Evaluation of cherry cultivar susceptibility to bacterial canker and leaf spot disease

Abstract

In this study, the susceptibility of different sweet (19) and sour cherry (3) cultivars (cvs.) to the bacterial pathogens Pseudomonas syringae pv. syringae and P. s. pv. morsprunorum race 1 causing bacterial canker (sensu stricto) and leaf spot was evaluated. Susceptibility to bacterial canker was examined by artificial inoculations of 1‐year‐old rooted trees, which revealed susceptibility of all cvs. to both P. syringae pathovars. Susceptibility level differed among cvs.; sweet cherry cvs. Katalin, Linda, Summit, New Star and Bigarreau Burlat were highly susceptible, sour cherry cvs. Érdi bôtermô and sweet cherry Drogan's Yellow, Carmen, Germersdorfer and Noir de Meched were susceptible. Sour cherry cvs. Španska and Újfehértói fürtös, as well as sweet cherry cv. Rita were found to be less susceptible to bacterial canker. Susceptibility to bacterial leaf spot disease was evaluated on naturally infected (field conditions) and artificially inoculated leaves (laboratory conditions). Severe symptoms of bacterial spot with shot hole appearance were observed in cherry leaves at the beginning of May under field conditions. In all collected leaf samples, presence of P. s. pv. morsprunorum race 1 was determined. Sweet cherries Valery Chkalov, Summit, Bigarreau Burlat and New Star were highly susceptible to this bacterium. No symptoms of bacterial spot were found on sweet cherries Solomary gomboly, Linda, Germersdorfer, Hedelfinger, Katalin, Margit, Carmen, Aida, Sunburst, Alex, Peter, Rita and Kavics and sour cherry Érdi bôtermô. In laboratory conditions, susceptibility of the tested cvs. varied and mostly depended on the inoculation method. Nonetheless, sweet cherry cvs. Carmen and Margit and sour cherry Érdi bôtermô exhibited a certain level of resistance.

Genetic diversity of Pseudomonas syringae pv. syringae isolated from sweet cherry in southern and northern regions in Serbia

“…Due to development of numerous spots on leaves, centres of the necrotic spots drop out giving the leaf a shot hole appearance. The observed symptoms were similar to those caused by plant pathogenic bacterium P. syringae (KENNELLY et al, 2007;SPOTTS et al, 2010;KONAVKO et al, 2014;ILIČIĆ, 2016;BALAŽ et al, 2016;KALUZNA et al, 2016;ILIČIĆ et al, 2018). On NSA medium 2 days after incubation, large, convex, levan-type, mucoid, creamwhitish colonies were mainly formed.…”

“…): syringae, morsprunorum (race 1 and race 2) and cerasi is one of the major disease that affecting sweet cherry production causing significant losses which are expressed through the yield reduction and death of whole trees. Disease is mostly distributed in young sweet cherry plantations worldwide and in Serbian region also (VICENTE et al, 2004;GILBERT et al, 2010;SPOTTS et al, 2010;ILIČIĆ, 2016;BALAŽ et al, 2016;ILIČIĆ et al, 2018ILIČIĆ et al, , 2019.…”

“…Leaf spot symptom on sweet cherry occurs sporadically. During the spring and under cool and wet conditions bacteria from the epiphytic population multiply rapidly, causing brown-purple spots that drop out and produce "shot hole" symptoms (KENELLY et al, 2007;BULTREYS and KALUZNA, 2010;SPOTTS et al, 2010;ILIČIĆ, 2016;ILIČIĆ et al, 2018).…”

“…As one of the most important preventative measures are the production and the use of healthy planting material, compatible rootstocks and cultivars and less susceptible cultivars to pathogen. Chemical control, in general, implies preventive use of fungicides based on copper compounds, but there is a restriction for copper usage, in terms that treatments of stone fruits should only be performed during the dormant period when it is safe for the host (KENNELLY et al, 2007;CARROLL et al, 2010;ILIČIĆ, 2016;ILIČIĆ et al, 2018).…”

Foliar pathogens of sweet and sour cherry in Serbia

“…In intensive cherry plantations and orchards P. syringae pathovars causing bacterial leaf spot are becoming a major problem. Factors that contribute to the occurrence and spread of these pathogens are latently infected planting material, new cultivars, rootstocks, new technology of cherry production as well as the epiphytic nature of the pathogen (Iličić et al, 2018b).…”