Alternaria porri en cebolla pdf free

Alternaria species are known as major plant pathogens. Alternaria solani is a fungal pathogen that produces a disease in tomato and potato plants called early blight. Natal submitted in fulfilment of the academic requirements for the degree of doctor of philosophy in the department of microbiology and plant pathology university of natal pieteraritzburg 1993. Alternaria porri altepodocuments eppo global database. Dec 01, 2016 purple blotch, caused by alternaria porri ellis cifferi is the most destructive foliar disease, prevalent in all allium growing countries of the world kareem et al. It is responsible for causing severe yield losses ranging from 2. Alternaria porri altepooverview eppo global database. Purple blotch is caused by the fungus alternaria porri. Because many of the members of this group have similar morphology, alternaria dauci has also been classified as formae specialis of carrots, or a. Purple blotch of onion angela madeiras, umass extension diagnostic lab purple blotch is caused by the fungus alternaria porri. It can infect all aboveground parts of the plant in addition to the bulb. Physiological plant pathology 1976 8, 8390 induction of sporulation of alternaria porri f. Initial symptoms appear on older leaves, usually late in the summer as spores are blown from infested debris.

In pre liminary experiments onion plants free from purple blotch symptoms were. The pathogen produces distinctive bullseye patterned leaf spots and can also cause stem lesions and fruit rot on tomato and tuber blight on potato. It is an important disease in warm, humid oniongrowing regions around the world. Alternaria porri conidia deposited on onion leaves formed one to several germination. Older leaves and plants are more susceptible to infection. They are also common allergens in humans, growing indoors and causing hay fever or hypersensitivity reactions that sometimes lead to asthma. Pdf morphology of infection of onion leaves by alternaria porri. The highest spore production ofstemphylium botryosum f. All fungi fungi and lichens of great britain and ireland.

Sporulation of both pathogens was inhibited by illumination during the entire wetting period or during the last 12 h of it. Alternaria dauci is included in the porri species group of alternaria, which is classified for having large conidium and a long, slender filiform beak. Rotem division of plant pathology, the volcani center, bet dagan, israel accepted for publication november 1975 only induction by sun or ultraviolet light induced sporulation of alternaria porri f. Except where otherwise noted, content on this site is licensed under a creative commons attribution, noncommercial cc bync licence. Continuing to use this website means you agree to our use of cookies. Garlic and leeks may be affected as well as onions. Largespored alternaria pathogens in section porri disentangled. Mancha purpura alternaria porri na cultura da cebola. The omnipresent fungal genus alternaria was recently divided into 24 sections based on molecular and morphological data. Morphology of infection of onion leaves by alternaria porri article pdf available in canadian journal of botany 728. Documents about alternaria porri altepo this website uses cookies our website uses cookies to ensure that we give you the best possible online experience. Effect of light on sporulation of alternaria porri f. We do not use these to store personal information about you. Porri is the largest section, containing almost all alternaria species with medium to large conidia and long beaks, some of which are important plant pathogens e.