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Tree Injection
Tree injection—also known as trunk injection or stem injection,—is a method of targeting a precise application of pesticides, plant resistance activators, or fertilizers into the xylem vascular tissue of a tree with the purpose of protecting the tree from pests, or to inject nutrients to correct for nutrient deficiencies. This method largely relies on harnessing the tree's vascular system to translocate and distribute the active compounds into the wood, canopy and roots where protection or nutrition is needed. Tree injection is currently the most popular method for control of damaging insects, pathogens, and nematodes in landscape tree care. Description Trunk injection has been developed primarily for use on large size trees and in proximity of urban areas where ground- and air-spray applications are impractical due to substantial drift-driven pesticide losses or not allowed due to potential human exposure. However, the prime driver of tree injection use has been a wide spre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytophthora Ramorum
''Phytophthora ramorum'' is the oomycete (a type of protist) plant pathogen known to cause the disease sudden oak death (SOD). The disease kills oak and other species of trees and has had devastating effects on the oak populations in California and Oregon, as well as being present in Europe. Symptoms include bleeding cankers on the tree's trunk and dieback of the foliage, in many cases leading to the death of the tree. ''P. ramorum'' also infects a great number of other plant species, significantly woody ornamentals such as ''Rhododendron'', ''Viburnum'', and '' Pieris'', causing foliar symptoms known as ramorum dieback or ramorum blight. Such plants can act as a source of inoculum for new infections, with the pathogen producing spores that can be transmitted by rainsplash and rainwater. ''P. ramorum'' was first reported in 1995, and the origins of the pathogen are still unclear, but most evidence suggests it was introduced as an exotic species to Europe and North America in se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmopara Viticola
''Plasmopara viticola'', the causal agent of grapevine downy mildew, is a heterothallic oomycete that overwinters as oospores in leaf litter and soil. In the spring, oospores germinate to produce macrosporangia, which under wet condition release zoospores. Zoospores are splashed by rain into the canopy, where they swim to and infect through stomata. After 7–10 days, yellow lesions appear on foliage. During favorable weather, the lesions sporulate and new secondary infections occur. Description ''Plasmopara viticola'', also known as grape downy mildew, is considered to be the most devastating disease of grapevines in climates with relatively warm and humid summers. It was first observed in 1834 by Schweinitz on ''Vitis aestivalis'' in the southeastern United States. Shortly after this first observation, the pathogen was introduced to European countries where it played a devastating role in the yield and production of their grapes, and consequently their wine. France was among th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Codling Moth
The codling moth (''Cydia pomonella'') is a member of the Lepidopteran family Tortricidae. They are major pests to agricultural crops, mainly fruits such as apples and pears. Because the larvae are not able to feed on leaves, they are highly dependent on fruits as a food source and thus have a significant impact on crops. The caterpillars bore into fruit and stop it from growing, which leads to premature ripening. Various means of control, including chemical, biological, and preventive, have been implemented. This moth has a widespread distribution, being found on six continents. Adaptive behavior such as diapause and multiple generations per breeding season have allowed this moth to persist even during years of bad climatic conditions. Geographic distribution Although the geographic origin of codling moths is unclear, there are theories of these moths originating from either Europe or the Mediterranean. Scholars believe that the codling moths were introduced to the Americas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Choristoneura Rosaceana
''Choristoneura rosaceana'', the oblique banded leaf roller or rosaceous leaf roller, is a moth of the family Tortricidae. It is native to North America, but has been accidentally introduced into other parts of the world. The wingspan is 7.5–11 mm for males and 11.5–14 mm for females. Adults are on wing from June to July and again from August to September in most of its range. Description The caterpillar is green with a black head. The adult is a small, light brown moth. Symptoms and signs The presence of the species is suggested by rolled, tied and chewed leaves and minor feeding damage on fruits. Damage can be extensive on rosaceous plants. Host plants Recorded host plants are: *'' Acer'' *''Aesculus'' *''Betula'' *''Cirsium'' *''Crataegus'' *''Corylus'' *''Cornus'' *''Cotoneaster'' *''Dianthus'' (carnation) *''Fragaria'' (strawberry) *''Fraxinus'' *''Lonicera'' *''Malus'' *''Picea'' *''Pinus'' *''Platanus'' *''Populus'' *''Prunus'' *''Pyracantha'' *''Quercu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venturia Inaequalis
''Venturia inaequalis'' is an ascomycota, ascomycete fungus that causes the apple scab disease. Systematics ''Venturia inaequalis'' anamorphs have been described under the names ''Fusicladium dendriticum'' and ''Spilocaea pomi''. Whether ''V. inaequalis'' is a single species or contains several cryptic species has been a matter of debate for a long time. Recent genetic studies have revealed a considerable uniformity of the species. In addition, the fungus ''Spilocaea pyracanthae'', a parasite of ''Pyracantha'' appeared not to genetically differ from ''V. inaequalis'', being thus a special form of the latter. Morphology The fruiting bodies, ascocarps appear in the form of Pseudothecium, pseudothecia. They are solitary and embedded into the host plant tissue. A pseudothecium has small dark hairs around its opening, and contains pseudoparaphyses along with ascus, asci. The asci contain eight haploid ascospores. The haploid chromosome number of ''V. inaequalis'' is seven. Life cycle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apple Scab
Apple scab is a common disease of plants in the rose family ( Rosaceae) that is caused by the ascomycete fungus ''Venturia inaequalis''. While this disease affects several plant genera, including ''Sorbus, Cotoneaster,'' and '' Pyrus'', it is most commonly associated with the infection of ''Malus'' trees, including species of flowering crabapple, as well as cultivated apple. The first symptoms of this disease are found in the foliage, blossoms, and developing fruits of affected trees, which develop dark, irregularly-shaped lesions upon infection. Although apple scab rarely kills its host, infection typically leads to fruit deformation and premature leaf and fruit drop, which enhance the susceptibility of the host plant to abiotic stress and secondary infection.Jha, G., Thakur, K., & Thakur, P. (2009). The ''Venturia'' Apple Pathosystem: Pathogenicity Mechanisms and Plant Defense Responses. ''Journal of Biomedicine and Biotechnology'', 2009. doi:10.1155/2009/680160 The reduction o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire Blight
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. The causal pathogen is ''Erwinia amylovora'', a Gram-negative bacterium in the genus ''Erwinia'', order Enterobacterales. It is a short rod with rounded ends and many peritrichous flagellae. Pears are the most susceptible, but apples, loquat, crabapples, quinces, hawthorn, cotoneaster, ''Pyracantha'', raspberry and some other rosaceous plants are also vulnerable. The disease is believed to be indigenous to North America, from where it spread to most of the rest of the world. Fire blight is not believed to be present in Australia though it might possibly exist there. It has been a major reason for a long-standing embargo on the importation of New Zealand apples to Australia. Japan was likewise believed to b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire Blight
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. The causal pathogen is ''Erwinia amylovora'', a Gram-negative bacterium in the genus ''Erwinia'', order Enterobacterales. It is a short rod with rounded ends and many peritrichous flagellae. Pears are the most susceptible, but apples, loquat, crabapples, quinces, hawthorn, cotoneaster, ''Pyracantha'', raspberry and some other rosaceous plants are also vulnerable. The disease is believed to be indigenous to North America, from where it spread to most of the rest of the world. Fire blight is not believed to be present in Australia though it might possibly exist there. It has been a major reason for a long-standing embargo on the importation of New Zealand apples to Australia. Japan was likewise believed to b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrips
Thrips ( order Thysanoptera) are minute (mostly long or less), slender insects with fringed wings and unique asymmetrical mouthparts. Different thrips species feed mostly on plants by puncturing and sucking up the contents, although a few are predators. Entomologists have described approximately 6,000 species. They fly only weakly and their feathery wings are unsuitable for conventional flight; instead, thrips exploit an unusual mechanism, clap and fling, to create lift using an unsteady circulation pattern with transient vortices near the wings. Many thrips species are pests of commercially important crops. A few species serve as vectors for over 20 viruses that cause plant disease, especially the Tospoviruses. Some species of thrips are beneficial as pollinators or as predators of other insects or mites. In the right conditions, such as in greenhouses, many species can exponentially increase in population size and form large swarms because of a lack of natural predators ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytophthora Cinnamomi
''Phytophthora cinnamomi'' is a soil-borne water mould that produces an infection which causes a condition in plants variously called "root rot", "dieback", or (in certain '' Castanea'' species), "ink disease". The plant pathogen is one of the world's most invasive species and is present in over 70 countries around the world. Host range and symptoms The host range for ''Phytophythora cinnamomi'' is very broad. It is distributed worldwide and causes disease on hundreds of hosts. The disease affects a range of economic groups, including food crops such as avocado and pineapple as well as trees and woody ornamentals such as Fraser firs, shortleaf pines, loblolly pines, azaleas, camellia, boxwood, causing root rot and dieback. It is a root pathogen that causes root rot and death of host plants. Some symptoms include: wilting, decreased fruit size, decrease in yield, collar rot, gum exudation, necrosis, leaf chlorosis, leaf curl, and stem cankers. Another symptom is that it can cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oomycete
Oomycota forms a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms, called oomycetes (). They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction of an oospore is the result of contact between hyphae of male antheridia and female oogonia; these spores can overwinter and are known as resting spores. Asexual reproduction involves the formation of chlamydospores and sporangia, producing motile zoospores. Oomycetes occupy both saprophytic and pathogenic lifestyles, and include some of the most notorious pathogens of plants, causing devastating diseases such as late blight of potato and sudden oak death. One oomycete, the mycoparasite '' Pythium oligandrum'', is used for biocontrol, attacking plant pathogenic fungi. The oomycetes are also often referred to as water molds (or water moulds), although the water-preferring nature which led to that name is not true of most species, which are terrestrial pathogens. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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