A portable Hyperspectral imaging system to assess the effect of different nutrient management practices on Chamomile (Chamomila recutita)

Chamomile (Chamomila recutita) is a native species of Europe and Asia which globally cultivated with 8000 tons annual production. It has antioxidant, antimicrobial and anti-inflammatory properties, and has a huge demand in cosmetic, food, pharmaceutical and healthcare industries. Such a high demand can be met through effective nutrient management during crop cultivation monitored for assessment of its effect on the crop health and vigor. Traditional methods of nutrient monitoring during the crop growth phase are invasive and time consuming, hence the use of advanced sensors like Hyperspectral can be an effective tool for non-invasive crop health monitoring. In the present study, the effect of different nutrient treatments including microbial culture and micronutrients on chamomile crop were investigated using portable hyperspectral camera (4001000 nm). Various Hyperspectral Vegetation Indices (VIs) based on normalized differences (NDVI, RDVI, MSR), soil contrast adjustment (SAVI, MSAVI, OSAVI), simple ratio of two discrete bands (SR, GRVI, Red-edge) and three discrete bands (MCARI, TCARI, TVI, SIPI) over multiple nutrient treatments were calculated and were compared to characterize the crop growth status, biophysical variability, vigour, Leaf Area Index (LAI) and pigments like chlorophyll & carotenoids. Results show that Renormalized difference vegetation index (RDVI) and Normalized difference vegetation index (NDVI) are best for discriminating amongst different nutrient management practices. The study illustrates the usage of portable Hyperspectral sensor as an effective non-invasive instrument for nutrient management and crop health assessment.