Applying hyperspectral imaging to explore natural plant diversity towards improving salt stress tolerance

- Salinity represents an abiotic stress constraint affecting growth and productivity of plants
- Better solutions is to improve the level of salt resistance using natural genetic variability within crop species
- Phenomic methodology employing different non-invasive imaging systems for detecting quantitative and qualitative changes caused by salt stress at the whole plant and canopy level. Hyperspectral imaging techniques provide unique opportunities for fast and reliable evaluation of numerous characteristics associated both with various structural, biochemical and physiological traits
- Salt-soil-plant interaction and sustainable coastal agriculture need powerful phenotyping tools

Salinity represents an abiotic stress constraint affecting growth and productivity of plants in many regions of the world. One of the possible solutions is to improve the level of salt resistance using natural genetic variability within crop species. In the context of recent knowledge on salt stress effects and mechanisms of salt tolerance, this review present useful phenomic approach employing different non-invasive imaging systems for detection of quantitative and qualitative changes caused by salt stress at the plant and canopy level. The focus is put on hyperspectral imaging technique, which provides unique opportunities for fast and reliable estimate of numerous characteristics associated both with various structural, biochemical and physiological traits. The method also provides possibilities to combine plant and canopy analyses with a direct determination of salinity in soil. The future perspectives in salt stress applications as well as some limits of the method are also identified.

Examples of the structural reflectance parameters derived from hyperspectral imaging of soybean leaves treated with salt stress. a) and b) are leaves from non-salt conditions and c) and d) are leaves from plants treated with 250 mM NaCl concentration. Pictures of a) and c) show the soybean leaf of genotype SA-108 and b) and d) shows the soybean leaf of genotype SA-136. Leaves (c) shown a typical symptomatic of damage induced by salt stress conditions163