Diaprepes abbreviatus
Encyclopedia
Diaprepes abbreviatus is a species of weevil
that is native to the Caribbean
, where in Spanish it is colloquially called chichí. It is an agricultural pest in several Caribbean countries. In 1964 this weevil was accidentally introduced in the US state of Florida
where it is at present a major pest of citrus
. It was first discovered in southern California
in 2005, where it is a pest of citrus, avocado
, and nursery stock. It is also known to infest sugarcane
, tuber
-bearing crops such as potato
es, and ornamental plant
s. Common names for the insect include diaprepes root weevil, citrus root weevil and sugarcane rootstock borer weevil.
The adult citrus root weevil is somewhat variable in size but just over 1 cm (0.393700787401575 in) in length on average. Its elytra
are glossy black with large stripes of tiny yellowish-orange scales, and its head and legs are black. It has adhesive pads on its legs which confer the ability to adhere to very smooth surfaces. The larva
is a plump pale grub with a dark head, up to 2.5 cm (0.984251968503937 in) in length. A female weevil might lay 5,000 eggs, depositing them in clusters on leaves, then folding and gluing the leaves together. After a week the larvae emerge from the eggs, fall to the ground, and burrow down to the root
s of the host plant. They feed on the roots for several months, which is very damaging to the plant. While the adult weevil does feed on the foliage of the plant, it is the larvae that do the most damage. They often eat the taproot
of the plant, which can kill it by depriving it of water and nutrients or by making it vulnerable to infection by fungi
, or water moulds such as Phytophthora
. The weevil spreads mainly by "hitchhiking" when infested plants, soil, and containers are moved from site to site.
A variety of agents are being studied as possible biological pest control
for the weevil, including ant
s, parasitic wasp
s, at least one virus
, and Bacillus thuringiensis
. The nematode
Steinernema riobravis is released in irrigation
water in infested fields in Florida to combat the pest. The weevil is difficult to control because each female produces so many offspring.
Weevil
A weevil is any beetle from the Curculionoidea superfamily. They are usually small, less than , and herbivorous. There are over 60,000 species in several families, mostly in the family Curculionidae...
that is native to the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
, where in Spanish it is colloquially called chichí. It is an agricultural pest in several Caribbean countries. In 1964 this weevil was accidentally introduced in the US state of Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
where it is at present a major pest of citrus
Citrus
Citrus is a common term and genus of flowering plants in the rue family, Rutaceae. Citrus is believed to have originated in the part of Southeast Asia bordered by Northeastern India, Myanmar and the Yunnan province of China...
. It was first discovered in southern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
in 2005, where it is a pest of citrus, avocado
Avocado
The avocado is a tree native to Central Mexico, classified in the flowering plant family Lauraceae along with cinnamon, camphor and bay laurel...
, and nursery stock. It is also known to infest sugarcane
Sugarcane
Sugarcane refers to any of six to 37 species of tall perennial grasses of the genus Saccharum . Native to the warm temperate to tropical regions of South Asia, they have stout, jointed, fibrous stalks that are rich in sugar, and measure two to six metres tall...
, tuber
Tuber
Tubers are various types of modified plant structures that are enlarged to store nutrients. They are used by plants to survive the winter or dry months and provide energy and nutrients for regrowth during the next growing season and they are a means of asexual reproduction...
-bearing crops such as potato
Potato
The potato is a starchy, tuberous crop from the perennial Solanum tuberosum of the Solanaceae family . The word potato may refer to the plant itself as well as the edible tuber. In the region of the Andes, there are some other closely related cultivated potato species...
es, and ornamental plant
Ornamental plant
Ornamental plants are plants that are grown for decorative purposes in gardens and landscape design projects, as house plants, for cut flowers and specimen display...
s. Common names for the insect include diaprepes root weevil, citrus root weevil and sugarcane rootstock borer weevil.
The adult citrus root weevil is somewhat variable in size but just over 1 cm (0.393700787401575 in) in length on average. Its elytra
Elytron
An elytron is a modified, hardened forewing of certain insect orders, notably beetles and a few of the true bugs ; in most true bugs, the forewings are instead called hemelytra, as only the basal half is thickened while the apex is membranous...
are glossy black with large stripes of tiny yellowish-orange scales, and its head and legs are black. It has adhesive pads on its legs which confer the ability to adhere to very smooth surfaces. The larva
Larva
A larva 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...
is a plump pale grub with a dark head, up to 2.5 cm (0.984251968503937 in) in length. A female weevil might lay 5,000 eggs, depositing them in clusters on leaves, then folding and gluing the leaves together. After a week the larvae emerge from the eggs, fall to the ground, and burrow down to the root
Root
In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
s of the host plant. They feed on the roots for several months, which is very damaging to the plant. While the adult weevil does feed on the foliage of the plant, it is the larvae that do the most damage. They often eat the taproot
Taproot
A taproot is an enlarged, somewhat straight to tapering plant root that grows vertically downward. It forms a center from which other roots sprout laterally.Plants with taproots are difficult to transplant...
of the plant, which can kill it by depriving it of water and nutrients or by making it vulnerable to infection by fungi
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...
, or water moulds such as Phytophthora
Phytophthora
Phytophthora is a genus of plant-damaging Oomycetes , whose member species are capable of causing enormous economic losses on crops worldwide, as well as environmental damage in natural ecosystems. The genus was first described by Heinrich Anton de Bary in 1875...
. The weevil spreads mainly by "hitchhiking" when infested plants, soil, and containers are moved from site to site.
A variety of agents are being studied as possible biological pest control
Biological pest control
Biological control of pests in agriculture is a method of controlling pests that relies on predation, parasitism, herbivory, or other natural mechanisms...
for the weevil, including ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...
s, parasitic wasp
Parasitic wasp
The term parasitoid wasp refers to a large evolutionary grade of hymenopteran superfamilies, mainly in the Apocrita. They are primarily parasitoids of other animals, mostly other arthropods...
s, at least one virus
Virus
A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...
, and Bacillus thuringiensis
Bacillus thuringiensis
Bacillus thuringiensis is a Gram-positive, soil-dwelling bacterium, commonly used as a biological pesticide; alternatively, the Cry toxin may be extracted and used as a pesticide. B...
. The nematode
Nematode
The nematodes or roundworms are the most diverse phylum of pseudocoelomates, and one of the most diverse of all animals. Nematode species are very difficult to distinguish; over 28,000 have been described, of which over 16,000 are parasitic. It has been estimated that the total number of nematode...
Steinernema riobravis is released in irrigation
Irrigation
Irrigation may be defined as the science of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall...
water in infested fields in Florida to combat the pest. The weevil is difficult to control because each female produces so many offspring.