[M-TT46] Introducing metaverse to agriculture. Are we ready?

[MTT46-01] Develpment of spectral reflectance data library for the entire growing season of paddy rice based on hyperspectral measurements

*koji sunazaki¹ (1.Department of Cosmosciences, Graduate School of Science, Hokkaido University)

Keywords:paddy rice, hyperspectral reflectance measurement, spectral reflectance library

Hyperspectral reflectance data for the entire growth period of paddy rice plants were collected during rice growing season from June to September 2021 in farmer's fields in the Taisetsu Land Improvement District, Hokkaido. There are many reports on hyperspectral reflectance measurements of rice growth. However, many are often made in laboratory from collected leaves or heads of rice plants. Other reports are the measurements that does not cover the entire growth period. In general, the collection of spectral reflectance data of paddy rice plants is strongly affected by the reflection spectra of soil and field water. The data for early stage of rice growth is particularly challenging to collect where immature rice plants are easily affected by the reflection of the ground surface. In order to avoid the influence of soil and field water surface in the measurement of paddy rice, gradient of -5° to -10° from the horizontal angle was used. It was confirmed that the measurement of hyperspectral reflectance in the early stage of rice growth was possible. Using the same measurement method, a detailed spectral reflectance library was developed for the entire growth period of paddy rice. The characteristic changes in wavelength were captured in the normalized spectral reflectance library. Remote sensing techniques applied by selecting characteristic wavelengths from the spectral reflectance library is expected to be used in high-precision measurements such as estimation of head emergence period, growth status, situations of pest damage, and optimal harvest time.