Studies on Photosynthesis and Primary Production of Rice Plants in Relation to Meteorological Environments

A semi-empirical model was proposed for the simulation of leaf temperature (Tl), and rates of net photosynthesis (Pn) and transpiration (E) of a single rice leaf in steady-states. The model consisted of two main sub-models: one is for solving the energy balance equations to give E and Tl and another for Pn. In both models the energy and mass transfer processes were expressed in terms of the diffusion resistances, namely, the boundary layer (ra), the stomatal (rs) and the overall mesophyll or residual (rM) resistances. Both the sub-models were thus connected by the resistances and Tl. The diffusion resistances in dependence of wind speed (U), shortwave radiation flux intensity (Is), the leaf temperature (Tl) and ambient humidity were formulated by means of physical and/or empirical equations. By incorporating experimentally specified parameters into the simultaneous equations thus derived, simulations were made to obtain Pn, E and Tl for various environmental conditions.The following results were obtained from the simulations. First, with the increase in the radiation intensity (Is) up to about 0.5cal cm-2min-1, E increased very sharply due to the opening of the stomata, resulting in Tl decrease or only a slight increase, and above this Is level E and Tl both escaped from the stomatal regulations and increased proportionally to Is. The leaf air temperature difference (Tl-Ta) was larger the lower the Ta. Second, three types of curves were derived in photosynthesis (Pn)-radiation (Is) relation, depending on the environmental conditions; a non-saturation type curve at lower Ta, a saturation type curve at near optimal Ta and an optimal type curve at supra-optimal Ta with low humidity. The difference in Pn-Is curve was attributable to Is effect on Tl which in turn reflected on rs and rM. Third, as a result of the response of rs to the leaf air vapour pressure difference, Pn and E at lower humidity were suppressed considerably, resulting in Tl increase. Fourth, with increasing wind speed (U), Pn and E at optimal or above optimal Ta increased, whereas those at sub-optimal Ta decreased. These contradicting effects of U on Pn and E appeared through its effects on ra and Tl.The simulation results were compared with measured data on rice leaves by a leaf chamber method and also with data by other workers. Except for Tl at higher Is and Ta, the model well explained the observed responses in Pn, E and Tl to the environments.

[1]  A. Thom.  The exchange of momentum, mass, and heat between an artificial leaf and the airflow in a wind‐tunnel , 1968 .

[2]  O. Björkman,et al.  Adaptability of the Photosynthetic Apparatus to Light Intensity in Ecotypes from Exposed and Shaded Habitats , 1963 .

[4]  M. Aston.  Variation of Stomatal Diffusive Resistance With Ambient Humidity in Sunflower (Helianthus annuus) , 1976 .

[5]  F.W.T. Penning de Vries,et al.  The simulation of photosynthetic systems , 1970 .

[6]  Tomoshiro Takeda,et al.  An Improvement of Semiempirical Method for Estimating the Total Photosynthesis of the Crop Population : I. On light-photosynthesis curve of rice leaves , 1975 .

[7]  M. Ludlow,et al.  Photosynthesis of Tropical Pasture Plants II. Temperature and Illuminance History , 1971 .

[8]  P. Gaastra,et al.  Photosynthesis of crop plants as influenced by light, carbon dioxide, temperature, and stomatal diffusion resistance , 1959 .

[9]  S. Akita,et al.  Studies on the Differences of Photosynthesis among Species : I. Differences in the response of photosynthesis among species in normal oxygen concentration as influenced by some environmental factors , 1969 .

[10]  D. Koller,et al.  INTERACTIONS OF CARBON DIOXIDE CONCENTRATION, LIGHT INTENSITY AND TEMPERATURE ON PLANT RESISTANCES TO WATER VAPOUR AND CARBON DIOXIDE DIFFUSION , 1967 .

[11]  D. W. Sheriff,et al.  Water Movement into and through Tradescantia virginiana (L.) LeavesI. UPTAKE DURING CONDITIONS OF DYNAMIC EQUILIBRIUM , 1975 .

[12]  K. Ishihara,et al.  The Relationship Between Environmental Factors and Behaviour of Stomata in the Rice Plant : 4. The relation between stomatal aperture and photosynthetic rate , 1972 .

[13]  J. F. Stone,et al.  Oscillatory Transpiration in a Cotton Plant I. EXPERIMENTAL CHARACTERIZATION , 1976 .

[14]  F. S. Nakayama,et al.  Cyclic Changes in Water Balance and Transpiration of Cotton Leaves in a Steady Environment , 1965 .

[15]  Yasuyuki Ishida,et al.  The Relationship between Environmental Factors and Behaviour of Stonlata in the Rice Plant : 2. On the diurnal movement of the stomata , 1971 .

[16]  K. Raschke.  Temperature dependence of CO2 assimilation and stomatal aperture in leaf sections of Zea mays , 1970, Planta.

[17]  H. D. Barrs.  Controlled Environment Studies Of The Effects Of Variable Atmospheric Water Stress On Photosynthesis Transpiration And Water Status Of Zea Mays L. And Other Species , 1973 .

[18]  M. Ludlow,et al.  Photosynthesis of tropical pasture plants i. illuminance, carbon dioxide concentration, leaf temperature, and leaf-air vapour pressure difference , 1971 .

[19]  D. W. Sheriff.  Evaporation Sites and Distillation in Leaves , 1977 .

[20]  B. Drake,et al.  Temperature and transpiration resistances of xanthium leaves as affected by air temperature, humidity, and wind speed. , 1970, Plant physiology.

[21]  E. Barlow,et al.  Photosynthesis, Transpiration, and Leaf Elongation in Corn Seedlings at Suboptimal Soil Temperatures1 , 1977 .

[22]  H. Meidner.  Water supply, evaporation, and vapour diffusion in leaves , 1975 .

[23]  H. van Keulen,et al.  Simulation of water use and herbage growth in arid regions. , 1981 .

[24]  J. Lake.  Respiration of leaves during photosynthesis. II. Effects on the estimation of mesophyll resistance. , 1967, Australian journal of biological sciences.

[25]  P. Chartier,et al.  Resistance for carbon dioxide diffusion and for carboxylation as factors in bean leaf photosynthesis. , 1970 .

[26]  D. M. Gates,et al.  Atlas of Energy Budgets of Plant Leaves. , 1972 .

[27]  E. T. Linacre,et al.  A note on a feature of leaf and air temperatures , 1964 .

[28]  P. Jarvis,et al.  Gaseous-Diffusion Porometer for Continuous Measurement of Diffusive Resistance of Leaves , 1966, Science.

[29]  W. Louwerse,et al.  Photosynthesis, transpiration and leaf morphology of Phaseolus vulgaris and Zea mays grown at different irradiances in artificial and sunlight. , 1977 .

[30]  D. W. Sheriff,et al.  Water Pathways in Leaves of Hedera helix L. and Tradescantia virginiana L. , 1974 .

[31]  A. Frank,et al.  Rates of Photosynthesis and Transpiration and Diffusive Resistance of Six Grasses Grown Under Controlled Conditions1 , 1976 .

[32]  P. Jarvis,et al.  Resistances to Carbon Dioxide and Water Vapour Transfer in Leaves of Different Plant Species , 1965 .

[33]  J. Monteith,et al.  Principles of Environmental Physics , 2014 .

[34]  C. T. Wit,et al.  Simulation of assimilation, respiration, and transpiration of crops , 1978 .

[35]  K. Raschke.  Die Stomata als Glieder eines schwingungsfähigen CO2-Regelsystems Experimenteller Nachweis an Zea mays L. , 1965 .

[36]  J. Parlange,et al.  Boundary layer resistance and temperature distribution on still and flapping leaves: I. Theory and laboratory experiments. , 1971, Plant physiology.