Abstract:
The objective of this research was to apply drone mapping aerial imagery for precision variable rate nitrogen and yield estimation using NDVI on modern maize cultivation by using multi-spectral reflection in red light at a wavelength of 668 nm and near-infrared at a wavelength of 842 nm.
The research was conducted in Wang Noi district, Phra Nakhon Si Ayutthaya province, starting from June to November 2021. The experimental area is 12,467 m2, divided into two plots, A and B. Each plot has 99 blocks, and each block has a size of 6x10 m2/block.
The research results were obtained from the data collected on the two plots of land by considering the samples based on the five levels of completeness of the maize canopy in the range of 50-100%. It was found that the relationship between the NDVI value and the weight of maize seeds can estimate the yields when maize is aged in the range of 65-82 days. This is because the correlations between the NDVI values and the weights of maize seeds were in the same direction with a correlation of 78% at a confidence level of 95% and R2 of 61%. For the linear regression statistical analysis, the equation was Y = 0.67X - 30.927. When estimating yields on the total area, it was found that the maize yield estimation using aerial imagery combined with NDVI of plot A and plot B had errors of 1.75 and 1.67%, respectively.