Identification of pathogenic mycobiota of breeding samples of annual sunflower in the Black Sea Steppe of Ukraine

Abstract

Purpose. Identification of pathogenic mycobiota of breeding samples of annual sunflower in the Black Sea Steppe of Ukraine and preliminary assessment of them as a source material for resistance to a complex of diseases for use in the breeding work.Methods. Material for the study were 23 sunflower hybrids resistant to IMI and SU-herbicides. The resistance of sunflower hybrids to pathogens was evaluated on a natural infectious background.Results. The results of field research of 23 sunflower hybrids, which were located in the collection nursery of the Breeding and Genetic Institute, National Center for Seed Science and Variety Research of NAAS (Odessa) are highlighted. The species composition of sunflower pathogens in the Black Sea Steppe of Ukraine has been established. During the research, leaf spot, phomosis, fomopsis, alternariosis, ascochitosis, septoria were diagnosed, and gray rot, powdery mildew, false powdery mildew (transfer), and rust were identified in adult plants in the flowering – anthodium filling phase. The development of tracheomycosis (verticillium wilt) was diagnosed. Bacterial wilt has also been reported. The most common in sunflower agrocenoses were representatives of the following mycoflora: Phoma helianthi Aleks, Verticillium dahliae Kleb. At the middle level, the saprophytic microflora of Ascohyta helianthi Abramow, Alternaria Nees, Septoria helianthi Ell et Keel occured. Erysiphe cihoracearum Dcf helian, Plasmopara helianthi Novot, Puccinia helianthi Schw, Phomopsis helianthi Munt.-Cwet were found in smaller quantities. Bacteria of the genus Pseudomonas and the basket form Botrytis cinerea Pers were diagnosed in some cases. It should be noted that the species composition of pathogens was different in different varieties of sunflower. In hybrids 'C-10/17', 'C-16/17', 'Sur 1/224', 'Sur 13/200', 'Ex 1008/01', 'Ex 8142/01' it was characterized by a slight damage of false powdery mildew. In hybrids 'C-7/17', 'C 10/17', 'C-12/17', 'Sur 13/243', 'Sur 13/219', 'Sur 13/224', 'PRO-229', 'Subaro', 'C-991', 'HC-2652', 'Ex 1981/01', 'Ex 1008/01', 'Ex8142/01', 'Ex5342/01', 'Ex 1085/01', 'Color' the development of verticillium wilt was observed. Phomosis was quite actively spread in hybrids 'C-7/17', 'C-10/17', 'C-12/17', 'C-16/17', 'C-23/17', 'Sur 13/206', 'Sur 13/243', 'Sur 13/219', 'Sur 13/224', 'Sur 13/200', 'PRO-229', 'С-991', 'НС-2652', 'PR 64 LE99', 'Arkansel', 'Ex 1981/01', 'Ex8142/01', 'Ex 5342/01', 'Color'. Powdery mildew was diagnosed in hybrids 'C-16/17', 'C-23/17', 'Sur 13/206', 'Sur 13/219'. Ascochitosis developed in hybrids 'C-7/17', 'C-23/17', 'Sur 13/206', 'Sur 13/243', 'Sur 13/219', 'PRO-229', 'Subaro' , 'C-991', 'PR 64 LE99', 'Arkansel 6', 'Ex 1981/01', 'Ex 1008/01'. Alternaria spread In hybrids 'C-7/17', 'C-23/17', 'Sur 13/206', 'Sur 13/243', 'Sur 13/219', 'PRO-229', 'Subaro' , 'C-991', 'PR 64 LE99', 'Arkansel 6', 'Ex 1981/01', 'Color'. Septoria was diagnosed in hybrids 'C-23/17', 'Sur 13/206', 'Sur 13/243', 'Sur 13/219', 'PRO-229', 'C-991', 'PR 64 LE99', 'Arkansel', 'Ex 1981/01', 'Color'. Fomopsis affected hybrids 'C-7/17', 'Sur 13/243', 'PRO-229', 'Subaro', 'PR 64 LE99', 'Arkansel', 'Ex 1981/01', 'Ex 1008/01', 'Color'. In individual cases, rust was diagnosed in hybrids 'PRO-229', 'PR64 LE99', 'Ex 1981/42' and bacterial wilt 'Sur 13/206', 'Sur 13/200'.Conclusions. According to the results of the analysis of the degree of damage of the studied selection samples of annual sunflower by pathogens of various diseases it is too early to draw conclusions about complex disease resistance, but for further breeding work in this direction it is possible to select such samples as 'C-10/17', 'C-12/17' , 'C-16/17', 'Sur 13/224', 'Sur 13/200', 'Hc-2652', 'Ex 8142/01', 'Ex 5342/01', 'Ex1085 / 01', which were not affected by rot, various leaf spots, rust, bacterial wilt. Vertical wilting and phomosis were detected in these samples. False powdery mildew was recorded in hybrids 'C-10/17', 'C-16/17', 'Sur 13/224', 'Sur 13/20'. In hybrid 'Ex 8142/01' gray rot and rust were diagnosed on the leaves and anthodium.