Nasser Ibrahem. (1) (2)*, Mohamud Abd-Alaziz (3) and Yahua Mohamad(3)
- General Organization of Remote Sensing, Damascus, Syria.
- Department of Field Crops, Faculty of Agriculture, Tishreen University,
Lattakia, Syria.
(*Corresponding author: Dr. Nasser Ibrahem E-Mail: nibrahem345@gmail.com)
Received: 4/07/2020 Accepted: 17/08/2020
Abstract
This research is based on the use of remote sensing through spectroradiometric devices in studying the spectral signature (within the wavelength range 350-2500 nanometers at every 1 nm) of the coriander plants that treated with different concentrations of bread yeast (0, 2, 4 and 6%) during three sprinkle times (42, 56 and 71 day from planting of season 2019) in Al-Safsafah region of Tartous. Then the productivity was estimated at any growth stage depending on spectral mathematical models derived from the spectral reflectance values that recorded during the growth stages. The spectral models were tested among them for the yield estimate. The results showed that the spectral reflectance values of the plants sprayed with yeast at the concentration of 6% were the highest in the near and far infrared range (700-1300 nm) and in the green range (475 -510 nm), while reflectance in the red range (670 nm) is the lowest. Then, the spectral reflectance values of the plants treated with the lower concentrations decreased from 4% to 2% and then the control in the near and far infrared ranges and the visible green, while the reflectance in the red range increased starting from the control to the highest spray concentration (6%). The increment in the number of spray had maintained the curve of spectral reflectance values that recorded within each concentration for longer period, but with the low reflectance rate within each spectral range, with the age of the crop. So, the increase of the number of times during growth stages led to vigor extension of plant tissues and therefor more yield. The spectral models of one or/and multi-stages had been developed and tested for yield prediction. The best model was the spectral difference index (NR) model depending on multi-stages values of (NR) associated with 42, 56 and 71 days after sowing. The spectral mathematical modeling process of multivariate stages showed the changes resulting from the interaction of the agricultural conditions with the climate factors experienced by the plant during the growth stages on the productivity, so the results suggested to use the spectral multi-stages data of remote sensing in yield predicting models.
Keywords: Spectral modeling, Spectral difference index, Bread yeast, Coriander, Productivity.
Full paper in Arabic: PDF