The Behavior of Some Sunflower Hybrids to White Rust (Albugo tragopogonis) under Brăila County Conditions

Abstract

As a part of an extensive study on the behavior of different genotypes of sunflower to solid and liquid fertilizers and plant protection products to the attack of the main parasitic agents, this paper presents the dynamics of Albugo tragopogonis. Symptoms during the asexual phase were expressed, symptoms that became visible as white pustules on the infected plants. Although the tested fungicides were not approved to control this pathogen, a reduction in the development of the pathogen have been observed in the variants where have been applied the fungicides. The best percentage calculated for effectiveness was the fertilization variant Last N (250 g/l N) in two doses where was applied the fungicide Tanos WG (0.4 kg/ha) with 86.96%, followed by the variant Urea 46% N (90 kg/ha a.s.) where was applied the fungicide Sfera 535 SC (0.4 l/ha) with an effectiveness of 78.26%. Even if in 2019 no genotype of the sunflower under study showed symptoms, in 2020 all nine hybrids showed symptoms with different frequencies and intensities. The impact of white rust on Romania commercial sunflower crops has not been determined. Research needs to be done to find possible seed treatment that will keep the disease at bay and protect the sunflower crops.