Seasonal variation in susceptibility of apricot to Pseudomonas syringae pv. syringae (bacterial canker), and site of infection in apricot and cherry

Abstract

The seasonal variation in susceptibility of buds, stems, leaves and fruit of apricot to Pseudomonas syringae pv. syringae, and sites through which infection occurs in apricot and cherry were studied. Infection of apricot and cherry occurred through buds, flowers, leaves, fruit and stems but not leaf scars through which natural infection can occur. Only stem and bud inoculations consistently led to the establishment of cankers. The proportion of buds showing infection was highest with inoculations made in late autumn and winter (May-July), and lowest with inoculations in summer (December-February). The number of stem inoculations, resulting in extensive cankers, was highest in late winter and spring (August-November) and lowest in summer and early autumn (December- March). Leaves and fruit were susceptible only during spring (September-November), when they were immature. The importance of these findings in relation to epidemiology and control of bacterial canker is discussed.

Epidemiology of Pseudomonas syringae Pathovars Associated with Decline of Plum Trees in the Southwest of Germany

“…During leaf fall, leaf scars appear to be an important infection site for P. syringae at least in cherry trees (Crosse, 1956, 1957; Bech, 1992). On the other hand, Wimalajeewa (1987) reports that apricot and cherry are not infected by Pss through leaf scars, even when the leaves are removed forcibly, although stem and bud inoculations with the same Pss isolate consistently lead to the establishment of cankers. In the experiments reported here, Pss did not lead to more necrotic buds than mock inoculation, no matter whether the formation of an abscission layer was stimulated or not (Table 5).…”

Quantitative and qualitative seasonal changes in the microbial community from the phyllosphere of sugar beet (Beta vulgaris)

“…It was detected early in the season on young plants but was rarely isolated during summer months. Wimalajeewa (1987) also observed reduced P. syringae numbers during warmer months and attributed this to susceptibility to low humidity, high temperatures and ultra violet radiation. Some P. syringae are known to catalyse ice formation at temperatures close to 0°C and although this was not examined in the present study, P. syringae was isolated most commonly (42.9% of the mature leaf bacteria community) on day 272, after exposure to severe frost.…”

Fractionation and Speciation of Cu in Different Processing Apricots

“…The apricots were collected from 10 trees of the Kabaaşı variety that were treated with Bordeaux Mixture (BM) before harvest and another 10 trees of the same variety that were never treated with BM were applied to the selected tree at usual times. After harvesting, some of the samples were processed to obtain ripe fresh, sun-dried and sulfited-dried products, according to the method reported by Asma [12][13][14][15][16][17][18]19]. They were carefully selected to ensure that the fruits were free of defects.…”

“…After its frequent application, copper may accumulate in the upper layers of soils and on the apricot trees, especially when the application times increase [17,18] Therefore, Cu determination in apricot samples is crucial and very important for better food safety and quality as well as human health.…”

“…Many different apricot varieties have been investigated by many researchers in the world and different phytochemical contents have been determined for each apricot variety [17][18][19][20][21][22][23][24][25][26].…”