THE VARIATION OF PLANT STRESS INDICATORS AND SOME TRAITS UNDER DIFFERENT IRRIGATION AND NITROGEN LEVELS IN THE ROCKET

摘要

The objectives of this study were to determine the changes of plant stress indicators (relative water content, chlorophyll readings, canopy temperature and spectral indices) and some traits (yield, evapotranspiration, water use efficiencies) under different water and nitrogen levels in rocket (Eruca sativa MILL.). The pot experiment was conducted at two different vegetation periods (VP) under field conditions, in 2013. Four different irrigation treatments were examined (lack of moisture in pot with 3-days interval completed to 100%, 75%, 50% and 25%), in conjunction with 3 different nitrogen (N) applications (7 g m~(-2) N, 14 g m~(-2) N, no nitrogen). Results indicated that irrigation and nitrogen had a significant effect on plant stress indicators and investigated traits. ETday and yield values were obtained at 4.9-9.9 mm and 370-2288 g m~(-2) for VP1 as well as 3.4-7.4 mm and 640-2842 g m~(-2) for VP2, respectively. The coefficient of determination (R~2) values between relative water content and evapotranspiration were 0.91 and 0.88 for VP1 and VP2, respectively. Also, the relationship between the yield and ChlR was seen to be significant (R~2 = 0.87 and 0.90, p＜0.05) in this study. Spectral indices have been used successfully at water deficit and lack of nitrogen. It was clearly seen that canopy temperature was better than other indicators, with regard to the determination of stress dependence on irrigation and nitrogen levels in the rocket.