Total phenolic content (mg GAE/g)
Total phenolic content was significantly affected by application, dose, period and their interactions. The highest value was found in the 2nd period of nano-ZN-125 ppm application, while the lowest value was found in the 3
rd period of nano-IR-200 ppm application. In terms of efficiency, nano-MO-125 ppm > nano-BO-200 ppm > nano-ZN-125 ppm > nano-IR-125 ppm (Table 1). Application of all fertilizer types at 125 ppm yielded better results than the application at 200 ppm. These findings are supported by a similar study carried out by
Bleidere et al., (2013).
Total flavonoid content (mg QE/g)
Total flavonoid content was significantly affected by application, dose, period and their interactions. The highest value was found in the 2
nd period of nano-ZN-125 ppm application, while the lowest value was found in the 3
rd period of nano-IR-200 ppm application (Table 1). It is apparent that 125 ppm nanofertilizer is more effective than 200 ppm nanofertilizer. Nanofertilizers can be utilized to enhance plant growth and development and when used adequately, nanofertilizers can be useful in increasing the production of flavonoid compounds in plants, thus enhancing their immunity against diseases, pests and environmental stressors.
Total antioxidant content at (%)
The distributions of total antioxidant content were statistically different in terms of application, dose, period, dose*period, application*dose, application*period, application*dose* period, year*application and year*application*period*dose interactions (p<0.01). Examining the averages for two years, the highest value was obtained from 3
rd period of nano-ZN-125 ppm application to be 87.22±4.58%. The lowest value was obtained from 3
rd period of nano-MO-200 ppm fertilizer to be 60.39±2.54% (Table 1). Nano-BO and Nano-IR 200 ppm nanofertilizer is more effective than 125 ppm nano fertilizer. The opposite applies to others.
Proline (µg/ml)
Proline distributions were affected by application, dose, period and their interactions. The highest value was found in the 3
rd period of nano-BO-125 ppm fertilizer, while the lowest value was found in the 1
st period of nano-BO-125 ppm fertilizer. Nano-BO-200 ppm is more effective than 125 ppm (Table 2).
Poustini et al., (2007) found that salt stress applications caused an increase in proline levels in leaf tissues in 30 bread wheat cultivars. Other studies have also shown that proline levels increased in tomato (
Doğan and Tipirdamaz, 2010) and corn (
Yakıt and Tuna, 2006) plants under salt stress.
Catalase activity (CAT) (EU/mg protein)
Catalase activity was affected by application, dose, period and their interactions. The highest value was found in the 3
rd period of nano-BO-125 ppm fertilizer, while the lowest value was found in the 1
st period of nano-BO-125 ppm fertilizer. Nano-O-200 ppm is more effective than 125 ppm (Table 2).
Ascorbic acid peroxidase activity (APX) (EU/mg protein)
APX distribution was affected by application, dose, period and their interactions. The highest value was found in the 3
rd period of nano-BO-125 ppm fertilizer, while the lowest value was found in the 1
st period of nano-BO-125 ppm fertilizer (Table 2).
Lipid peroxidation activity (MDA) (nmol/ g TA)
MDA levels were affected by application, dose, period and their interactions. The highest value was found in the 3
rd period of nano-BO-125 ppm fertilizer, while the lowest value was found in the 1
st period of nano-BO-125 ppm fertilizer (Table 2). Chattha
et al. (2022) found that potassium reduced MDA and oxidative damage in tomato plants under salt stress. The results achieved in this study are consistent with their findings.
Total chlorophyll content (mg/g)
The total chlorophyll content was affected by application, period and dose. The highest value was found in the 1
st period of nano-IR-200 ppm application, while the lowest value was found in the 3
rd period of nano-ZN-200 ppm fertilizer application. Nano-IR, nano-ZN, nano-MO and nano-BO were observed to be advantageous in that order (Table 3). The results reported by
Kumawat et al., (2006), Ashrafuzzaman et al., (2000) and
Turan et al., (2009) are also consistent with the results reported in the present study.
Chlorophyll-a (mg/g)
Chlorophyll content was affected by application, period, dose and year in the first year. In the 2
nd year, only application, period and dose were significant. Upon examining the averages for 2 years, the highest value of 5.47±2.61 mg/g was found during the 2
nd period of applying nano-IR-200 ppm. The lowest value of 0.97±0.13 mg/g was obtained during the 3
rd period of applying nano-ZN-200 ppm fertilizer (Table 3). Nano-IR was found to be more useful when compared to Nano-ZN, Nano-MO and Nano-BO in terms of fertilizer types. Insufficient fertilizer results in plant stress. Hence, findings reported in previous studies on stress align with the results achieved in this study (
Agastian and Kingsley, 2000;
Kaya et al., 2003).
Chlorophyll-b (mg/g)
The chlorophyll content was significantly affected by application, period, dose and their interactions. The highest value was found in the 2
nd period of nano-IR-200 ppm application, while the lowest value was found in the 3
rd period of nano-ZN-200 ppm fertilizer application. Nano-IR was found to be more useful than Nano-ZN, Nano-MO and Nano-BO. Upon examining the averages for 2 years, the highest value of 5.47±2.61 mg/g was found during the 2
nd period of applying nano-IR-200 ppm. The lowest value of 0.97±0.13 mg/g was obtained during the 3
rd period of applying nano-ZN-200 ppm fertilizer (Table 3). Nano-IR was found to be more useful when compared to Nano-ZN, Nano-MO and Nano-BO in terms of fertilizer varieties. Insufficient fertilizer results in plant stress. Hence, findings reported in previous studies on stress align with the results achieved in this study (
Agastian and Kingsley, 2000;
Kaya et al., 2003).
Total carotenoid content (mg/g)
The carotenoid content was significantly affected by application, year*application and year*application period*dose interactions. The highest value was found in the 2
nd period of nano-IR-200 ppm application (3.60±2.82 mg/g), while the lowest value was found in the 3
rd period of nano-ZN-200 ppm fertilizer application (0.16±0.06 mg/g). Nano-IR was found to be more useful than nano-ZN, nano-MO and Nano-BO (Table 1). The present findings are supported by the results of a study carried out by
Yakit and Tuna (2006).