M. S. Gvozdeva1, G. V. Volkova1, A. G. Izvarina1, I. A. Zhuyko2
1Federal Research Center of Biological Plant Protection, Krasnodar, p/o 39, 350039, Russian Federation
2M. Yu. Lermontov Lyceum No. 90, ul. 7-letiya Oktyabrya, 28, Krasnodar, 350089, Russian Federation
Abstract. The research aimed to study the biological effectiveness of fungicides of the triazole group (Magnello, EC (emulsion concentrate), 100 g/l difenoconazole + 250 g/l tebuconazole; Capella, OE (oil emulsion), 30 g/l difenoconazole + 120 g/l propiconazole + 60 g/l flutriafol; Kolosal Pro, OEC (oil emulsion concentrate), 300 g/l propiconazole + 200 g/l tebuconazole) against the causative agent of wheat leaf rust and their effect on the intrapopulation structure of the pathogen. The work was carried out under the conditions of a climatic chamber Binder KBWF 720 on a susceptible variety of winter wheat Krasnodarskaya 99. A decrease in the sensitivity of the North Caucasian population of the pathogen P. triticina to the fungicide Colosal Pro, OEC was established. The value of the CK95 indicator (lethal concentration) was 443.9 mg / ml, which is 2.3 times more than the recommended concentration in the process solution. The efficacy of Magnello, EC was high, but CK95 (410.1 mg/ml) was also high. The values of CK50 and CK95 (105 mg/ml and 199.5 mg/ml, respectively) closest to the recommended concentration in the process solution were observed for the fungicide Capella, OE – 76.9 mg/ml and 210.9 mg/ml, which indicates high sensitivity of the P. triticina pathogen population to the toxicant. With an increase in the rate of drugs use, the average virulence of the population decreased. In the variant with the maximum rate (200% of the recommended) of Capella, OE, it was 25.8%, Magnello, EC – 27.4%, Colosal Pro, OEC – 29.0%. Based on the analysis of the phenotypic composition of the P. triticina population under the influence of fungicides of the triazole group, 9 highly virulent phenotypes were identified: MHTTQ, THTTS, RKTTT, MKTTT, RHTTT, RHTTR, THTTT, PHTTT, MHTTT.
Keywords: winter wheat (Triticum aestivum L.); brown (leaf) rust (Puccinia triticina); virulence; fungicides; triazoles; susceptibility.
Author Details: M. S. Gvozdeva, research fellow; G. V. Volkova, D. Sc. (Biol.), corresponding member of the RAS, chief research fellow, head of laboratory (e-mail: Этот адрес электронной почты защищён от спам-ботов. У вас должен быть включен JavaScript для просмотра.); A. G. Izvarina, research assistant; I. A. Zhuyko, schoolboy.
For citation: Gvozdeva MS, Volkova GV, Izvarina AG, et al. [Susceptibility of wheat leaf rust pathogen to triazole group fungicides]. Dostizheniya nauki i tekhniki APK. 2022; 36(12):30-4. Russian. doi: 10.53859/02352451_2022_36_12_30.