Effectiveness of ethylene diurea in ameliorating ozone stress in blackgram varieties (Vigna mungo L.)

Tropospheric ozone, a phytotoxic air pollutant, has inadvertently increased since industrial era and its effect on agricultural crops has gained urgent scientific attention. The present study aims to evaluate the response of blackgram varieties (Vigna mungo L.) exposed to elevated ozone stress (100 ppb) with antiozonant (Ethylene diurea at 300 ppm). The study was conducted during two seasons and the effectiveness of ethylene diurea (EDU) was explored in terms of plant physiology, biochemistry, antioxidant enzymes, growth, yield and spectral reflectance of blackgram varieties. Ethylene diurea ameliorates the ozone stress by increasing photosynthetic rate by 40.78 and 37.21% in season I and 43.03 and 35.77% in season II for VBN3 and VBN8, respectively, and antioxidant enzyme superoxide dismutase by 24.31 and 19.42% in season I and 22.59 and 18.59% in season II for VBN3 and VBN8, respectively. The growth indices and yield traits were significantly increased with the application of EDU and the effect was more pronounced in sensitive cultivar (VBN3) compared to the tolerant (VBN8) one. Spectral reflectance, a non-destructive study, further validates the effect of tropospheric ozone on blackgram varieties. Newly identified spectral indices [R566, R573], and [R564, R586] demonstrated the greatest potential in detecting ozone sensitivity of blackgram varieties.