DETERMINATION OF SALT STRESS IN CUCUMBERPLANTS USING VNIR SPECTROSCOPY

摘要

The objective of the study was to determine the energy use of the cucumber plant grown under dif- ferent irrigation salinities by spectroradiometricmeasurements obtained for the different wavelength range of electromagnetic spectrum (EMS). The study was carried out as a randomized complete block experimental design in lysimeter pots in a con-trolled greenhouse environment. Five different salin- ity levels of irrigation water were used and eachtreatment was repeated five times. Throughout the experiment, weekly spectral measurements were collected on leaves by using a handheld spectroradi- ometer capable of measuring a range of 330-1075 nm EMS. In the study, specific wavelength range and index calculations were used to reveal the stress sit- uation of the plant. The results showed that it is pos- sible to determine the plant stress conditions caused by saline irrigation water on cucumber in the 8th, 6th and 8th week of the growing period by obtaining blue, green and red wavelength measurements, re- spectively. Also, salinity stress of cucumber plant can be determined in the 6th week by using Normal- ized Difference Vegetation Index (NDVI) and Vege- tation index (VI) and 9th week for Salinity Index (SI). These results reveal that NDVI and VI index calcu- lations are useful parameters in determining salinity stress of cucumber plant.