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The research was conducted to synthesize and study fungicidal activity of synthesized chemical compounds of various classes, triazole and imidazole, and their mode of action due to the wide spectrum of action and low application rates. The developed synthesis methods resulted in several groups of nitrogen-containing heterocyclic compounds and evaluated their fungicidal activity. Inhibitory activity of compounds to strains of Fusarium solani (medium resistance to fungicides) and Sclerotinia sclerotiorum (susceptible to most fungicides) from the collection of phytopathogenic microorganisms of Agrobiotechnological Department, RUDN University, was tested. In the synthesis of new chemical compounds with fungicidal activity, urea derivatives 1-(3-(Difluoromethyl)-1-methyl-1H-pyrazole-5-yl)-3-(2-chlorophenyl) urea were identified and structurally confirmed. All target compounds were evaluated for their antifungal activity to inhibit mycelium growth. Preliminary screening results showed that all synthesized compounds have good fungicidal activity against S. sclerotiorum . The compound 1-(3-(Difluoromethyl)-1-methyl-1H-pyrazole-5-yl)-3-(3-fluorophenyl) urea showed antifungal activity against S. sclerotiorum . At concentration of 100 ppm, the compound suppressed growth of S. sclerotiorum strain by 90.5 %. An in vitro experiment revealed that the compound 1-(3-(Difluoromethyl)1-methyl-1H-pyrazole-5-yl)-3-(3-fluorophenyl) urea was effective for suppressing white mold - S . sclerotiorum , at the dose of 100 mg/L. The significance of the research lies in the fact that production of eco-safe products in agroindustry is impossible without development of new biologically active compounds with low application rates and toxicity indicators, controlled persistence, corresponding to the world level. The results obtained can be implemented in real sector of economy engaged in production of chemical plant protection products. Synthesis and use of new fungicides are relevant in agricultural production as an element of development and intensification of existing agricultural technologies.

Today, green nanotechnology has great importance due to the presence of different modes of restrictive action against various pathogens such as fungi and bacterial species. The use of nanomaterials has recently increased in agriculture and plant-tissue culture thanks to their unique different properties such as; magnetic, electrical, mechanical, optical, and chemical properties. Optimum use of iron increases protein content in the wheat grain. They also enhance plant growth by improving disease resistance and increase stability of the plants by anti-bending and deeper rooting of crops. It has been reported by many researchers that Nano-fertilizers significantly influenced the seed germination which demonstrated the effect of Nano fertilizers on seed and seed vigor. Chemical methods have been used for the synthesis of nanoparticles. Developing Nano-biotechnology is generating interests in research towards eco-friendly, cost effective and biological synthesis of nanoparticles. Nanoparticles systems have been combined into plant fungal disease controlpractices. Using nanoparticles as biosensors in plant disease diagnostics is also illustrated.

One of the most important limiting factors in spread of apricot in Iran is late spring frost, which damages flower bud and decrease total yield of crop. It has been found that ascorbic acid (AA) plays a beneficial role during plant response to chilling and freezing stresses. To evaluate the effects of AA on alleviating of cold stress, the flower buds of Prunus armeniaca L. cv. Shahroudi were sprayed at pink cluster stage with AS at 4 levels (0, 100, 200 and 300 mg. L-1) and were then exposed to artificial cold stress (4 h at –4 °C) or without cold stress (+ 25°C). Experimental attributes including electrolyte leakage (EL) of flower buds and percentage of damage of pistil, anthers and petals to temperature treatments were determined. The results showed that at - 4°C the lowest and highest percentage of damage and EL of flower buds were observed in application of 200 and 0 mg. L-1 AA, respectively. The highest and lowest percentage of damage of flower organs and EL were obtained in application of 300 and 200 mg. L-1 AA, respectively at + 25 °C. Based on the results of this experiment, AA alleviates the negative effect of cold stress on EL and flower organ damages in apricot cv. Shahroudi, depending on the concentrations of AA used.

Application of salicylic acid (SA) as a phytohormone has been increased due to resistance to stresses such as salt stress. Pot experiments were conducted to determine the effect of exogenous salicylic acid application on growth and ornamental characteristics of calendula grown under salt stress and greenhouse conditions. For this purpose a factorial experiment based on completely randomized design was conducted with 3 levels of SA (0 (control), 1, 2 mM) and 3 levels of NaCl (0, 100 and 200 mM) with 4 replications. At flowering stage, SA was applied with spraying two times in two week intervals. NaCl was also applied as drench (200 ml per pot) in two day intervals. The results showed that salinity decreased the growth, Chlorophyll reading values, flower number per plant and flower diameter. However, foliar applications of SA resulted in greater root, shoot and total dry weight, plant height and leaf area of calendula plants under salt stress. The highest chlorophyll reading values was obtained from 2.00 mM SA application in all NaCl treatments. Salinity decreased number of flower per plant and flower diameter as ornamental characteristics; however SA increased them under salinity stress. Plants treated with 1.00 mM SA had the highest flower diameter at 100 and 200 mM of NaCl. Electrolyte leakage increased by salinity, however foliar application of SA significantly reduced electrolyte leakage under salt stress. Based on the present results, foliar application of SA treatments can ameliorate the negative effects of salinity on the growth and ornamental characteristics of calendula plants.