How Does Botrytis cinerea Infect Red Raspberry?

Abstract

Botrytis cinerea, causal agent of gray mold, is one of the most important pathogens affecting raspberry in the U.S. Pacific Northwest and worldwide. Fungicides are currently applied to control the disease starting from 5 to 10% bloom and continuing on a calendar basis throughout the season rather than according to inoculum level or infection risk primarily because the disease cycle on red raspberry is poorly understood. Botrytis cinerea was isolated from raspberry flowers and fruit sampled at seven developmental stages during each of 2015 and 2016 in a northwestern Washington raspberry field untreated with fungicides. Incidence of colonization of flowers was low (15% of total sampled flowers), but increased as fruit developed, and peaked in mature fruit (67% of total sampled fruit). In the early stages of flower development, B. cinerea recovery was greatest from the carpel (80% of carpels colonized) compared with other floral organs. As fruit matured, additional floral parts were colonized by B. cinerea, possibly facilitating secondary internal or external infections of mature fruit. Average weekly minimum air temperature, average weekly night air temperature, cumulative rain, average weekly leaf wetness percentage, and duration of leaf wetness >90% were significantly positively correlated with B. cinerea colonization of raspberry in NW Washington during two seasons of this study. Our data does not support the hypothesis that the bloom period is the critical window for B. cinerea colonization of red raspberry and suggest that later colonization of developing fruit may be more important for gray mold development on raspberry. The outcomes of this research provide useful information for improvement of gray mold disease management strategies for red raspberry in NW Washington and elsewhere.

Recent Advances in Hormonal Regulation and Cross-Talk during Non-Climacteric Fruit Development and Ripening

“…The fungus Botrytis cinerea Pers.:Fr. has often been reported as the main pathogen causing rapid fruit decay, especially in grape, strawberry, and raspberry [38][39][40]. Cell wall changes accompanied by an intense decrease in the content and the degree of methyl-esterification of pectin during ripening have been reported in different raspberry cultivars [41], Chilean strawberry [Fragaria chiloensis (L.) Mill.]…”

Redox Status, JA and ET Signaling Pathway Regulating Responses to Botrytis cinerea Infection Between the Resistant Cucumber Genotype and Its Susceptible Mutant

“…To increase the production and economic efficiency, most of the farmers grow their vegetables continuously in greenhouse that may cause continuous cropping obstacle and ultimately the accumulation of pathogens such as B. cinerea (Li et al, 2016). High humidity with 20-30°C temperature inside the greenhouse is suitable for the epidemic B. cinerea (Kozhar and Peever, 2018). This fungus can kill the host cells through the production of toxins and acquire nutrients from death cells, thus, a parasitic relationship starts with infection process.…”

Alternative Molecular-Based Diagnostic Methods of Plant Pathogenic Fungi Affecting Berry Crops—A Review

“…The pathogen can propagate on harvested strawberry, raspberry, blueberry and blackberry fruits at temperatures above freezing, which is a significant problem for the cold storage of soft fruits [40]. The disease may occur on fruits at any time from seedling to sale, what makes it difficult to predict and effectively counteract [38,41]. However, it is known that ripe fruits are most susceptible to infection [42].…”