The effect of foliar application of iron, zinc and manganese nano-chelates on growth and biochemical indicators of peppermint (Mentha piperita L.)

Nowadays, the use of nano-fertilizers is of great importance in order to reduce the losses of nutrients and increase the quantity and quality of medicinal plants is great importance. To investigate the effect of foliar application of iron, zinc and manganese nano-chelates (Zero, 2, 4 and 6 mg/l) on the growth and biochemical indices of peppermint (Mentha piperita L.) in a completely randomized design with three replications, Located in Gorgan city, it was carried out in 2021, the plants were foliar-sprayed from the four-leaf stage in three stages with a time interval of 10 days, and after two weeks of the last foliar spray, sampling and trait evaluation was done in the flowering stage. The results showed that the treatments had a significant effect on the evaluated traits, so that the highest fresh and dry shoot weight, plant height, total chlorophyll content, iron content and essential oil content in the treatment of 6 mg/l iron nano-chelates and the highest fresh and dry weight of roots and amount of plant zinc were obtained in the treatment of 6 mg/l zinc nano-chelates, also in the treatment of 6 mg/l manganese nano-chelates, the highest content of phenol, flavonoids and manganese was observed. Overall, the results showed that the application of 6 mg/l nano-chelates of iron, zinc and manganese positively increased peppermint's morphological and biochemical traits.