Gene

Biology

Downy mildew

Sunflower

Botany

Genetics

Regional science

Veterinary medicine

Russian federation

Geography

Sociology

Horticulture

Medicine

Race (biology)

Virulence

Plant Protection Science

Sunflower downy mildew caused by Plasmopara halstedii (Farl.)Berl.et de Toni is a destructive and widespread disease.More than 50 races of P. halstedii have been recorded worldwide.In 2020, in the Russian Federation (Zernogradsky district, Rostov region), a globally new race 337 was identified for the first time.The pathogen was identified on the plants of a foreign sunflower hybrid bearing the resistance gene Pl 6 .According to the five-digit racial nomenclature, its virulence profile was determined as 337 53.It is the first P. halstedii race recorded in the Russian Federation that simultaneously infects all differential lines of the 3 rd triplet, i.e., HA-R4, HA-R5 and HA-335.The sunflower lines RHA-274, 803-1, PSC8, RHA-419 and RHA-340 were resistant to it.All the collected isolates of the new race were susceptible to the fungicide mefenoxam.

The first report of Plasmopara halstedii race 337 in the Russian Federation