In the agricultural season of 2022, the sown area under sugar beets remained almost the same as in 2021, expanding, according to Rosstat, by only 2%. The weather in most regions of the cultivation of the root crop favors its growth. To save sugar beet crops from diseases, the company "August" offered farmers an expanded range of drugs that have successfully passed the tests, effectively cope with diseases and increase crop productivity.
The main diseases of sugar beet traditionally include phomosis, fusarium, ramularia, Alternaria, powdery mildew, cercosporosis. However, in Russia today, cercosporosis and powdery mildew are the most common and harmful. These diseases reduce yields, reduce the sugar content of root crops and impair their storage capacity.
The causative agent of powdery mildew develops only on a living plant. White plaque, the main external sign of the disease, consists of the mycelium of the pathogen fungus, spore-bearing outgrowths on it and spores for asexual reproduction - conidia, which give several generations during the season and infect new plants. The fungus is preserved on plant residues, seeds, root crops left in the field from last year. To combat the disease, it is important to observe agricultural technology, but with a high degree of damage, fungicide treatment is the only reliable remedy.
Cercosporosis affects not only sugar beets, but also many other crops and weeds. It appears on the leaves in the form of round brown spots with a red or reddish-brown border. The causative agent hibernates in the form of a mycelium on old tops, on the pericarp of seeds, in uterine roots. The disease develops more strongly in years with alternating dry hot and moderately warm humid weather. Crop rotation plays an important role in the control of cercosporosis, but due to the wide range of host plants of the fungus, the use of fungicides is usually not enough.
“Depending on the climatic features of the season, one of these two diseases usually comes to the fore. The problems faced by farmers are familiar, one might say, planned. Some farms are already carrying out the first preventive fungicidal treatments in the current season. In the south (in Krasnodar and Stavropol) an increase in the consumption rates of fungicides and a reduction in the intervals between treatments are noted, more often it is necessary to resort to a third fungicidal treatment, - says Vladimir Peshekhonov, a leading specialist in the product development department of Avgust Firm JSC in the Central Black Earth Region.
For many years, beet growers have been using such preparations from the August company as Rayok, Benorad, Credo, Kolosal Pro to combat root diseases. However, in recent years, the range of sugar beet protection products has expanded due to the introduction of products based on new, even more effective active ingredients - for example, epoxiconazole and tetraconazole from the thiazole class. These active ingredients are part of the Hecate (difenoconazole + tetraconazole), Rakurs (epoxiconazole + cyproconazole) and Spirit (azoxystrobin + epoxiconazole) preparations. On the basis of azoxystrobin "August" also produces the fungicide "Baly" (propiconazole + azoxystrobin).
“A few words about azoxystrobin: remaining in the wax layer of the leaf, it protects plants from new spores of fungal pathogens. And in combination with triazoles, it is able to stop an already developing infection and stop sporulation in the event of a forced delay in treatment,” notes Vladimir Peshekhonov.
The fungicide "Tirada" (tiram + difenoconazole) also showed its promise. Thiram provides a powerful contact action against pathogenic fungi and bacteria. The most effective prophylactic treatment with this drug is to protect against spores germinating on the surface of the leaf.
Tests of new products have been going on for several years: for example, in experiments on the basis of the All-Russian Research Institute of Sugar Beet and Sugar named after A.L. Mazlumov in the Voronezh region, held in 2017–2019. Fungicides "Gekata", "Spirit", "Baly" and "Tirada" showed high efficiency in comparison with traditional schemes - their use made it possible to increase the yield of sugar beet by 4-5 tons per hectare, as well as increase the sugar content in root crops by 0,5, 2–XNUMX%.
“In dry conditions during the growing season, the best yields were obtained using Balia, 0,8 l/ha and Spirit, 0,7 l/ha. In a wet year, Hecate, 0,8 l / ha, became the most effective against cercosporosis. "Baly", "Spirit" and "Hecate" reduced the spread and development of cercosporosis by about 2 times, powdery mildew - by 4-5 times compared to the control without treatment," summarizes Vladimir Peshekhonov.
The specialists of "August" recommend using the above fungicides with the adjuvants "Allur" or "Polyphem", so that the solution of the drug spreads better over the leaf, more effectively fixed on it and quickly begins to act on the pathogen.