Researchers from the University of Florida Institute of Food and Agricultural Sciences, the U.S. Department of Agriculture and NASA have developed a hyperspectral imaging approach that can detect drought stress in lettuce plants days before visible symptoms appear, offering potential benefits for controlled environment agriculture and future space missions.

The findings, published in Plant Phenomics, showed the technology identified plant stress shortly after watering was reduced, allowing growers to respond before plants began to wilt or change color. Researchers said earlier detection could improve irrigation management in greenhouses and other indoor production systems where crops depend on carefully controlled conditions.

The system uses hyperspectral imaging to scan how leaves reflect light across a wide range of wavelengths beyond what the human eye can see. By measuring subtle physiological changes without damaging the plants, the technology provides a faster and more precise method of identifying drought stress.

Researchers detected drought stress within a few days of reduced watering, with the system reaching about 97% accuracy by the fifth day. The technology also consistently identified drought stress across multiple independent experiments, suggesting it could perform reliably under different growing conditions.

The research was designed in part to support future space exploration, where automated crop monitoring will be essential because plants must be grown with limited water and other resources. Scientists said systems capable of continuously monitoring plant health without constant human oversight could help support food production during missions to the moon or Mars.

Although developed with space applications in mind, the technology also could benefit commercial greenhouse operators and other controlled environment agriculture systems. Early detection of drought stress may allow growers to adjust irrigation sooner, improve water use efficiency and reduce crop losses.

Researchers also said the approach could eventually be adapted to detect other forms of crop stress beyond drought by combining hyperspectral imaging with artificial intelligence, expanding its potential use for precision crop management.

Source: University of Florida, "From fields to space farming, new tool detects crop drought stress before it's visible"