|
Lesser Knapweed Flower Weevil
''Larinus minutus'' is a species of true weevil known as the lesser knapweed flower weevil. It is used as an agent of biological pest control against noxious knapweeds, especially diffuse knapweed (''Centaurea diffusa'') and spotted knapweed. The adult weevil is dark mottled brown with a long snout. It is long in total. It is active throughout the summer with a 14-week maximum adult lifespan. During this time the female lays up to 130 eggs, depositing them in the knapweed flower head. The larva emerges and burrows into the flower head where it feeds on the developing seeds. The larva damages the plant by reducing seed production (all of the seeds of diffuse knapweed and 25-100% of spotted knapweed) and the adult does damage by defoliating the plant as it feeds on the leaves prior to flowering. After flowering, adult weevils switch to feeding on flowers. In spotted and diffuse knapweed, ''L. minutus'' directly consumes another biological control agent released to control the spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal
Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motility, able to move, can Sexual reproduction, reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of Cell (biology), cells, the blastula, during Embryogenesis, embryonic development. Over 1.5 million Extant taxon, living animal species have been Species description, described—of which around 1 million are Insecta, insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have Ecology, complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a Symmetry in biology#Bilate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centaurea Diffusa
''Centaurea diffusa'', also known as diffuse knapweed, white knapweed or tumble knapweed, is a member of the genus ''Centaurea'' in the family Asteraceae. This species is common throughout western North America but is not actually native to the North American continent, but to the eastern Mediterranean. Description Diffuse knapweed is an annual or biennial plant, generally growing to between 10 and 60 cm in height. It has a highly branched stem and a large taproot, as well as a basal rosette of leaves with smaller leaves alternating on the upright stems. Flowers are usually white or pink and grow out of urn-shaped heads carried at the tips of the many branches. Diffuse knapweed often assumes a short rosette form for one year, reaching maximum size, then rapidly growing and flowering during the second year. A single plant can produce approximately 18,000 seeds. Synonyms * ''Centaurea microcalathina'' Tarassov * ''Centaurea cycladum'' Heldr. * ''Centaurea parviflora'' Sib ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lixinae
Lixinae is a subfamily of true weevils, included in the Molytinae in many older treatments. They are mainly root feeders, although some develop in flower buds or stems. Several species are used in biological control of invasive weeds, namely knapweeds (''Centaurea''). Characteristics include tarsal claws that are fused at the base, and labial palps are short and telescoping. The body is elongate shape, as for some other weevils. Each tibia bears an uncus (small hook) on its distal end. The rostrum is forwardly directed. Genesis Bearing in mind modern geographical distribution of Lixinae and its feeding links, it is considered to be that this subfamily appeared in Euroasian lands, when the area of Tethys Ocean demenished. Probably, lixine weevils formed as group in the arid conditions of the deserts of Ancient Mediterranean. From here pra-lixine spread out the over dryland. Taxonomy There are three tribes. The largest of these by far are the Cleonini, sometimes ranked as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urophora Quadrifasciata
''Urophora quadrifasciata'' is a species of tephritid or fruit flies in the genus ''Urophora'' of the family Tephritidae. The host plant for the larvae is usually a knapweed (''Centaurea'' sp), and because of this, it is used to control ''Centaurea stoebe''. Distribution Europe & Kazakhstan, North Africa & Iran; introduced North America & Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma .... References Urophora Insects described in 1826 Diptera of Europe Diptera of Asia Diptera of Africa {{Urophora-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urophora Affinis
''Urophora affinis'' is a species of tephritid or fruit flies in the genus ''Urophora'' of the family Tephritidae. It has been released in the United States and Canada as a biocontrol agent to control spotted knapweed. ''U. affinis'' became established in Montana in 1973. Life history ''U. affinis'' is multivoltine and overwinters as a larva in knapweed flower heads. In June, adults oviposit on seed heads. Each female can produce about 120 eggs. It has been shown to reduce seed production in knapweed (spotted and diffuse) by up to 95% Harris P. 1980. Effects of Urophora affinis Frfld, and U. quadrifasciata (Meig.) (Diptera: Tephritidae) on ''Centaurea diffusa'' Lam. and ''C. maculosa'' Lam. (Compositae). Zeitschrift fur Angewandte Entomologie 90:190-201. but that is insufficient for effective management of either species.Powell RD. (1990) The functional forms of density-dependent birth and death rates in diffuse knapweed (Centaurea diffusa) explain why it has not been controlled b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The larva's appearance is generally very different from the adult form (''e.g.'' caterpillars and butterflies) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the larval stage will consume food to fuel their transition into the adult form. In some organisms like polychaetes and barnacles, adults are immobil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Head (botany)
A pseudanthium (Greek for "false flower"; ) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, composite flowers, or capitula, which are special types of inflorescences in which anything from a small cluster to hundreds or sometimes thousands of flowers are grouped together to form a single flower-like structure. Pseudanthia take various forms. The real flowers (the florets) are generally small and often greatly reduced, but the pseudanthium itself can sometimes be quite large (as in the heads of some varieties of sunflower). Pseudanthia are characteristic of the daisy and sunflower family (Asteraceae), whose flowers are differentiated into ray flowers and disk flowers, unique to this family. The disk flowers in the center of the pseudanthium are actinomorphic and the corolla is fused into a tube. Flowers on the periphery are zygomorp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centaurea Maculosa
''Centaurea stoebe'', the spotted knapweed or panicled knapweed, is a species of ''Centaurea'' native to eastern Europe, although it has spread to North America, where it is considered an invasive species. It forms a tumbleweed, helping to increase the species' reach, and the seeds are also enabled by a feathery pappus. Description ''Centaurea stoebe'' is a biennial or short-lived perennial plant, and it usually has a stout taproot and pubescent stems when young. It has pale and deeply-lobed leaves covered in fine short hairs. First-year plants produce a basal rosette, alternate, up to long, deeply divided into lobes. It produces a stem in its second year of growth. Stem leaves are progressively less lobed, getting smaller toward the top. The stem is erect or ascending, slender, hairy and branching, and can grow up to tall. Protruding from black-tipped sepals, the flower blooms from July to September. The flower head is wide, with vibrant pink to lavender (or more rarely white ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centaurea
''Centaurea'' () is a genus of over 700 species of herbaceous thistle-like flowering plants in the family Asteraceae. Members of the genus are found only north of the equator, mostly in the Eastern Hemisphere; the Middle East and surrounding regions are particularly species-rich. In the western United States, yellow starthistles are an invasive species. Around the year 1850, seeds from the plant had arrived to the state of California. It is believed that those seeds came from South America. Common names Common names for this genus are centaury, centory, starthistles, knapweeds, centaureas and the more ambiguous "bluets"; a vernacular name used for these plants in parts of England is "loggerheads" (common knapweed). The ''Plectocephalus'' group – possibly a distinct genus – is known as basketflowers. "Cornflower" is used for a few species, but that term more often specifically means either '' C. cyanus'' (the annual cornflower) or ''Centaurea montana'' (the perennial c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthropod
Arthropods (, (gen. ποδός)) are invertebrate animals with an exoskeleton, a Segmentation (biology), segmented body, and paired jointed appendages. Arthropods form the phylum Arthropoda. They are distinguished by their jointed limbs and Arthropod cuticle, cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate. The arthropod body plan consists of segments, each with a pair of appendages. Arthropods are bilaterally symmetrical and their body possesses an exoskeleton, external skeleton. In order to keep growing, they must go through stages of moulting, a process by which they shed their exoskeleton to reveal a new one. Some species have wings. They are an extremely diverse group, with up to 10 million species. The haemocoel, an arthropod's internal cavity, through which its haemolymph – analogue of blood – circulates, accommodates its interior Organ (anatomy), organs; it has an open circulatory system. Like their exteriors, the internal or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noxious Weed
A noxious weed, harmful weed or injurious weed is a weed that has been designated by an agricultural or other governing authority as a plant that is injurious to agricultural or horticultural crops, natural habitats or ecosystems, or humans or livestock. Most noxious weeds have been introduced into an ecosystem by ignorance, mismanagement, or accident. Some noxious weeds are native. Typically they are plants that grow aggressively, multiply quickly without natural controls (native herbivores, soil chemistry, etc.), and display adverse effects through contact or ingestion. Noxious weeds are a large problem in many parts of the world, greatly affecting areas of agriculture, forest management, nature reserves, parks and other open space. Many noxious weeds have come to new regions and countries through contaminated shipments of feed and crop seeds or were intentionally introduced as ornamental plants for horticultural use. Some "noxious weeds", such as ragwort, produce copious amou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Pest Control
Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also involves an active human management role. It can be an important component of integrated pest management (IPM) programs. There are three basic strategies for biological pest control: classical (importation), where a natural enemy of a pest is introduced in the hope of achieving control; inductive (augmentation), in which a large population of natural enemies are administered for quick pest control; and inoculative (conservation), in which measures are taken to maintain natural enemies through regular reestablishment. Natural enemies of insect pests, also known as biological control agents, include predators, parasitoids, pathogens, and competitors. Biological control agents of plant diseases are most often referred to as antagonists. Biologic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
