Dual Specificity of Alternaria to Cause Plant Disease and Allergic Reactions
Nippon Journal of Environmental Science
Alternaria is a ubiquitous fungal genus which includes endophitic, saprophytic and pathogenic species. They can cause pre and post-harvest diseases in numerous crops and world-wide economic losses. Alternaria spp. with small conidia size, less than 60 μm, are categorized as small spore Alternaria. Alternaria alternata, Alternaria arborescens, and Alternaria tenuissima are among the most commonly reported small spore Alternaria spp. These species represent a disease complex on some hosts, often
... some hosts, often isolated from a single plant. Among the species, there remain overlapping morphological characteristics, and often it is not easy to differentiate the species microscopically. These pathogens usually appeared in anamorph, or asexual reproductive stage and the sexual reproduction is mostly known. There are very few studies on the genetic structure and evolutionary trajectory of the pathogen populations in the agroecosystems. The conidia are usually produced on leaf lesions, and often colonize in wounds. Asexual spores are larger than other anemophilous pollen and fungal spores, but they are found in high quantities in the air. The spores can disperse through air currents and rainfall. However, they are also known to be an allergenic fungus. A recent study in Europe has shown that Alternaria sp and its aerial asexual spores' inhalation of patients escalated the allergy by 8.9%. And it has also been pronounced as a risk factor for the development, persistence, and severity of asthma. Hence, it is necessary to identify the indoor and outdoor Alternaria species that are particularly involved in allergenic or asthma reactions.