TL;DR: Highlights of EPN development for control of insect pests above and below ground include those from foliar, soil surface, cryptic and subterranean habitats.
Abstract: Entomopathogenic nematodes (EPNs) have been utilized in classical, conservation, and augmentative biological control programs. The vast majority of applied research has focused on their potential as inundatively applied augmentative biological control agents. Extensive research over the past three decades has demonstrated both their successes and failures for control of insect pests of crops, ornamental plants, trees and lawn and turf. In this paper we present highlights of their development for control of insect pests above and below ground. The target insects include those from foliar, soil surface, cryptic and subterranean habitats. Advances in mass-production and formulation technology of EPNs, the discovery of numerous efficacious isolates/strains, and the desirability of reducing pesticide usage have resulted in a surge of commercial use and development of EPNs. Commercially produced EPNs are currently in use for control of scarab larvae in lawns and turf, fungus gnats in mushroom production, invasive mole crickets in lawn and turf, black vine weevil in nursery plants, and Diaprepes root weevil in citrus in addition to other pest insects. However, demonstrated successful control of several other insects, often has not lead to capture of a significant share of the pesticide market for these pests.
TL;DR: Diaprepes abbreviatus (L.) is an insidious pest of citrus, sugarcane, and other economic crops of subtropical and tropical areas of the United States and several Caribbean island nations and can be considered a major long-term threat to the survival of several agronomic crops.
Abstract: Diaprepes abbreviatus (L.) is an insidious pest of citrus, sugarcane, and other economic crops of subtropical and tropical areas of the United States and several Caribbean island nations. Host plants associated with this pest, 157 genera, ≍270 species in 59 plant families, are listed. Plants that support egg deposition to adult include Citrus spp.; Arachis hypogaea L., peanut; Sorghum bicolor L. (synonym: S. vulgare ) sorghum; Sorghum bicolor L. ssp. bicolor , guinea corn; Zea mays L., corn; Eugenia uniflora L., Surinam-cherry; Dracaena draco (L.) L. dragon tree; Ipomoea batata (L.) Lam., sweet potato; and Saccharum officinarum L., sugarcane. More than 40 plant species, in 20 families, are associated with larval feeding. As a result of inadequate management strategies and a wide range of adult and larval food plants, D. abbreviatus can be considered a major long-term threat to the survival of several agronomic crops.
TL;DR: Three newly recognized fossil broad-nosed weevils preserved in Early Miocene amber from the Dominican Republic are described, suggesting an eastward directed process of island colonization and likely speciation of members of Diaprepes [FZ2017], given that most extant relatives occur throughout the Lesser Antilles.
Abstract: BACKGROUND Using syntactic and semantic conventions of the taxonomic concept approach (Franz et al. 2015), we describe three newly recognized fossil broad-nosed weevils (Coleoptera: Curculionidae: Entiminae) preserved in Early Miocene amber (ca. 20.4-16.0 mya) from the Dominican Republic: Scelianoma compactasp. n. sec. Franz & Zhang (2017) (henceforth abbreviated as [FZ2017]), Tropirhinus palpebratussp. n. [FZ2017], and Diaprepes anticussp. n. [FZ2017]. The taxonomic assignment of the amber inclusions is grounded in a preceding phylogenetic analysis by Franz (2012). As many as 88 of the 143 therein identified characters were coded for the fossils, whose traits are largely congruent with those present in extant congeners while also differing in ways that justify their new nomenclatural and taxonomic status. NEW INFORMATION We present detailed images, descriptions, and phylogenetically informed diagnoses for the three new species-level entities, along with logically consistent Region Connection Calculus (RCC-5) alignments of the amended genus-level classifications for Scelianoma Franz and Giron 2009 [FZ2017], Tropirhinus Schoenherr 1823 [FZ2017], and Diaprepes Schoenherr 1823 [FZ2017] - in relation to 2-4 preceding classifications published in 1982-2012. The description of Scelianoma compacta [FZ2017] from Hispaniola is indicative of a more widespread historical range of Scelianoma [FZ2017] than reflected in the extant, southwestern Puerto Rican Scelianoma elydimorpha Franz and Giron 2009 sec. Franz and Giron (2009). The presence of Diaprepes anticus [FZ2017] in Hispaniola during the Early Miocene suggests an eastward directed process of island colonization and likely speciation of members of Diaprepes [FZ2017], given that most extant relatives occur throughout the Lesser Antilles. The herein presented data will facilitate more reliable reconstructions of historical biographic processes thought to have played a prominent role in the diversification of the West Indian and Neotropical mainland broad-nosed weevil lineages.
TL;DR: The results showed that ant predation and nematode parasitism were the dominant mortality factors of caged, 6th instar D. abbreviatus larvae and they declined over time, reaching pretreatment levels at 14 days posttreatment based on a modified Baermann sampling procedure.
TL;DR: The results suggest that S. riobrave has the greatest potential for control of D. abbreviatus, the most severe weevil pest in Florida citrus.
Abstract: The Diaprepes root weevil, Diaprepes abbreviatus (L) is the most severe weevil pest in Florida citrus Entomopathogenic nematodes have effectively suppressed larval populations of D abbreviatus Our objective was to conduct a broad laboratory comparison of entomopathogenic nematodes for virulence toward larvae of D abbreviatus The study was conducted at three temperatures (20, 24, and 29°C) and included nine entomopathogenic species and 17 strains: Heterorhabditis bacteriophora Poinar (Baine, NJ1, Hb, Hbl, HP88, and Lewiston strains), H indica Poinar, Karunakar & David (original and Hom1 strains), H marelatus Liu & Berry (IN and Point Reyes strains), H megidis Poinar, Jackson & Klein (UK211 strain), H zealandica Poinar (NZH3 strain), Steinernema riobrave Cabanillas, Poinar & Raulston (355 strain), S carpocapsae (Weiser) (All strain), S feltiae (Filipjev) (SN and UK76 strains), and S glaseri (Steiner) (NJ43 strain) At 20°C, the greatest mortality was caused by S riobrave although it was not significantly greater than H bacteriophora (Baine), H bacteriophora (Hb), H bacteriophora (Hbl), and H indica (original) At 24 and 29°C, S riobrave caused greater larval mortality than other nematodes tested Two strains of H indica, H bacteriophora (Baine), and S glaseri were next in terms of virulence at 29°C Our results suggest that S riobrave has the greatest potential for control of D abbreviatus