Weeds - weeds possible pathogens of sunflower

The article presents the results of a survey of wild and weed plants in the Tambov region, many of which until recently were considered ruderal (garbage), growing only in the wasteland and away from sunflower crops, and do not affect the damage to the culture of diseases. It was found that most of the affected grass samples collected in sunflower crops, along the edges of the fields, along the roadsides, along forest belts, reservoirs, on vacant lots and other places of their habitat, belong to the family of Asteraceae. This is yarrow, wormwood, sow Thistle, burdock small, Carduus nutans, common chicory, Thistle field collagen durnishnika, jastrebinka umbrella, common tansy, common cocklebur and amaranth thrown back from the Amaranth family (Amaranthaceae). Botanical features of these herbs are briefly given. Studied and described the symptoms of their leaves and stems. From the fragments of the affected samples, pathogens of diseases common to these herbs and cultivated sunflower were isolated. Isolation of pathogens from the affected organs was carried out in the laboratory according to the generally accepted methods in Mycology and Phytopathology. Their species composition and taxonomic position are established. It was found that the most common pathogen was sunflower Phomopsis - Phomopsis/Diaporthe helianthi Munt. - Cvet. et al. It is noted that the symptoms of Phomopsis, fusariosis, downy mildew, Septoria, ascochitosis and spotting are similar to those on cultivated sunflower. The pathogenic properties of the isolated fungi were determined in laboratory conditions, in accordance with the Koch triad. As a result of artificial infection of seeds and five-day sunflower seedlings with isolates of phytopathogenic fungi isolated from these herbs, their ability to cause infection of various organs of culture has been established. Re-isolation of fungi in all cases showed their complete identity with isolates isolated from natural material. This circumstance allows to draw a conclusion about the possibility of the described herbs to be potential reserves of pathogens for cultivated sunflower.

сорняки, признаки поражения, патоген, проростки, резерватор инфекции, weeds, signs of damage, pathogen, seedlings, infection reserve