Crop water stress index of beans

Abstract

A sustainable future requires efficient water use in irrigated agriculture to ensure food and water security. The crop water stress index (CWSI) is a remote sensing tool that can help achieve this goal. In typical CWSI experiments, infrared sensors focus on the canopy to measure its temperature. This study evaluated this methodology for crop beans (Phaseolus vulgaris L.) with low canopy coverage. In this scenario, the temperature measurement is significantly affected by the presence of straw mulch. The study also proposed a procedure that uses supplementary data to estimate canopy coverage and straw mulch temperature. Then, the canopy temperature is finally estimated from the infrared sensor measurement. The procedure was successfully implemented for low canopy coverages. Without it, the baseline slope was inconsistent with the CWSI theory. This was particularly true during the earlier phenological stages. The lowest observed canopy coverage was 0.17 for the baseline and 0.26 when estimating the CWSI. The CWSI showed a clear relationship with soil water content.