Maize transpiration in response to meteorological conditions

Abstract

Differences in transpiration of maize (Zea mays L.) plants in four soil moisture
regimes were quantified in a pot experiment. The transpiration was measured by
the “Stem Heat Balance” method. The dependence of transpiration on air temperature,
air humidity, global solar radiation, soil moisture, wind speed and leaf surface temperature
were quantified. Significant relationships among transpiration, global radiation and
air temperature (in the first vegetation period in the drought non-stressed variant, r =
0.881**, r = 0.934**) were found. Conclusive dependence of transpiration on leaf temperature
(r = 0.820**) and wind speed (r = 0.710**) was found. Transpiration was significantly
influenced by soil moisture (r = 0.395**, r = 0.528**) under moderate and severe
drought stress. The dependence of transpiration on meteorological factors decreased with
increasing deficiency of water. Correlation between transpiration and plant dry matter
weight (r = 0.997**), plant height (r = 0.973**) and weight of corn cob (r = 0.987**) was
found. The results of instrumental measuring of field crops transpiration under diverse
moisture conditions at a concurrent monitoring of the meteorological elements spectra
are rather unique. These results will be utilized in the effort to make calculations of the
evapotranspiration in computing models more accurate.