorophyll content of the wheat flag,the water treatment was the most influential, and the shading was the least affected.(6) Pot experiment of wheat booting stage, flowering period, grouting period each treatment had no significant effect on panicle number and grain number of the small grain filling period waterlogged, booting stage shading, booting stage, wet processing of small grain grain number basic no effect. Wheat filling stage shading,waterlogged stress influence grain lowest, shading waterlogged compound stress most affected, shading wheat grain slightly higher than the shading wet processing,wet processing than other two kinds of processing of wheat grains. Three stages of treatment significantly reduced the final yield, booting stage minimal impact, filling stage three stress processing, flowering period waterlogged, shading wet processing large influence on yeild.(7) The net photosynthetic rate, stomatal conductance, transpiration rate, and the concentration of carbon dioxide between the cells were reduced in the field experiment. The influence of the light and water combination stress on the Pn value of the wheat flag during the duration of the treatment period was the most significant,and the Pn value of the flag was decreased significantly. The effect of the sunshade treatment on Pn is greater than that of the pre-treatment (2-4d), and the effect of waterlogging stress on Pn is greater than the effect of the sunshade treatment on Pn.Is wet processing, the shading stress influence on stress of the flag leaf of wheat, and significantly reduce the winter wheat flag leaf Pn, Gs, Ci, Tr value, wet processing of winter wheat stress larger late processing. Shading treatment promote the synthesis of chlorophyll, and wet processing and shading wet processing compound stress decreased chlorophyll content of wheat, the consistent with potted flowering period test results. Shading treatment, wet processing and shading waterlogged composite stress led to small grain grain number and grain weight decreased, the final output decreases, the shading waterlogged compound adversity had the greatest influence on winter wheat, shading adversity, waterlogged stress on winter wheat yield minimal impact.Under the condition of pot and field training, shading and waterlogged stress significantly affect photosynthesis and wheat yield, the flag leaf were significantly reduced the Pn, Gs, Tr value and yield, wet processing of potted wheat impact is bigger, may be due to the potted wheat root growth is relatively fragile, the waterlogging.