Sympherobius Barberi Research Articles

Native, naturalized and commercial predators evaluated for use against Diaphorina citri

Diaphorina citri Kuwayama (Hemiptera: Liviidae), is a key pest of citrus associated with the yet uncurable Huanglongbing (HLB) disease, that is threatening worldwide citrus production. Control of D. citri has hitherto relied on chemical insecticides and on the use of the parasitoid Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae). However, use of insecticides is problematic due to environmental and social issues, especially where D. citri is mostly spread in residential areas, and use of T. radiata has resulted in mixed success. Therefore, there is an urgent need to find sustainable and complementary practices to control this pest. Generalist predators, including green lacewings and coccinellids, have been frequently associated to D. citri in field surveys, yet they have rarely been tested. We have tested the predation capability under laboratory, greenhouse and semi-field conditions, of five predators: the green lacewings Chrysoperla comanche (Banks) and C. rufilabris Burmeister (Neuroptera: Chrysopidae), the coccinellids Diomus pumilio Weise and Rhyzobius lophanthae (Blaisdell) (Coleoptera: Coccinellidae) and the brown lacewing Sympherobius barberi Banks (Neuroptera: Hemerobiidae). All of them were capable of feeding on D. citri and reduce its populations under laboratory conditions, but critical differences emerged in greenhouse and field cages, with some predators (the green lacewings and D. pumilio) being the most effective. We discuss possible ways of utilizing these predators as an additional biological control tool to address current limitations of D. citri control in commercial groves, in residential areas and at the urban-agricultural interface.

Effectiveness of the Brown Lacewing, Sympherobius barberi Banks as a Biological Control Agent of the Asian Citrus Psyllid Diaphorina citri Kuwayama.

The Asian citrus psyllid (ACP) Diaphorina citri Kuwayama is an economically important pest of citrus because it vectors the causal pathogens of huanglongbing (HLB) or citrus greening disease. Biological control is an important component of citrus pest management but requires consistent strengthening of its impact on pest complex. The brown lacewing Sympherobius barberi Banks is a known predator of several insect pests from Asia, Europe, and America. However, there is not much information about its effectiveness against D. citri. We evaluated S. barberi against the D. citri and frozen eggs of the Mediterranean flour moth Ephestia kuehniella, the latter is a common diet used for rearing predators in laboratories. Adult S. barberi successfully fed on D. citri eggs and nymphs under both light and dark conditions. Diaphorina citri was also suitable for the development and reproduction of S. barberi except for slightly prolonged larval development compared with E. kuehniella diet. The egg hatch from the total number of eggs laid on D. citri and E. kuehniella diets averaged 65% and 52%, respectively. Females laid 64% eggs on dimpled white paper compared to 36% combined on plain paper and leaves of citrus, orange jasmine, eggplant and cantaloupe. Sympherobius barberi released at densities of 2–6 adults against eggs and nymphs of D. citri on infested orange jasmine plants in the cages provided a reduction of 43–81% in the number of provided eggs or nymphs. In the field tests on D. citri infested citrus trees, reduction averaged 35% in five cohorts in which developing colonies of 28–32 nymphs were provided to one S. barberi per cage. Findings suggest the significant potential of S. barberi as a predator of D. citri and to contribute to reducing huanglongbing.

Enemigos naturales de Dactylopius Opuntiae (Cockerell) en opuntia ficus-indica (l.) Miller en el centro de México

El nopal Opuntia ficus-indica se cultiva con diversos propósitos en el mundo, mientras que en México, principal productor y consumidor mundial, particularmente se consume como verdura (nopalitos). La producción de nopalitos se ubica, principalmente, en los alrededores de la Ciudad de México donde las cochinillas silvestres Dactylopius spp. son de los insectos más nocivos para el cultivo. El control químico es el método de más uso por los productores, aunque el control biológico podría ser útil para un manejo integrado de plagas. No obstante, los estudios taxonómicos sobre las especies de cochinilla y sus enemigos naturales en México no son abundantes. En esta investigación se planteó conocer las especies presentes de Dactylopius y sus enemigos naturales en Tlalnepantla, Morelos, una de las áreas de mayor producción de nopalitos en México. Se seleccionaron 30 sitios distribuidos en esta región y se establecieron cinco sitios para monitoreo de enemigos naturales cada dos semanas durante un año. La única especie de cochinilla silvestre del nopal que se encontró correspondió a Dactylopius opuntiae (Cockerell), los enemigos naturales en orden de abundancia fueron Leucopis bellula, Sympherobius barberi, Laetilia coccidivora, Hyperaspis trifurcata, Salpingogaster cochenillivorus, Sympherobius angustus y Chilocorus cacti. Se proporcionan descripciones de biología de los enemigos naturales en campo y laboratorio. Diversos factores relacionados con el manejo del cultivo tuvieron un efecto sobre las poblaciones de D. opuntiae y sus enemigos naturales.

A review of the Neuroptera of the Galápagos Islands with a new record for Sympherobius barberi (Banks) (Hemerobiidae)

A checklist of species of Neuroptera described and (or) recorded from the Galápagos Islands, Ecuador, is presented together with a review of existing records. Sympherobius barberi (Banks) is recorded from the Galápagos Islands for the first time. This also constitutes the first record of the genus Sympherobius from the islands. Comparisons have been made between the Galápagos specimens, the type specimen of the species, and specimens from Peru, Mexico, and the southern United States of America. Illustrations of habitus and genitalic structures, as well as a diagnosis and a discussion of the species are also given. Additional distributional data and illustrations are provided for Chrysopa wollebaeki Esben-Petersen, Megalomus darwini Banks, and Myrmeleon perpilosus Banks. A lectotype is designated for Megalomus darwini Banks. Keys for identification are given for all species known from the islands.

Effect of Pesticide Residues on the Natural Enemies of Citrus Mealybug12

The toxic residual activities of four pesticides, phosmet, carbaryl, diazinon and dimethoate, were tested against natural enemies of the citrus mealybug, Planococcus citri (Risso). Species tested included four parasites, Pauridia peregrina Timberlake, Leptomastidea abnormis (Girault), Leptomastix dactylopii Howard, and Anagyrus pseudococci (Girault), and two predators, Cryptolaemus montrouzieri Mulsant and Sympherobius barberi (Banks). These natural enemies were exposed 24 h to pesticide residues on leaves of commercially treated citrus at intervals of 1, 9, 16, 23, and 30 days posttreatment to determine their susceptibility to and the persistence of toxic residues. Phosmet and carbaryl had significantly high toxic residual activity up to 30 days posttreatment against the majority of natural enemies tested. Diazinon and dimethoate toxic residue activity decreased significantly in 9 days against the majority of species tested.

Citrus Mealybug: Effect of Pesticide Residues on Adults of the Natural Enemy Complex12

Four parasites of the citrus mealybug, Planococcus citri (Risso), which included Pauridia peregrina Timberlake, Leptomastix dactylopii Howard, Leptomastidea abnormis (Girault), and Anagyrus pseudococci (Girault) and 2 predators Cryptolaemus montrouzieri Mulsant and Sympherobius barberi (Banks) were exposed for 24 h to pesticide residues on leaves of commercially treated citrus in Texas. L. abnormis and P. peregrina were the most susceptible species tested while C. montrouzieri was the most tolerant. Pesticides tested included methidathion, carbophenothion, azinphosmethyl, chlorobenzilate, ethion, and citrus oil. The toxic residual activity of azinphosmethyl-oil combination gave the highest natural enemy mortality over a 35-day posttreatment period, while a chlorobenzilate-oil combination resulted in the lowest mortality.