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Yellow Starthistle Hairy Weevil
''Eustenopus villosus'' is a species of true weevil known as the yellow starthistle hairy weevil. It is used as an agent of biological pest control against the noxious weed yellow starthistle (''Centaurea solstitialis''). The adult weevil is hairy and brown with white stripes. It is 4 to 6 millimeters long, not including its long snout. The female chews a hole in a closed flower head, deposits an egg inside, and seals the hole with a dark-colored mucilage. This visible hole can change the shape of the flower head as it grows. The larva emerges from its egg in about three days and begins to feed on the flower parts and developing seeds. In just over two weeks the larva can destroy all or nearly all of the developing seeds. It uses the scraps to build a chamber in which it pupa A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Curculionidae
The Curculionidae are a family of weevils, commonly called snout beetles or true weevils. They are one of the largest animal families with 6,800 genera and 83,000 species described worldwide. They are the sister group to the family Brentidae. They include the bark beetles as the subfamily Scolytinae, which are modified in shape in accordance with their wood-boring lifestyle. They do not much resemble other weevils, so they were traditionally considered a distinct family, Scolytidae. The family also includes the ambrosia beetles, of which the present-day subfamily Platypodinae was formerly considered the distinct family Platypodidae. Description Adult Curculionidae can be recognised by the well-developed, downwards-curved snout (Rostrum (anatomy), rostrum) possessed by many species, though the rostrum is sometimes short (e.g. Entiminae). They have elbowed Antenna (biology), antennae that end in clubs, and the first antennal segment often fits into a groove in the side of the rost ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Pest Control
Biological control or biocontrol is a method of controlling pests, whether pest animals such as insects and mites, weeds, or pathogens affecting animals or plants by 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 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 insects play an important part in limiting the densities of potential pests. Biological control agents such as these include predators, parasitoids, pathogens, and com ... [...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 harmful to agricultural or horticultural crops, natural habitats or ecosystems, or humans or livestock. Most noxious weeds have been introduced species, introduced into an ecosystem by ignorance, mismanagement, or accident. Some noxious weeds are native, though many localities define them as necessarily being non-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, forestry, forest management, nature reserves, regional park, 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 introd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centaurea Solstitialis
''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. 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 cornflower). The common name "centaury" is sometimes used, although this also refers to the unrelated plant genus '' Centaurium''.Keil (2006), Keil & Ochsmann (2006). The name is said to be in reference to Ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Head (botany)
A pseudanthium (; : pseudanthia) 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 zygomorphic and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mucilage
Mucilage is a thick gluey substance produced by nearly all plants and some microorganisms. These microorganisms include protists which use it for their locomotion, with the direction of their movement always opposite to that of the secretion of mucilage. It is a polar glycoprotein and an exopolysaccharide. Mucilage in plants plays a role in the storage of water and food, seed germination, and thickening membranes. Cacti (and other succulents) and flax seeds are especially rich sources of mucilage. Occurrence Exopolysaccharides are the most stabilising factor for microaggregates and are widely distributed in soils. Therefore, exopolysaccharide-producing "soil algae" play a vital role in the ecology of the world's soils. The substance covers the outside of, for example, unicellular or filamentous green algae and cyanobacteria. Amongst the green algae especially, the group Volvocales are known to produce exopolysaccharides at a certain point in their life cycle. It occu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase of their life cycle. A 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. In the case of smaller primitive arachnids, the larval stage differs by having three instead of four pairs of legs. 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 lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pupa
A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages thereof being egg, larva, pupa, and imago. The processes of entering and completing the pupal stage are controlled by the insect's hormones, especially juvenile hormone, prothoracicotropic hormone, and ecdysone. The act of becoming a pupa is called pupation, and the act of emerging from the pupal case is called eclosion or emergence. The pupae of different groups of insects have different names such as ''chrysalis'' for the pupae of butterflies and ''tumbler'' for those of the mosquito family. Pupae may further be enclosed in other structures such as cocoons, nests, or shells. Position in life cycle The pupal stage follows the larval stage, or in some cases a prepupal stage, and precedes adulthood ('' imago'') in insects with compl ... [...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 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insects Used For Control Of Invasive Plants
Insects (from Latin ') are hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of jointed legs, compound eyes, and a pair of antennae. Insects are the most diverse group of animals, with more than a million described species; they represent more than half of all animal species. The insect nervous system consists of a brain and a ventral nerve cord. Most insects reproduce by laying eggs. Insects breathe air through a system of paired openings along their sides, connected to small tubes that take air directly to the tissues. The blood therefore does not carry oxygen; it is only partly contained in vessels, and some circulates in an open hemocoel. Insect vision is mainly through their compound eyes, with additional small ocelli. Many insects can hear, using tympanal organs, which may be on the legs or other parts of the body. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
