• pathogens
  • Recent studies have revealed requirement for autophagy in diverse functions such as nutrient homeostasis, organelle degradation and programmed cell death in filamentous fungal pathogens, for proper morphogenesis and differentiation during critical steps of infection. (mdpi.com)
  • Penetration and establishment of infection in host tissue are key events in the disease cycles of fungal pathogens. (apsnet.org)
  • Beta spores are rarely found in the wild, but proliferate when P. juniperova is grown on cultures of potato dextrose agar.If the resources for this method of diagnosis are not available, contact a local extension office to be directed to an expert in plant pathogens or a laboratory that can assist with the process. (wikipedia.org)
  • 1996). For instance, conifer oleoresin, a complex mixture of terpenoids secreted in response to attack by insect predators, is toxic to insects and their symbiotic fungal pathogens (Philips and Croteau, 1999). (redorbit.com)
  • All three of these diseases caused by P. irregulare can be caused by other pathogens as well, so a disease diagnosis is not necessarily indicative of P. irregulare In order to identify Pythium irregulare it is necessary to isolate the organism and observe it microscopically. (wikipedia.org)
  • temperature
  • Excessively deep planting, wet or dry soil conditions, and low temperature are all conducive to the development of the disease. (ufl.edu)
  • For example, they can plant the seed when the soil temperature is higher than what is ideal for teliospore germination, e.g., above 68 °F. For winter wheat this means planting in early fall and for spring wheat planting in late spring. (wikipedia.org)
  • These thick walled overwintering structures can withstand large temperature fluctuations within the soil and even resist desiccation. (wikipedia.org)
  • Recent studies have confirmed and concluded that rainfall and temperature are the key factors in the release of spores and that the duration of the rainfall or wet period is not a factor. (apsnet.org)
  • Research on temperature requirements for germination and spore production is currently being conducted. (wikipedia.org)
  • During the epizootic phase of most fields (late May to late June), daily mean RH ranged from 70% to 79% and daily mean temperature ranged between 21.1°C and 24.3°C. Disease progression within CGM populations was documented in two of the nine fields. (scielo.br)
  • fungi
  • Figure 1 provides a diagrammatic representation of important structures formed during the infection process of many fungi. (apsnet.org)
  • citation needed] Conidia are often the method by which some normally harmless but heat-tolerating (thermotolerant), common fungi establish infection in certain types of severely immunocompromised patients (usually acute leukemia patients on induction chemotherapy, AIDS patients with superimposed B-cell lymphoma, bone marrow transplantation patients, or major organ transplant patients suffering from graft versus host disease). (wikipedia.org)
  • Optimum conditions for spore germination are soil temperatures in the range of 5-15 °C (41-59 °F). Bunt fungi overwinter as dikaryotic teliospores typically on seed and occasionally in soil. (wikipedia.org)
  • Temperatures above 90° F kill some Powdery mildew fungi and spores and the presence of free water can reduce spore germination. (umass.edu)
  • When roots of a host crop come near the resting structure (about 2mm), root exudate promotes germination and the fungi grows out of the structure and toward the plant. (wikipedia.org)
  • In plant pathogenic fungi, germination is frequently stimulated by plant-specific signals, such as plant-derived compounds or the physicochemical properties of the plant surface. (beds.ac.uk)
  • soil-borne
  • Since pineapple disease is a soil-borne disease, crop rotation or a fallow period between cane crops may prove to be of some benefit in reducing its impact. (ufl.edu)
  • It was believed that overwintering soil-borne inoculum wasn't important in the disease cycle, but recent studies suggest H.solani may survive in the soil for a short period of time, which can cause more infection. (wikipedia.org)
  • Crop Rotation: In order to reduce the risk of infection of pea crops from infected residue and soil-borne survival structures in a field, pea crops should be grown only every three to four years in the same field. (wikipedia.org)
  • inoculum
  • There, the spores may survive for several years, serving as a source of inoculum for the next crop. (ufl.edu)
  • It is mainly a seed borne disease and the primary source of inoculum is mainly infected potato seed tubers. (wikipedia.org)
  • Mummified berries and twig bark are considered to be primary sources of inoculum for the disease. (wikipedia.org)
  • This characteristic is a reason why coffee crowns are important sources of inoculum in Coffee Berry Disease (CBD). (wikipedia.org)
  • Spores are laterally dispersed between trees and branches by wind and rain, yet localized, downward movement is the prototypical inoculum movement. (wikipedia.org)
  • powdery
  • When the mature kernels are broken, they are full of a black, powdery mass of the fungal spores. (wikipedia.org)
  • Powdery mildew is a polycylic disease that thrives in warm, moist environments. (wikipedia.org)
  • When the disease begins to develop, it looks like a white powdery substance. (wikipedia.org)
  • The disease is easily recognizable as a white to gray powdery growth on leaves and sometimes stems and flowers. (umass.edu)
  • Once powdery mildew gets established, it does not need water or rain for infection - in fact, heavy rain is detrimental because it washes the spores from the leaves and causes them to burst. (westernfarmpress.com)
  • In the spring, the grape powdery mildew fungus ( Erysiphe necator ) releases ascospores from cleistothecia (overwintering structures) that are lodged in cracks in the grapevine bark. (westernfarmpress.com)
  • reddish brown
  • The spores are reddish brown, round and subovoid and may be smooth to moderately echinulate. (wikipedia.org)
  • These spores are reddish brown, smoothly rounded, and they tend to be in clumps of 5-6 with sterile cells around them. (wikipedia.org)
  • viable
  • The Ascochyta pisi spores are viable on crop debris, although they do not survive for more than a year. (wikipedia.org)
  • In recent years, pre plant soil fumigation with chloropicrin in non-tarped, raised beds has proven to be economically viable and beneficial for reducing wilt disease and increasing yield and quality of potato in North America. (wikipedia.org)
  • temperatures
  • In Florida, germination is most rapid early in the season (September-December) when soil temperatures are warmest. (ufl.edu)
  • These small black globular structures are resistant to adverse temperatures and can remain dormant in the soil for years even without a host. (wikipedia.org)
  • Prevalence of the disease decreases from higher temperatures and lower moisture in the summer. (wikipedia.org)
  • The ideal conditions for the spread of this disease are high temperatures and high humidity. (wikipedia.org)
  • Typically, smut poses more of a problem in winter wheat than in spring wheat because in autumn, when winter wheat is planted, there is a longer period of more favorable temperatures for teliospore germination than compared to the planting season for spring wheat. (wikipedia.org)
  • High humidity, relatively warm temperatures, and high altitude are ideal for disease formation. (wikipedia.org)
  • Most infection begins when spring rain (2.5mm) falls and temperatures are approximately 15°C or higher. (wikipedia.org)
  • When the conk temperatures are above freezing the spores of the fungus are released and carried by wind currents to land in open wounds or stumps of cut trees. (wikipedia.org)
  • Temperatures above 95 degrees Fahrenheit inhibit spore germination, and the fungus may be killed at temperatures above 104 degrees Fahrenheit. (westernfarmpress.com)
  • plant
  • Pineapple disease can result in young plant-cane crops having a patchy, uneven appearance (Figure 2). (ufl.edu)
  • Fungal spores on plant surfaces usually can survive in a dormant state during periods of unfavorable environmental conditions. (apsnet.org)
  • In addition to facing risks from unfavorable environmental conditions, germinating spores must breach the physical barriers provided by the host (cuticle, cell walls) and face the onslaught of plant biochemical defense mechanisms present in host cytoplasm. (apsnet.org)
  • The disease attacks at all stages of growth, which leaves the plant to turn yellow and wilt when fully developed because the roots are rotting. (wikipedia.org)
  • Silver scurf is a plant disease of potato, which is caused by the anamorphic ascomycete fungus, Helminthosporium Solani. (wikipedia.org)
  • Like with many other fungal plant diseases, a diagnosis can be made by looking for the specific sexual structures of the fungus and observing them for the specific characteristics of silver scurf. (wikipedia.org)
  • In some cases, specialized macroscopic fruiting structures perhaps 1mm or so in diameter containing masses of conidia are formed under the skin of the host plant and then erupt through the surface and allow the spores to be distributed by wind and rain. (wikipedia.org)
  • Acervular conidiomata, or acervuli, are cushion-like structures that form within the tissues of a host organism: subcuticular, lying under the outer layer of the plant (the cuticle), intraepidermal, inside the outer cell layer (the epidermis), subepidermal, under the epidermis, or deeper inside the host. (wikipedia.org)
  • It is important to plant pea crops as far from the previous years' field as possible in order to limit the spread of infection. (wikipedia.org)
  • It is advised to plant seed with less than 10% ascochyta infection if that quality of seed can be sourced. (wikipedia.org)
  • Plant Disease 96:909. (uoguelph.ca)
  • Plant Disease 95:1190. (uoguelph.ca)
  • Under intensive plant maintenance systems, these natural mechanisms may be insufficient to guard against disease outbreaks without significant economic loss. (uoguelph.ca)
  • Blue Fungal spore masses are produced on the roots of the plant where macroconidia are formed. (wikipedia.org)
  • Other control measures include: use wide spacing when planting to reduce the need for thinning and reduce the potential root grafts, thin only when spores are less abundant, (January through March), and plant tree species that are less susceptible. (wikipedia.org)
  • Infection does not spread to species of plants in other plant families. (umass.edu)
  • Additional strategies to manage the disease include crop rotation, the use of resistant varieties and deep plowing (to accelerate the decomposition of infected plant residue). (wikipedia.org)
  • Some times only one side of the plant will appear infected because once in the vascular tissues, the disease migrates mostly upward and not as much radially in the stem. (wikipedia.org)
  • In older plants, the infection can cause death, but often, especially with trees, the plant will be able to recover, or at least continue living with the infection. (wikipedia.org)
  • Once the plant dies, more sporangium can form, release zoospores, and repeat the infection cycle. (wikipedia.org)
  • interaction as a new model pathosystem for biotrophic fungal plant infections of the head smut type (Rabe et al. (readbyqxmd.com)
  • Understanding of plant-fungal interaction is constantly coevolving along with the evolution of both the interacting partners. (springer.com)
  • This study also sheds light on the impact of plant-fungal association on tritrophic interactions with other beneficial and pathogenic biotic components. (springer.com)
  • Balestrini R, Lanfranco L (2006) Fungal and plant gene expression in arbuscular mycorrhizal symbiosis. (springer.com)
  • infects
  • Monilinia laxa is an ascomycete fungus that is responsible for the brown rot blossom blight disease that infects many different types of stone fruit trees, such as apricots, cherries and peaches. (wikipedia.org)
  • pathogenic
  • Many fungal species differentiate specialized infection structures called appressoria on the host surface, which are essential for successful pathogenic development. (beds.ac.uk)
  • Our results show that the control of basic cellular processes such as those coupling cell cycle and morphogenesis during fungal infection can be substantially different between fungal species with similar lifestyles and pathogenic strategies. (beds.ac.uk)
  • species
  • Where the disease has occurred, recropping with further Allium species should be avoided for many years. (wikipedia.org)
  • More than one fungal species can cause this disease. (wikipedia.org)
  • Due to the ecology, disease type, host range/preference, interfertility group, and genetic information, H. irregulare (formerly known as Heterobasidion annosum P ISG) was designated a new species and distinguished from Heterobasidion occidentale (formerly known as Heterobasidion annosum S ISG). (wikipedia.org)
  • Certain species of roses and cultivars of old garden roses are considered more resistant to the disease than modern cultivars. (ufl.edu)
  • Verticillium wilt is a wilt disease of over 350 species of eudicot plants caused by six species of Verticillium genus, V. dahliae, V. albo-atrum, V. longisporum, V. nubilum, V. theobromae and V. tricorpus. (wikipedia.org)
  • Many eudicot species and cultivars are resistant to the disease and all monocots, gymnosperms and ferns are immune. (wikipedia.org)
  • It is also important to note that many diagnosticians do not identify to the species level because it can be difficult to find all necessary microscopic structures and many management techniques can be applied to all Pythium species. (wikipedia.org)
  • infections
  • Epidemics that seem to develop overnight are often the result of undetected low level infections that have spread spores throughout the greenhouse. (umass.edu)
  • increase susceptibility
  • Long hot-water treatments used to control other diseases may have a detrimental effect on germination and thus may actually increase susceptibility to pineapple disease. (ufl.edu)
  • Currently, no known host factors have been identified that have been linked to increase susceptibility or development of the disease. (wikipedia.org)
  • lesions
  • The viability of the conidia obtained from the volatile-treated and non-treated disease lesions was tested with the vital stains fluorescein diacetate (FDA) and propidium iodide (PI). (uoguelph.ca)
  • Under humid conditions, the fruiting structures on the lesions may produce pink spore masses that become white with age. (wikipedia.org)
  • In older lesions, black spore-bearing structures, called acervuli, can be observed as well as white, slimy masses of conidia (Fig. 2a). (ufl.edu)
  • perithecia
  • Additionally, ascospores produced by a sexual stage are produced within small, dark-brown to black, vase-like structures called perithecia. (ufl.edu)
  • conditions
  • If possible, planting should take place when conditions favor rapid germination. (ufl.edu)
  • Environmental conditions influence the germination with it favoring cooler weather (50-70 F). If there is high soil moisture present, germination and infection will be favored. (wikipedia.org)
  • It seems as though the environmental conditions are what plays a major role in severity of the disease. (wikipedia.org)
  • In addition to this, there are many cultural practices which affect the conditions that favor disease spread and development. (wikipedia.org)
  • The release of these spores begins in spring and can continue into the summer if moist conditions persist. (wikipedia.org)
  • Agronomic practices promoting varieties and conditions that limit lodging and avoiding fields with excess nitrogen can reduce the spread and intensity of disease. (wikipedia.org)
  • Teliospores come to rest in soils, and when conditions are right, they give rise to more basidiospores, further spreading the infection. (wikipedia.org)
  • The spores are covered in a gelatinous coat which expands under wet conditions to facilitate in spore dispersal during rain. (wikipedia.org)
  • Cooler conditions, such as shading and poor aeration, promote infection due to a higher relative humidity, optimally 85% or greater. (wikipedia.org)
  • P. megakarya depends heavily on the correct environmental conditions to cause disease. (wikipedia.org)
  • Pythium irregulare requires very specific environmental conditions to produce disease, so control of environment is the first step. (wikipedia.org)
  • Under optimal conditions, the disease can spread rapidly, as the time from infection to production of conidia can be as short as seven days. (westernfarmpress.com)
  • development in hydroxyurea-treated spores continued only for a limited number of cell divisions, but normal numbers of fully developed mature appressoria were formed under conditions that support appressoria formation. (beds.ac.uk)
  • resistant
  • Generally, strategies to prevent flag smut include use of disease resistant cultivars, chemical seed treatments, and crop rotation to reduce amount of inocula present. (wikipedia.org)
  • India and the United States currently have low incidence of this disease due to deployment of resistant cultivars. (wikipedia.org)
  • Despite the economic impact and numerous studies on this disease, little is known about the cytological features during infection by M. pinodes , especially in resistant interactions. (frontiersin.org)
  • Junipers become resistant to infection as they mature and the young yellow shoots turn dark green. (wikipedia.org)
  • For instance, sesquiterpenoid phytoalexins, including 2,7-dihydroxycadalene, 2- hydroxy-7-methoxycadalene, lacinilene C, and lacinilene C 7-methyl ether, significantly accumulate in the leaves of resistant cotton (Gossypium hirsutum) lines but not in susceptible varieties after infection by Xanthomonas campestris pv malvacearum (Essenberg et al. (redorbit.com)
  • In addition, a cold snap can also make grapevines more resistant to infection. (westernfarmpress.com)
  • Berries became substantially resistant to infection by three to four weeks after bloom, resulting in diffuse, non-sporulating colonies on berries, and were virtually immune at six to eight weeks after bloom. (westernfarmpress.com)
  • diseases
  • In people with predisposing lung diseases-such as persistent asthma or cystic fibrosis (or rarer diseases such as chronic granulomatous disease or Hyper-IgE syndrome)-several factors lead to an increased risk of ABPA. (wikipedia.org)
  • spherical
  • Cleistothecia, which are the overwintering structures, present themselves as tiny, spherical fruiting structures that go from white, to yellowish-brown to black in color, and are about the size of the head of a pin. (wikipedia.org)
  • ascospores
  • In addition, apothecia, which are small, open cup, mushroom-like sexual propagative structures of M. laxa that produce ascospores, also develop on the fallen fruits on the ground. (wikipedia.org)