|
Chilling Unit
The chilling requirement of a fruit is the minimum period of cold weather after which a fruit-bearing tree will blossom productively. It is often expressed in chill hours, which can be calculated in different ways, all of which essentially involve adding up the total amount of time in a winter spent at certain temperatures. Some bulbs have chilling requirements to bloom, and some seeds have chilling requirements to sprout. Biologically, the chilling requirement is a way of ensuring that vernalization occurs. Chilling units or chilling hours A ''chilling unit'' in agriculture is a metric of a plant's exposure to chilling temperatures. Chilling temperatures extend from freezing point to, depending on the model, or even .Byrne, D. H., and T. A. Bacon (1992). Chilling estimation: its importance and estimation''. The Texas Horticulturist 18(8):5, 8-9. Retrieved 2010-05-24. Stone fruit trees and certain other plants of temperate climate develop next year's buds in the summer. In t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Weather
Weather is the state of the atmosphere, describing for example the degree to which it is hot or cold, wet or dry, calm or stormy, clear or cloud cover, cloudy. On Earth, most weather phenomena occur in the lowest layer of the planet's atmosphere of Earth, atmosphere, the troposphere, just below the stratosphere. Weather refers to day-to-day temperature, precipitation, and other atmospheric conditions, whereas climate is the term for the averaging of atmospheric conditions over longer periods of time. When used without qualification, "weather" is generally understood to mean the weather of Earth. Weather is driven by atmospheric pressure, air pressure, temperature, and moisture differences between one place and another. These differences can occur due to the effect of Sun angle on climate, Sun's angle at any particular spot, which varies with latitude. The strong temperature contrast between polar and tropical air gives rise to the largest scale atmospheric circulations: the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Texas
Texas ( , ; or ) is the most populous U.S. state, state in the South Central United States, South Central region of the United States. It borders Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the west, and has Mexico-United States border, an international border with the Mexican states of Chihuahua (state), Chihuahua, Coahuila, Nuevo León, and Tamaulipas to the south and southwest. Texas has Texas Gulf Coast, a coastline on the Gulf of Mexico to the southeast. Covering and with over 31 million residents as of 2024, it is the second-largest state List of U.S. states and territories by area, by area and List of U.S. states and territories by population, population. Texas is nicknamed the ''Lone Star State'' for its former status as the independent Republic of Texas. Spain was the first European country to Spanish Texas, claim and control Texas. Following French colonization of Texas, a short-lived colony controlled by France, Mexico ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Bolting (horticulture)
In horticulture, bolting is the production of a flowering stem (or stems) on agricultural and horticultural crops before the harvesting of a crop, at a stage when a plant makes a natural attempt to produce seeds and to reproduce. The flowering stems are usually vigorous extensions of existing leaf-bearing stems; to produce them, a plant diverts resources from producing the edible parts (such as leaves or roots), resulting in changes in flavor and texture, withering, and in general, a poor-quality harvest. Plants that have produced flowering stems in this way are said to have bolted. Crops inclined to bolt include lettuce, basil, beetroot, brassicas, spinach, celery, onion, and leek. Bolting is induced by plant hormones of the gibberellin family, and can occur as a result of several factors, including changes in day length, the prevalence of high temperatures at particular stages in a plant's growth-cycle, and the existence of stresses such as insufficient water or mineral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Carrot
The carrot ('' Daucus carota'' subsp. ''sativus'') is a root vegetable, typically orange in colour, though heirloom variants including purple, black, red, white, and yellow cultivars exist, all of which are domesticated forms of the wild carrot, ''Daucus carota'', native to Europe and Southwestern Asia. The plant probably originated in Iran and was originally cultivated for its leaves and seeds. The carrot is a biennial plant in the umbellifer family, Apiaceae. World production of carrots (combined with turnips) for 2022 was 42 million tonnes, led by China producing 44% of the total. The characteristic orange colour is from beta-carotene, making carrots a rich source of vitamin A. A myth that carrots help people to see in the dark was spread as propaganda in the Second World War, to account for the ability of British pilots to fight in the dark; the real explanation was the introduction of radar. Etymology The word is first recorded in English around 1530 and w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Celery
Celery (''Apium graveolens'' Dulce Group or ''Apium graveolens'' var. ''dulce'') is a cultivated plant belonging to the species ''Apium graveolens'' in the family Apiaceae that has been used as a vegetable since ancient times. The original wild species has been selectively bred over centuries into three primary cultivar groups: stalk celery (Dulce Group), consumed for its fibrous edible stalks; leaf celery (Secalinum Group), grown for its aromatic leaves; and celeriac (Rapaceum Group), cultivated for its large, edible hypocotyl. Celery is characterized by its long, ribbed stalks, pinnate leaves, and small white flowers arranged in umbels. Celery is composed primarily of water (95%) but contains large amounts of vitamin K and negligible fat. The vegetable is commonly consumed raw in salads, cooked in soups and stews, or juiced. Celery seeds, which have a strong, aromatic flavor, are used as a spice or processed into celery salt. Celery is among a small group of foods that may pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Sugar Beet
A sugar beet is a plant whose root contains a high concentration of sucrose and that is grown commercially for sugar production. In plant breeding, it is known as the Altissima cultivar group of the common beet (''Beta vulgaris''). Together with other beet cultivars, such as beetroot and chard, it belongs to the subspecies ''Beta vulgaris'' subsp. ''vulgaris'' but classified as ''var. saccharifera''. Its closest wild relative is the sea beet (''Beta vulgaris'' subsp. ''maritima''). Sugar beets are grown in climates that are too cold for sugarcane. In 2020, Russia, the United States, Germany, France and Turkey were the world's five largest sugar beet producers. In 2010–2011, Europe, and North America except Arctic territories failed to supply the overall domestic demand for sugar and were all net importers of sugar. The US harvested of sugar beets in 2008. In 2009, sugar beets accounted for 20% of the world's sugar production and nearly 30% by 2013. Sugarcane accounts for most ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cabbage
Cabbage, comprising several cultivars of '' Brassica oleracea'', is a leafy green, red (purple), or white (pale green) biennial plant grown as an annual vegetable crop for its dense-leaved heads. It is descended from the wild cabbage ( ''B. oleracea'' var. ''oleracea''), and belongs to the " cole crops" or brassicas, meaning it is closely related to broccoli and cauliflower (var. ''botrytis''); Brussels sprouts (var. ''gemmifera''); and Savoy cabbage (var. ''sabauda''). A cabbage generally weighs between . Smooth-leafed, firm-headed green cabbages are the most common, with smooth-leafed purple cabbages and crinkle-leafed savoy cabbages of both colours being rarer. Under conditions of long sunny days, such as those found at high northern latitudes in summer, cabbages can grow quite large. , the heaviest cabbage was . Cabbage heads are generally picked during the first year of the plant's life cycle, but plants intended for seed are allowed to grow a second year and m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Biennial Plant
A biennial plant is a flowering plant that, generally in a temperate climate, takes two years to complete its biological life cycle. Background In its first year, the biennial plant undergoes primary growth, during which its vegetative structures (leaves, stems, and roots) develop. Usually, the stem of the plant remains short and the leaves are low to the ground, forming a rosette. After one year's growing season, the plant enters a period of dormancy for the colder months. Many biennials require a cold treatment, or vernalization before they will flower. During the next spring or summer, the stem of the biennial plant elongates greatly, or "bolts". The plant then flowers, producing fruits and seeds before it finally dies. There are far fewer biennials than either perennial plants or annual plants. Biennials do not always follow a strict two-year life cycle: most plants in the wild can take three or more years to mature. Rosette leaf size has been found to predict when a pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Chlorophyll
Chlorophyll is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words (, "pale green") and (, "leaf"). Chlorophyll allows plants to absorb energy from light. Those pigments are involved in oxygenic photosynthesis, as opposed to bacteriochlorophylls, related molecules found only in bacteria and involved in anoxygenic photosynthesis. Chlorophylls absorb light most strongly in the blue portion of the electromagnetic spectrum as well as the red portion. Conversely, it is a poor absorber of green and near-green portions of the spectrum. Hence chlorophyll-containing tissues appear green because green light, diffusively reflected by structures like cell walls, is less absorbed. Two types of chlorophyll exist in the photosystems of green plants: chlorophyll ''a'' and ''b''. History Chlorophyll was first isolated and named by Joseph Bienaimé Caventou and Pierre Joseph Pelletier in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Carotenoid
Carotenoids () are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, archaea, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, corn, tomatoes, canaries, flamingos, salmon, lobster, shrimp, and daffodils. Over 1,100 identified carotenoids can be further categorized into two classes xanthophylls (which contain oxygen) and carotenes (which are purely hydrocarbons and contain no oxygen). All are derivatives of tetraterpenes, meaning that they are produced from 8 isoprene units and contain 40 carbon atoms. In general, carotenoids absorb wavelengths ranging from 400 to 550 nanometers (violet to green light). This causes the compounds to be deeply colored yellow, orange, or red. Carotenoids are the dominant pigment in autumn leaf coloration of about 15-30% of tree species, but many plant colors, especially reds and purples, are due to polyphenols. Carotenoids serve two key roles in p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Orange (fruit)
The orange, also called sweet orange to distinguish it from the bitter orange (''Citrus × aurantium''), is the fruit of a tree in the family (biology), family Rutaceae. Botanically, this is the hybrid Citrus × sinensis, ''Citrus'' × ''sinensis'', between the pomelo (''Citrus maxima'') and the mandarin orange (''Citrus reticulata''). The chloroplast genome, and therefore the maternal line, is that of pomelo. There are many related hybrids including of mandarins and sweet orange. The sweet orange has had its full Whole genome sequencing, genome sequenced. The orange originated in a region encompassing Northern and southern China, Southern China, Northeast India, and Myanmar; the earliest mention of the sweet orange was in Chinese literature in 314 BC. Orange trees are widely grown in tropical and subtropical areas for their sweet fruit. The fruit of the Citrus × sinensis, orange tree can be eaten fresh or processed for its juice or fragrant peel (fruit), peel. In 2022, 76 mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cyanamide
Cyanamide is an organic compound with the formula C N2 H2. This white solid is widely used in agriculture and the production of pharmaceuticals and other organic compounds. It is also used as an alcohol-deterrent drug. The molecule features a nitrile group attached to an amino group. Derivatives of this compound are also referred to as cyanamides, the most common being calcium cyanamide (CaCN2). Tautomers and self-condensations Containing both a nucleophilic and electrophilic site within the same molecule, cyanamide undergoes various reactions with itself. Cyanamide exists as two tautomers, one with the connectivity N≡C–NH2 and the other with the formula HN=C=NH (" carbodiimide" tautomer). The N≡C–NH2 form dominates, but in a few reactions (e.g. silylation) the diimide form appears to be important. Cyanamide dimerizes to give 2-cyanoguanidine (dicyandiamide). This dimerization is hindered or reversed by acids and is inhibited by low temperatures. The cyclic trime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
