Biophysical observations, including fresh and dry biomass and plant height, were acquired once every week by destruc- tive sampling. VWC was derived by computing the difference between the fresh and dry biomass. Total LAI was measured using a LAI-2000 (LI-COR, Lincoln, NE), which is an indirect method for estimating total LAI [19]. NDVI of the rice canopy was derived using measurements provided by an active optical sensor (Greenseeker, RT 100 model # 505, NTech Inc.). This sensor uses light-emitting diodes to generate red (wavelength of 656 nm) and near-infrared (wavelength of 774 nm) light. The reflected light from the crop is measured by a photodiode located at the front of the sensor head. The NDVI sensor was hand carried through the field. Measurements were made at nadir position (∼0.8 m) directly above the rice canopy for nine points in the field.