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Specific Replant Disease
Specific replant disease (also known as sick soil syndrome) is a malady that manifests itself when susceptible plants such as apples, pears, plums, cherries and roses are placed into soil previously occupied by a related species. The exact causes are not known, but in the first year the new plants will grow poorly. Root systems are weak and may become blackened, and plants may fail to establish properly. One theory is that replant disease is due to a whole menagerie of tree pathogens — fungi, bacteria, nematodes, viruses and other organisms. These parasites target the living tissues of the mature tree, hastening senility and death, and survive in the soil and decaying roots after the tree has died. Putting a young traumatized tree with an immature root system into this broth of pathogens can be too much for an infant tree to cope with. Any new root growth is rapidly and heavily colonized, so that shoot growth is virtually zero. This is especially true if it is on a dwarfing roots ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apple (fruit)
An apple is a round, edible fruit produced by an apple tree (''Malus'' spp.). Fruit trees of the orchard or domestic apple (''Malus domestica''), the most widely grown in the genus, are cultivated worldwide. The tree originated in Central Asia, where its wild ancestor, '' Malus sieversii'', is still found. Apples have been grown for thousands of years in Eurasia before they were introduced to North America by European colonists. Apples have cultural significance in many mythologies (including Norse and Greek) and religions (such as Christianity in Europe). Apples grown from seeds tend to be very different from those of their parents, and the resultant fruit frequently lacks desired characteristics. For commercial purposes, including botanical evaluation, apple cultivars are propagated by clonal grafting onto rootstocks. Apple trees grown without rootstocks tend to be larger and much slower to fruit after planting. Rootstocks are used to control the speed of growth and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crop Rotation
Crop rotation is the practice of growing a series of different types of crops in the same area across a sequence of growing seasons. This practice reduces the reliance of crops on one set of nutrients, pest and weed pressure, along with the probability of developing resistant pests and weeds. Growing the same crop in the same place for many years in a row, known as monocropping, gradually depletes the soil of certain nutrients and promotes the proliferation of specialized pest and weed populations adapted to that crop system. Without balancing nutrient use and diversifying pest and weed communities, the productivity of monocultures is highly dependent on external inputs that may be harmful to the soil's fertility. Conversely, a well-designed crop rotation can reduce the need for Fertilizer, synthetic fertilizers and herbicides by better using ecosystem services from a diverse set of crops. Additionally, crop rotations can improve soil structure and Soil organic matter, organic m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pear Tree Diseases
Pears are fruits produced and consumed around the world, growing on a tree and harvested in late summer into mid-autumn. The pear tree and shrub are a species of genus ''Pyrus'' , in the family Rosaceae, bearing the pomaceous fruit of the same name. Several species of pears are valued for their edible fruit and juices, while others are cultivated as trees. The tree is medium-sized and native to coastal and mildly temperate regions of Europe, North Africa, and Asia. Pear wood is one of the preferred materials in the manufacture of high-quality woodwind instruments and furniture. About 3,000 known varieties of pears are grown worldwide, which vary in both shape and taste. The fruit is consumed fresh, canned, as juice, dried, or fermented as perry. Etymology The word ''pear'' is probably from Germanic ''pera'' as a loanword of Vulgar Latin ''pira'', the plural of ''pirum'', akin to Greek ''apios'' (from Mycenaean ''ápisos''), of Semitic origin (''pirâ''), meaning "fruit" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apple Tree Diseases
An apple is a round, edible fruit produced by an apple tree (''Malus'' spp.). Fruit trees of the orchard or domestic apple (''Malus domestica''), the most widely grown in the genus, are cultivated worldwide. The tree originated in Central Asia, where its wild ancestor, ''Malus sieversii'', is still found. Apples have been grown for thousands of years in Eurasia before they were introduced to North America by European colonists. Apples have cultural significance in many mythologies (including Norse and Greek) and religions (such as Christianity in Europe). Apples grown from seeds tend to be very different from those of their parents, and the resultant fruit frequently lacks desired characteristics. For commercial purposes, including botanical evaluation, apple cultivars are propagated by clonal grafting onto rootstocks. Apple trees grown without rootstocks tend to be larger and much slower to fruit after planting. Rootstocks are used to control the speed of growth and the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Pathogens And Diseases
Plants are the eukaryotes that form the kingdom Plantae; they are predominantly photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with cyanobacteria to produce sugars from carbon dioxide and water, using the green pigment chlorophyll. Exceptions are parasitic plants that have lost the genes for chlorophyll and photosynthesis, and obtain their energy from other plants or fungi. Most plants are multicellular, except for some green algae. Historically, as in Aristotle's biology, the plant kingdom encompassed all living things that were not animals, and included algae and fungi. Definitions have narrowed since then; current definitions exclude fungi and some of the algae. By the definition used in this article, plants form the clade Viridiplantae (green plants), which consists of the green algae and the embryophytes or land plants ( hornworts, liverworts, mosses, lycophytes, ferns, conifers and other gymno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chloropicrin
Chloropicrin, also known as PS (from Port Sunlight) and nitrochloroform, is a chemical compound currently used as a broad-spectrum antimicrobial, fungicide, herbicide, insecticide, and nematicide. It was used as a poison gas in World War I and the Russian military has been accused of using it in the Russo-Ukrainian War. Its chemical structural formula is . Synthesis Chloropicrin was discovered in 1848 by Scottish chemist John Stenhouse. He prepared it by the reaction of sodium hypochlorite with picric acid: Because of the precursor used, Stenhouse named the compound chloropicrin, although the two compounds are structurally dissimilar. Today, chloropicrin is manufactured by the reaction of nitromethane with sodium hypochlorite: Reaction of chloroform and nitric acid also yields chloropicrin: Properties Chloropicrin's chemical formula is and its molecular weight is 164.38 grams/mole. Pure chloropicrin is a colorless liquid, with a boiling point of 112 °C. Chloropicri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromomethane
Bromomethane, commonly known as methyl bromide, is an organobromine compound with formula C H3 Br. This colorless, odorless, nonflammable gas is produced both industrially and biologically. It is a recognized ozone-depleting chemical. According to the IPCC Fifth Assessment Report, it has a global warming potential of 2. The compound was used extensively as a pesticide until being phased out by most countries in the early 2000s. From a chemistry perspective, it is one of the halomethanes. Occurrence and manufacture Marine organisms are estimated to produce 56,000 tonnes annually. It is also produced in small quantities by certain terrestrial plants, such as members of the family Brassicaceae. In 2009, an estimated 24,000 tonnes of methyl bromide were produced. Its production was curtailed by the Montreal Protocol, such that in 1983, production was nearly twice that of 2009 levels. It is manufactured by treating methanol with bromine in the presence of sulfur or hydrogen sulf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Almond
The almond (''Prunus amygdalus'', Synonym (taxonomy)#Botany, syn. ''Prunus dulcis'') is a species of tree from the genus ''Prunus''. Along with the peach, it is classified in the subgenus ''Amygdalus'', distinguished from the other subgenera by corrugations on the shell (Fruit anatomy#Endocarp, endocarp) surrounding the seed. The fruit of the almond is a drupe, consisting of an outer hull and a Pyrena, hard shell with the seed, which is not a nut (fruit), true nut. ''Shelling'' almonds refers to removing the shell to reveal the seed. Almonds are sold shelled or unshelled. Blanching (cooking), Blanched almonds are shelled almonds that have been treated with hot water to soften the seedcoat, which is then removed to reveal the white embryo. Once almonds are cleaned and processed, they can be stored for around a year if kept refrigerated; at higher temperatures they will become rancidification, rancid more quickly. Almonds are used in many cuisines, often featuring prominently i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apricot
An apricot (, ) is a fruit, or the tree that bears the fruit, of several species in the genus ''Prunus''. Usually an apricot is from the species '' P. armeniaca'', but the fruits of the other species in ''Prunus'' sect. ''Armeniaca'' are also called apricots. In 2022, world production of apricots was 3.9 million tonnes, led by Turkey with 21% of the total. Etymology ''Apricot'' first appeared in English in the 16th century as ''abrecock'' from the Middle French or later , from Spanish '' albaricoque'' and Catalan , in turn from Arabic (, ), from Byzantine Greek (, ), derived from late Greek (, ) from Latin () (, ). Description The apricot is a small tree, tall, with a trunk up to in diameter and a dense, spreading canopy. The leaves are ovate, long, and wide, with a rounded base, a pointed tip, and a finely serrated margin. The flowers are in diameter, with five white to pinkish petals; they are produced singly or in pairs in early spring before the leaves. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peach
The peach (''Prunus persica'') is a deciduous tree first domesticated and Agriculture, cultivated in China. It bears edible juicy fruits with various characteristics, most called peaches and the glossy-skinned, non-fuzzy varieties called nectarines. Peaches and #Nectarines, nectarines are the same species, though they are regarded commercially as different fruits. The tree is regarded as handsome and is planted in gardens for its springtime blooms in addition to fruit production. The peach tree is relatively short lived, usually not exceeding twenty years of age. However, the peach fruit is regarded as a symbol of longevity in several East Asian cultures. The specific name ''persica'' refers to its widespread cultivation in Persia (modern-day Iran), from where it was transplanted to Europe and in the 16th century to the Americas. It belongs to the genus ''Prunus'', which also includes the cherry, apricot, almond, and plum, and which is part of the Rosaceae, rose family. The p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quince
The quince (; ''Cydonia oblonga'') is the sole member of the genus ''Cydonia'' in the Malinae subtribe (which contains apples, pears, and other fruits) of the Rosaceae family. It is a deciduous tree that bears hard, aromatic bright golden-yellow pome fruit, similar in appearance to a pear. Ripe quince fruits are hard, tart, and astringent. They are eaten raw or processed into jam, quince cheese, or alcoholic drinks. The quince tree is sometimes grown as an ornamental plant for its attractive pale pink blossoms and as a miniature bonsai plant. In ancient Greece, the word for quince was used ribaldly by poets such as Aristophanes to signify teenage breasts. Description Quinces are shrubs or small trees up to tall and wide. Young twigs are covered in a grey down. The leaves are oval, and are downy on the underside. The solitary flowers, produced in late spring after the leaves, are white or pink. The ripe fruit is aromatic but remains hard; gritty stone cells are disperse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medlar
''Mespilus germanica'', known as the medlar or common medlar, is a large shrub or small tree in the rose family Rosaceae. When the genus ''Mespilus'' is included in the genus ''Crataegus'', the correct name for this species is ''Crataegus germanica'' ( L.) Kuntze. The fruit of this tree, also called medlar, has been cultivated since Roman times. It is usually available in winter and eaten when bletted. It may be consumed raw and in a range of cooked dishes. Description Under ideal circumstances, the deciduous plant grows up to tall. Generally, it is shorter and more shrub-like than tree-like. With a lifespan of 30–60 years, the tree is rather short-lived. Its bark is grayish brown with deep vertical cracks forming rectangular plates that tend to lift off. The wild form of ''M. germanica'' is mostly a thorny, more shrub-like than tree-like plant, which is between high. In the cultivated forms, the thorns are usually reduced or even completely absent. In general, the medl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
