Using a fixed wing UAV remote sensing system for Sorghum Crop Phenotyping

Remote sensing with Unmanned Aerial Vehicles (UAV) provides great possibilities to acquire images with high spatial and temporal resolution. We obtained remote sensing imagery using a fixed-wing UAV equipped with a multispectral sensor (GEMS, Sentek Systems) for evaluating sorghum (Sorghum bicolor L) crop growth and yield. The UAV was flown over a test field where six hybrids of sorghum were grown in three population densities and in three replications. The altitude for image acquisition was 120 ft. Simultaneously with the UAV flights, we conducted intensive ground sampling for plant leaf area index (LAI) and fractional ground cover (fc). We pre-processed the multispectral data to create orthoimages and extracted Normalized Difference Vegetation Index (NDVI) from each plot. Our results indicate strong linear relationships of NDVI with LAI and fc. The harvesting of test plots will be done in mid-august and the relationship of NDVI with yield will be investigated.