Plant growth and productivity are often limited by high root-zone temperatures (RZT) which restricts the growth of subtropical and temperate crops in the tropics. High RZT temperature coupled with low growth irradiances during cloudy days which mainly lead to poor root development and thus causes negative impact on the mineral uptake and assimilation. However, certain subtropical and temperate ...

The aim of this work was to analyse the response of NH4 + assimilation in leaves of tobacco plants (Nicotiana tabacum L. cv. Tennessee 86), to different B applications (B1, 5 M H3BO3; B2, 10 M H3BO3; B3, 20 M H3BO3). The plants were grown under controlled environmental conditions and received a complete nutrient solution. In this experiment, we analysed the foliar concentrations of B and NH4 , ...

Crop plant development is strongly dependent on the availability of nitrogen (N) in the soil and the efficiency of N utilization for biomass production and yield. However, knowledge about molecular responses to N deprivation derives mainly from the study of model species. In this article, the metabolic adaptation of source leaves to low N was analyzed in maize (Zea mays) seedlings by parallel m...

Evapotranspiration (ET) is an important component of the hydrologic budget because it expresses the exchange of mass and energy between the soil-water-vegetation system and the atmosphere. Prevailing weather conditions influence potential or reference ET through variables such as radiation, temperature, wind, and relativity humidity. In addition to these weather variables, actual ET (ETa) is al...

An Ensemble Kalman Filter (EnKF) is used to assimilate canopy reflectance data into an ecosystem model. We demonstrate the use of an augmented state vector approach to enable a canopy reflectance model to be used as a non-linear observation operator. A key feature of data assimilation (DA) schemes, such as the EnKF, is that they incorporate information on uncertainty in both the model and the o...

To improve crop model performance for regional crop yield estimates, a new four-dimensional variational algorithm (POD4DVar) merging the Monte Carlo and proper orthogonal decomposition techniques was introduced to develop a data assimilation strategy using the Crop Environment Resource Synthesis (CERES)-Wheat model. Two winter wheat yield estimation procedures were conducted on a field plot and...

Salt-alkaline stress generally leads to soil compaction and fertility decline. It also restricts rice growth and phosphorus acquisition. In this pot experiment, two relatively salt-alkaline tolerant (Dongdao-4 and Changbai-9) and sensitive (Changbai-25 and Tongyu-315) rice genotypes were planted in sandy (control) and salt-alkaline soil to evaluate the characteristics of dry matter and phosphor...