| Monilinia fructicola | |
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| Symptoms of brown rot on cherries | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Leotiomycetes |
| Order: | Helotiales |
| Family: | Sclerotiniaceae |
| Genus: | Monilinia |
| Species: | M. fructicola |
| Binomial name | |
| Monilinia fructicola | |
| Synonyms [1] | |
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Monilinia fructicola is a species of fungus in the order Helotiales. A plant pathogen, it is the causal agent of brown rot of stone fruits.
Stone fruits such as apricot and peaches originated in China and spread through old trade routes 3–4000 years ago. Nectarines are more recent (at least 2000 years). Cherries and European plums originated in Europe, although the Japanese plum originated in China. [2]
Trees exposed to cold in autumn and early spring can develop cankers under the bark of the trunk or branches. Cankers are usually associated with the production of amber-coloured gum that contains bacteria and oozes on to the outer bark. Unfortunately, there are few control methods for fungal spores apart from copper sprays. [2]
Brown rot causes blossom blight, twig blight; twig canker and fruit rot. [3] Brown rot is caused by a fungus that produces spores, and can be a major problem during particularly wet seasons. Prolonged wet weather during bloom may result in extensive blossom infection. The length of wet periods required for blossom infection depends upon the temperature. Humid wet conditions are when the fruit trees are most at risk from infection. Young green fruit can be infected just before autumn, but the infection often remains inactive until near maturity of the fruit. Brown rot can spread after harvest. Mature fruit can decay in only 2 days under warm conditions. [3]
Blossom Blight: Infected blossoms wilt, shrivel and become covered with greyish mould. Petals may appear light brown or water-soaked. Blighted blossoms do not produce fruit. Dead blossoms may stick to spurs and twigs until harvest, providing a source of spores for the fruit rot phase. [3]
Twig Blight and Canker: On peaches and apricots the infection may spread to twigs, causing brownish, oval cankers that may girdle and kill twigs. [3]
Fruit rot appears as small, circular brown spots that increase rapidly in size causing the entire fruit to rot. Greyish spores appear in tufts on rotted areas. [4] Infected fruit eventually turn into shrivelled, black mummies that may drop or remain attached to the tree through the winter. Brown rot can be serious on injured fruit such as cherries split by rain. [3]
Overwintering: The fungus over-winters in mummified fruit on the ground or in the tree and in twig cankers. Spring Infection: two types of spores are produced in spring which can infect blossoms. Conidia are produced on cankers and fruit mummies on the tree. Apothecia (small mushroom-like structures) form on mummies lying on the ground. [3] The apothecia discharge ascospores during the bloom period, but don't contribute to fruit infection later in season. [3] Secondary Infection: Spores produced on blighted blossoms provide a source of infection for ripening fruit. Infected fruit become covered with greyish spores which spread by wind and rain to healthy fruit. Insects may also contribute to the spread of brown rot spores. [3]
A plant's first line of defence against infection is the physical barrier of the plant's “skin”, the epidermis of the primary plant body and the periderm of the secondary plant body. This first defence system, however, is not impenetrable. Viruses, bacteria, and the spores and hyphae of fungi can still enter the plant through injuries or through the natural openings in the epidermis, such as stomata. Once a pathogen invades, the plant mounts a chemical attack as a second line of defence that destroys the pathogens and prevents their spread from the site of infection. This second defence system is enhanced by the plant's inherited ability to recognise certain pathogens. [5]
Elicitors: Oligosaccharins, derived from cellulose fragments released by cell wall damage, are one of the major classes of elicitors. Elicitors stimulate the production of antimicrobial compounds called phytoalexins. Infections also activate genes that produce PR proteins (pathogenesis-related proteins). Some of these proteins are antimicrobial, attacking molecules in the cell wall of a bacterium. Others may function as signals that spread “news” of the infection to nearby cells. Infection also stimulates the cross-linking of molecules in the cell wall and the deposition of lignin, responses that set up a local barricade that slows spread of the pathogen to other parts of the plant. [5]
Orchard sanitation, removing fruit mummies and pruning any cankered or dead twigs will reduce inoculum levels, which will improve the effectiveness of fungicide sprays. [3]
Primarily treatment is chemical; using fungicidal sprays to control the spread of the fungus. Spraying occurs during all phases, blossoms, green fruit, and mature fruit. Stone fruit trees' only natural defences are “skin” and chemical reactions to being attacked by the fungi, but this is a limited defence, so spraying and orchard sanitation are the best way to control spread of the fungus. [3]
Fire blight, also written fireblight, is a contagious disease affecting apples, pears, and some other members of the family Rosaceae. It is a serious concern to apple and pear producers. Under optimal conditions, it can destroy an entire orchard in a single growing season.
Peach leaf curl is a plant disease characterized by distortion and coloration of leaves and is caused by the fungus Taphrina deformans, which infects peach, nectarine, and almond trees. T. deformans is found in the United States, Europe, Asia, Africa, Australia, and New Zealand. Peach leaf curl reduces the amount of leaves and fruit produced by peach and nectarine trees.
Grape black rot is a fungal disease caused by an ascomycetous fungus, Guignardia bidwellii, that attacks grape vines during hot and humid weather. “Grape black rot originated in eastern North America, but now occurs in portions of Europe, South America, and Asia. It can cause complete crop loss in warm, humid climates, but is virtually unknown in regions with arid summers.” The name comes from the black fringe that borders growing brown patches on the leaves. The disease also attacks other parts of the plant, “all green parts of the vine: the shoots, leaf and fruit stems, tendrils, and fruit. The most damaging effect is to the fruit”.
Diplodia tip blight, also known as Sphaeropsis blight, is a widespread disease affecting conifers caused by an opportunistic fungal pathogen, Diplodia sapinea. It is found in “both hemispheres between the latitudes 30° and 50° north and south". The diseases symptoms include: damping off and collar rot of seedlings, stem canker, root disease, and, most commonly, shoot blight. These symptoms have caused significant economic loss to nurseries and pine plantations. In a nursery in the north-central United States, losses of 35% have been reported. Shoot blight and eventual die back can cause a reduction of marketable volume in timber by 63%. Infection of terminal shoots can result in dead-top which significantly limits the usable length of the tree trunk. The presence of the pathogen in concert with severe weather conditions can lead to extreme loss. Following a severe hailstorm in South Africa, nearly 5,000 acres of pine plantation were infected with Diplodia tip blight. It was necessary to prematurely harvest large swaths of the plantations resulting in a loss of 45%. Areas that were not harvested prematurely still suffered an average timber loss of 11%.
Alternaria alternata is a fungus causing leaf spots, rots, and blights on many plant parts, and other diseases. It is an opportunistic pathogen on over 380 host species of plant.
Botryosphaeria obtusa is a plant pathogen that causes frogeye leaf spot, black rot and cankers on many plant species. On the leaf it is referred to as frogeye leaf spot; this phase typically affects tree and shrubs. In fruit such as the apple, cranberry and quince, it is referred to as black rot, and in twigs and trunks it causes cankers.
Leptosphaeria coniothyrium is a plant pathogen. It can be found around the world.
Nectria cinnabarina, also known as coral spot, is a plant pathogen that causes cankers on broadleaf trees. This disease is polycyclic and infects trees in the cool temperate regions of the Northern Hemisphere. N. cinnabarina is typically saprophytic, but will act as a weak parasite if presented with an opportunity via wounds in the tree or other stressors that weaken the tree's defense to the disease. A study published in 2011 showed that this complex consists of at least 4 distinct species. There are only a few ways to manage this disease with techniques such as sanitation and pruning away branches that have the cankers. N. cinnabarina is not as significant a problem as other Nectria spp., some of which are the most important pathogens to infect hardwood trees.
Monilinia laxa is a plant pathogen that is the causal agent of brown rot of stone fruits.
Alternaria solani is a fungal pathogen that produces a disease in tomato and potato plants called early blight. The pathogen produces distinctive "bullseye" patterned leaf spots and can also cause stem lesions and fruit rot on tomato and tuber blight on potato. Despite the name "early," foliar symptoms usually occur on older leaves. If uncontrolled, early blight can cause significant yield reductions. Primary methods of controlling this disease include preventing long periods of wetness on leaf surfaces and applying fungicides. Early blight can also be caused by Alternaria tomatophila, which is more virulent on stems and leaves of tomato plants than Alternaria solani.
Phytophthora megakarya is an oomycete plant pathogen that causes black pod disease in cocoa trees in west and central Africa. This pathogen can cause detrimental loss of yield in the economically important cocoa industry, worth approximately $70 billion annually. It can damage any part of the tree, causing total yield losses which can easily reach 20-25%. A mixture of chemical and cultural controls, as well as choosing resistant plant varieties, are often necessary to control this pathogen.
Monilinia fructigena is a plant pathogen in the fungus kingdom causing a fruit rot of apples, pears, plums, peaches and cherries.
Septoria lycopersici is a fungal pathogen that is most commonly found infecting tomatoes. It causes one of the most destructive diseases of tomatoes and attacks tomatoes during any stage of development.
This article summarizes different crops, what common fungal problems they have, and how fungicide should be used in order to mitigate damage and crop loss. This page also covers how specific fungal infections affect crops present in the United States.
Monilinia oxycocci (Woronin) Honey,, common names cranberry cottonball, cranberry hard rot, tip blight, is a fungal infection of large cranberry and small cranberry. The tips of young flowering shoots wilt before they flower. Fruit that forms on the plant can then be infected by the asexual spores traveling through the plant, causing the berries to harden, turn cottony on the inside, and dry out instead of maturing. The berries are filled with a cotton-like fungus and are generally yellowish with tan stripes or blotches at maturity, making them unmarketable. It results in important economic impacts on many cranberry marshes, particularly in Wisconsin.
Septoria musiva, correct taxonomic name: Sphaerulina musiva, is an ascomycete fungus responsible of a leaf spot and canker disease on poplar trees. It is native on the eastern cottonwood poplar Populus deltoides, causing only a leaf spot symptom. On susceptible hybrid poplars, S. musiva causes necrotic lesions on the leaves which lead to premature defoliation, and cankers on the stem and branches which can reduce growth, predispose the tree to colonisation by secondary organisms, and cause stem breakage.
Phomopsisblight of juniper is a foliar disease discovered in 1917 caused by the fungal pathogen Phomopsis juniperovora. The fungus infects new growth of juniper trees or shrubs, i.e. the seedlings or young shoots of mature trees. Infection begins with the germination of asexual conidia, borne from pycnidia, on susceptible tissue, the mycelia gradually move inwards down the branch, and into the main stem. Management strategies mainly include removing and destroying diseased tissue and limiting the presence of moisture on plants. Junipers become resistant to infection as they mature and the young yellow shoots turn dark green. Preventive strategies include planting only resistant varieties and spraying new growth with fungicide until plants have matured.
Gummy stem blight is a cucurbit-rot disease caused by the fungal plant pathogen Didymella bryoniae. Gummy stem blight can affect a host at any stage of growth in its development and affects all parts of the host including leaves, stems and fruits. Symptoms generally consist of circular dark tan lesions that blight the leaf, water soaked leaves, stem cankers, and gummy brown ooze that exudes from cankers, giving it the name gummy stem blight. Gummy stem blight reduces yields of edible cucurbits by devastating the vines and leaves and rotting the fruits. There are various methods to control gummy stem blight, including use of treated seed, crop rotation, using preventative fungicides, eradication of diseased material, and deep plowing previous debris.
Shot hole disease is a serious fungal disease that creates BB-sized holes in leaves, rough areas on fruit, and concentric lesions on branches. The pathogen that causes shot hole disease is Wilsonomyces carpophilus.
Xanthomonas campestris pv. juglandis is an anaerobic, Gram negative, rod-shaped bacteria that can affect walnut trees though the flowers, buds, shoots, branches, trunk, and fruit. It can have devastating effects including premature fruit drop and lesions on the plant. This pathogen was first isolated by Newton B. Pierce in California in 1896 and was then named Pseudomonas juglandis. In 1905 it was reclassified as Bacterium juglandis, in 1930 it became Phytomas juglandis, and in 1939 it was named Xanthomas juglandis. The International Standards for Naming Pathovars declared it to be named Xanthomonas campestris pv. juglandis in 1980. There have been recent proposals to change the name once again to Xanthomonas arboricola pv. juglandis, but this has not yet been universally accepted.
| Authority control databases: National |
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