Background: Peppermint with the scientific name of Mentha piperita L. is used for
pharmaceutical purposes and food industry. Cultivation of this plant is
economically important due to its ability to produce and store essential oils.
Although the production of secondary metabolites in medicinal and aromatic plants
is mainly influenced by plant genetics, their biosynthesis is strongly influenced by
environmental factors. The use of micronutrients in the form of foliar application,
especially in alkaline soils (which are often deficient in micronutrients), is a suitable
and effective method to increase the factors affecting the quality and yield of
essential oils of medicinal plants.
Aim: This study was conducted to investigate the effect of amount and frequency
of NPK nano fertilizer foliar application on quantitative and qualitative yield of
peppermint in climatic conditions of Bushehr province.
Methodology: he experiment was performed as a factorial experiment in a
completely randomized design in 4 kg pots and in the open with three replications.
Factors studied include foliar application of different amounts of NPK nano
fertilizer (20-20-20) and ordinary NPK fertilizer (20-20-20) in two concentrations
(2 and 4 per thousand), control treatment (no fertilizer application) and frequency
of foliar application (one It was applied twice, three times and three times) in the
early stages of plant growth, in the middle of the growing season and before
flowering. The studied traits included plant height, number of leaves, leaf area, fresh
and dry weight of the plant, chlorophyll index, percentage of essential oil and
amount of N, P and K elements.
Conclusions: The results showed that the independent effect of fertilizer type,
frequency of foliar application and the interaction of these two factors were
significant for all studied traits of peppermint. The results obtained in this study
showed the positive effect of NPK fertilizer application in both conventional and
nano for