Test Study On Canopy-air Temperature Difference For Winter Wheat Irrigation Index

Take to October 2010 to October 2011 the north China north plain grain and economic crop of winter wheat field experimental data as the basis,measurement of crop soil moisture index and physiological index,and analysis of the indicator indicates the ability of the crop water status,the relationship between,and then can be used to guide the irrigation of Winter Wheat and soil moisture index and canopy air temperature difference index.The main results are as follows:(1)The different water treatments on winter wheat morphology has an obvious effect.In under the different water treatment,winter wheat in different growth period photosynthetic rate,transpiration rate,stomatal conductance and canopy air temperature difference have obvious differences,diurnal fluctuation is bigger,but the peak is more concentrated in the 10:00?14:00.(2)The winter wheat photosynthetic rate,transpiration rate,stomatal conductance and soil moisture index have significant positive correlation;photosynthetic rate,transpiration rate,stomatal conductance and temperature difference is a curve correlation.(3)Soil moisture,winter wheat canopy-air temperature difference and water use efficiency for curve,jointing stage of winter wheat soil moisture accounted for about 65%of field capacity,booting and flowering period accounted for about 70%,accounting for about 55%of the milk stage,jointing stage canopy-air temperature difference of 0?,booting and flowering stage period of canopy-air temperature difference of 1.5?,milk ripe stage canopy-air temperature difference of 1?,water use efficiency,can use less water to obtain high yield,can be used as the irrigation control index crops.