Psyllidae, the jumping plant lice or psyllids, are a family of small plant-feeding insects that tend to be very host-specific, i.e. each plant-louse species only feeds on one plant species (monophagous) or feeds on a few closely related plants (oligophagous). Together with aphids, phylloxerans, scale insects and whiteflies, they form the group called Sternorrhyncha, which is considered to be the most "primitive" group within the true bugs (Hemiptera). They have traditionally been considered a single family, Psyllidae, but recent classifications divide the group into a total of seven families; the present restricted definition still includes more than 70 genera in the Psyllidae. Psyllid fossils have been found from the Early Permian before the flowering plants evolved. The explosive diversification of the flowering plants in the Cretaceous was paralleled by a massive diversification of associated insects, and many of the morphological and metabolic characters that the flowering plants exhibit may have evolved as defenses against herbivorous insects.
The emerald ash borer, also known by the acronym EAB, is a green buprestid or jewel beetle native to north-eastern Asia that feeds on ash species. Females lay eggs in bark crevices on ash trees, and larvae feed underneath the bark of ash trees to emerge as adults in one to two years. In its native range, it is typically found at low densities and does not cause significant damage to trees native to the area. Outside its native range, it is an invasive species and is highly destructive to ash trees native to Europe and North America. Before it was found in North America, very little was known about emerald ash borer in its native range; this has resulted in much of the research on its biology being focused in North America. Local governments in North America are attempting to control it by monitoring its spread, diversifying tree species, and through the use of insecticides and biological control.
The glassy-winged sharpshooter is a large leafhopper, similar to other species of sharpshooter.
A leafhopper is the common name for any species from the family Cicadellidae. These minute insects, colloquially known as hoppers, are plant feeders that suck plant sap from grass, shrubs, or trees. Their hind legs are modified for jumping, and are covered with hairs that facilitate the spreading of a secretion over their bodies that acts as a water repellent and carrier of pheromones. They undergo a partial metamorphosis, and have various host associations, varying from very generalized to very specific. Some species have a cosmopolitan distribution, or occur throughout the temperate and tropical regions. Some are pests or vectors of plant viruses and phytoplasmas. The family is distributed all over the world, and constitutes the second-largest hemipteran family, with at least 20,000 described species.
Economic entomology is a field of entomology, which involves the study of insects that benefit or harm humans, domestic animals, and crops. Insects that cause losses are termed as pests. Some species can cause indirect damage by spreading diseases and these are termed as vectors. Those that are beneficial include those reared for food such as honey, substances such as lac or pigments and for their role in pollinating crops and controlling pests.
Xylella fastidiosa is an aerobic, Gram-negative bacterium of the monotypic genus Xylella. It is a plant pathogen, and is transmitted exclusively by xylem fluid-feeding sap insects. Many plant diseases are due to symptomatic infections of X. fastidiosa, including bacterial leaf scorch, oleander leaf scorch, coffee leaf scorch (CLS), alfalfa dwarf, phony peach disease, and the economically important Pierce's disease of grapes (PD) and citrus variegated chlorosis (CVC). In Europe, it has attacked olive trees in the Salento area of Southern Italy, causing olive quick decline syndrome (OQDS). While distributions of X. fastidiosa–related diseases are mostly limited to the Americas, outbreaks have occurred in Taiwan, Slovakia, and other countries worldwide.
Septoria malagutii is a fungal plant pathogen infecting potatoes. The casual fungal pathogen is a deuteromycete and therefore has no true sexual stage. As a result, Septoria produces pycnidia, an asexual flask shaped fruiting body, on the leaves of potato and other tuber-bearing spp. causing small black to brown necrotic lesions ranging in size from 1-5mm. The necrotic lesions can fuse together forming large necrotic areas susceptible to leaf drop, early senescence, dieback, and dwarfing. Septoria malagutii has been found only in the Andean countries of Bolivia, Ecuador, Peru, and Venezuela at altitudes of near 3000 meters. Consequently, the fungi grows and disperses best under relatively low temperatures with high humidities, with optimal growth occurring at 20 °C (68 °F). The disease has caused devastation on potato yields in South America and in areas where this disease is common, potato yields have been seen to drop by 60%.
Graphocephala is a large genus of leafhoppers, found from southern Canada to northern South America.
Karl Maramorosch was an Austrian-born American virologist, entomologist, and plant pathologist. A centenarian and polyglot, he conducted research on viruses, mycoplasmas, rickettsiae, and other micro-organisms; and their transmission to plants through insect vectors in many parts of the world. He is the co-author of a textbook on techniques in virology and is the author of numerous papers on the biology and ecology of plant viruses, their hosts, and vectors. He received the Wolf Prize in Agriculture in 1980 for his contribution to the study of crop pathogens.
Parasa lepida, the nettle caterpillar or blue-striped nettle grub, is a moth of the family Limacodidae that was described by Pieter Cramer in 1799. It is a native minor pest found in the Indo-Malayan region, including India, Sri Lanka, Vietnam, Malaysia and Indonesia. It is an introduced pest to urban trees in western Japan.
Philaenus spumarius, the meadow froghopper or meadow spittlebug, is a species of insect belonging to the spittlebug family Aphrophoridae. In Italy and America, it is economically important as one of the vectors of Pierce's Disease .
Portlandia coccinea is a small tree or shrub with bright red flowers endemic to Jamaica. The species was first described in 1788. A population with darker flowers had been considered a subspecies of P. coccinea, but was described as a separate species, P. proctori, in 2003.
Rhopalosiphum rufiabdominale, the rice root aphid or red rice root aphid, is a sap-sucking insect pest with a wide host range and a global distribution. As a member of the superfamily Aphidoidea, it is one of 16 species of the genus Rhopalosiphum. Adults and nymphs are soft-bodied and usually dark green with brown, red, or yellow tones. Like all aphids, reproduction is sexual and asexual, depending on the environmental conditions and host plant. Rice root aphids cause injury to external plant parts, namely the roots or stem, by feeding on plant sap and vector several important plant viruses. The hosts of this pest extend across multiple plant families with most belonging to Rosaceae, Poaceae, and Solanaceae. R. rufiabdominale is universally associated with Prunus species but also infests various field crops, greenhouse vegetables, cannabis, and other ornamental plants. While this aphid originates from east Asia, it spans nearly every continent. Dispersal is particularly widespread across the United States, India, and Australia, with crop damage documented in multiple instances, although economic losses are primarily associated with Japanese rice crops. Nonetheless, it remains a pest of serious concern due to its high mobility, discrete habitat, and adaptive plasticity, giving it the rightful reputation as a successful invader.
Graphocephala atropunctata, commonly known as the blue-green sharpshooter, is a hemipteran bug endemic to California. It carries the phytopathogenic bacteria Xylella fastidiosa which infects the xylem of grape vines causing die-back – known as Pierce's disease. This leads to loss of productivity and economic damage to the California vineyards. Although the bacterium and its damage to grapes had been known in the state since at least 1900, this new vector insect was unknown here until 1997. Suddenly this much more effective vector greatly increased the impact of X. f. and by 1999 Southern California alone was suffering losses of over US $6 million.
Agriculture is a significant sector in California's economy, producing nearly $50 billion in revenue in 2018. There are more than 400 commodity crops grown across California, including a significant portion of all fruits, vegetables, and nuts for the United States. In 2017, there were 77,100 unique farms and ranches in the state, operating across 25.3 million acres of land. The average farm size was 328 acres (133 ha), significantly less than the average farm size in the U.S. of 444 acres (180 ha).
Nicola Jane Spence is the Chief Plant Health Officer and Deputy Director for plant and bee health at the Department for Environment, Food and Rural Affairs.
Ips cembrae, known generally as larch bark beetle or eight-toothed larch bark beetle, is a species of typical bark beetle in the family Curculionidae. Its habitat is Euro-Siberian, ranging from sea level to sub-alpine. It was first recorded in Great Britain in 1955. Populations were said to be found in Japan and China, but further research determined that those were actually Ips subelongatus.
Pecan bacterial leaf scorch is a disease of the pecan tree that is common throughout the production regions of the United States caused by the pathogenic bacterium Xylella fastidiosa subsp. multiplex. The pathogen was initially discovered to be coincidentally associated with symptoms of pecan fungal leaf scorch in 1998 and has subsequently been found to be endemic in the southeastern United States, as well as Arizona, California, and New Mexico.
Saskia A. Hogenhout FRES, is a Dutch professor of entomology and ecology specialising in molecular plant, microbe and insect interactions.
