Plant pathology is required for global food security, ecosystem health, and sustainable agriculture, yet opportunities to study plant pathology are limited. Plant pathology is also an excellent and accessible science for teaching biology, but it is underused in classes such as ecology and microbiology. Describing core concepts required for literacy in plant pathology will aid in advocating for and teaching plant pathology on campuses that currently lack courses in this discipline. Here, we propose a framework for defining undergraduate-level literacy in plant pathology by identifying 12 core concepts derived from analysis of upper-level course syllabi across universities. These core concepts span biological, ecological, social, and humanistic dimensions of plant disease. We also assessed established frameworks such as the American Association for the Advancement of Science (AAAS) Vision and Change report and American Society for Microbiology (ASM) curriculum guidelines to help build a call for action to further develop plant pathology curricula and to integrate interdisciplinary and humanistic perspectives into STEM education. In addition, we outlined competencies in plant pathology to illustrate how students could translate concepts into practice across diverse career pathways, including diagnostics, research, consulting, and regulatory roles. This framework is intended to serve as a call to action to further develop instructional resources for teaching plant pathology, to expand access to education in plant pathology, and to further support workforce training through courses, modules, and microcredentials built upon a shared understanding of plant pathology.
Riparian forest ecosystems face multiple anthropogenic pressures, including chronic nitrogen (N) pollution and invasive pathogens. However, the putative synergies among them are poorly understood. In the case of the keystone N-fixing tree Alnus glutinosa attacked by the exotic pathogen Phytophthora × alni , such pressures may act synergistically. N can indirectly promote susceptibility to the pathogen by affecting native soil microbiome composition and disrupting alder’s symbiotic partnership with actinobacteria of the genus Frankia . In a greenhouse experiment that involved the manipulation of N through fertilization and Frankia nodulation through soil sterilization, we examined the interactive effects of nodulation, soil microbiota, and P. × alni infection on alder performance. We found that alder survival after infection was strongly influenced by the origin of the substrate in which the plants were grown. Under N-fertilization, mortality due to Phytophthora was higher in plants grown without alder soil amendments. In contrast, in soils amended with alder soil, N-fertilization did not increase alder susceptibility to the pathogen, although it significantly reduced Frankia nodulation. Nodulation was lowest in plants carrying the highest pathogen loads, showing that P. × alni infection not only kills alders but also undermines N-fixation. Our findings show that N-fertilization and P. × alni suppress nodulation and therefore can simultaneously contribute negatively to the N-fixing central function of alders in river ecosystems. Our results also seem to discard any protective role of soil microbiome or Frankia nodulation against P. × alni on alder.
Kiwifruit (Actinidia deliciosa) is a crop of high economic importance, with Italy ranking as the third-largest global producer. In recent years, Italian kiwifruit orchards have been severely affected by kiwifruit vine decline syndrome (KVDS), a disease characterized by root rot, leaf chlorosis, phylloptosis, and progressive vine decline. To investigate the potential involvement of soilborne oomycetes in KVDS, a survey of symptomatic plants was conducted in Latina Province (Lazio, Italy). Two oomycete species, Pythium dissotocum and Globisporangium sylvaticum, were consistently isolated from diseased roots. Pathogenicity tests on A. deliciosa cultivar Hayward revealed that both species induced severe symptoms under waterlogged conditions, whereas only mild or no symptoms developed under regular irrigation. These results provide the first evidence that P. dissotocum and G. sylvaticum can contribute to KVDS symptomatology in Italy. These findings offer new insight into KVDS dynamics, highlighting the variability of pathogenic species involved. Similar oomycetes with comparable pathogenic traits have been previously reported, reinforcing the multifactorial nature of the disease and the influence of environmental stress, particularly waterlogging, on its expression.
Peacock eye disease, caused by the hemibiotrophic fungus Venturia oleaginea, is the most destructive and widespread disease of olive in Israel. In a national project to develop an environmentally friendly peacock eye disease-management protocol for the local olive industry, it was found that one or a few fungicide applications in the autumn effectively suppressed disease development in the concurrent season. Since fungicide application timing should be based on environmental criteria rather than a predefined seasonal schedule, the goal of the current study was to define criteria for predicting the occurrence of infection events. It was observed that peacock eye severity and leaf abscission were significantly lower in tree canopies facing sunrise between October and December, the presumed period of autumn infection events, than in those facing other directions. Accordingly, we used the uneven distribution of the disease with varying canopy orientation as a tool to ascertain the relative importance of the respective weather variables to infection. Duration of leaf wetness caused by dew was the most salient ambient condition showing consistent, albeit short-duration (≤2 h) differences between canopy sides. In vitro experiments were conducted to examine how this small difference leads to marked differences in disease severity and to define conditions promoting conidial germination, germ tube elongation, and sporulation. Based on these and our previous results, we defined criteria for predicting the occurrence of infection events in highly susceptible olive cultivars: a rain event of 15 mm or more (for 1 day or accumulated over several consecutive days), wetness duration of at least 6 h, and temperatures between 12 and 18°C during the wetting period. These criteria could serve to time fungicide applications.
