Effects Of Meteorological Conditions On Photosynthetic Characteristics And Maize Yield

In order to study the effects of meteorological conditions on photosynthetic characteristics and yield of maize,using the experiment on medium-late variety "ZD 958"of maize which were planted on large areas of Liaoning Province,was conducted in the scientific research and experiment base of Agricultural College in Shenyang Agricultural University in 2015 and 2016.Through the method of sowing to simulate different meteorological conditions,and using statistical analysis methods to investigate the effects of meteorological factors on photosynthetic characteristics and grain yield of maize;sowing period analysis method to explore the difference between photosynthetic characteristics and grain yield of maize by variance.The main results are as follows:1.Temperature,light intensity and relative humidity are the meteorological factors influencing the net photosynthetic rate significantly,jointing temperature within a certain temperature range,the higher the light intensity is stronger,larger relative humidity and high temperature and large cumulative sunshine hours will have a role in promoting the growth stage,the photosynthesis;the higher the temperature is,the bigger the cumulative precipitation inhibited the net photosynthetic rate of growth.2.The influence degree of stomatal conductance is vulnerable to the weather conditions,the growth stages of maize in a certain range of temperature and light intensity increase will increase the inhibition of stomatal conductance,the increase of the relative humidity will contribute to the different growth stages of the accumulation of meteorological conditions on the impact of stomatal conductance small.3 At the jointing stage,the temperature and relative humidity increase of intercellular CO2 concentration play a role in promoting,the light intensity increase to have a certain effect;at the growth stage,temperature and light intensity is the inhibitory factor of intercellular CO2 concentration,and relative humidity plays a role in promoting the earlier,the cumulative effect of meteorological conditions on it is not very significant.4 Real time maize transpiration rate and the whole growth stage,the real-time temperature,light intensity and the sunshine duration was positively correlated with these factors increase the transpiration increased;in a certain extent,the whole growth period of relative humidity,pre accumulated temperature and the accumulated water drop on transpiration rate to suppress effect.5 The diurnal variation of net photosynthetic rate and transpiration rate showed a single peak curve,which increased first and then decreased,and the peak value appeared at 11 or more.The net photosynthetic rate and transpiration rate decreased with the advance of the growth process.The diurnal variation of temperature,light intensity is increased first and then decreased,the individual time points due to weather conditions cause abnormal temperature and light intensity increased or decreased;the relative humidity change trend is upward trend,due to the processing of numerical varies,and the result is irregular.The peak value of net photosynthetic rate appeared at the time of peak intensity of light intensity,and the net photosynthetic rate was different because of the same intensity.In addition to the influence of light intensity and temperature,the relative humidity is an important factor affecting transpiration rate.6 During the whole growth period,accumulated temperature and the accumulated precipitation had significant effect on yield,within a certain range,the higher temperature of the accumulated precipitation is bigger,more can increase the yield of maize;cumulative precipitation and ear diameter and bald length have significant negative correlation,sunshine duration and ear diameter and length of bald a significant positive correlation.