Two new species and one new combination of Ophiocordyceps (Hypocreales, Ophiocordycipitaceae) in Guizhou.

Ophiocordyceps is the largest genus in Ophiocordycipitaceae and has a broad distribution with high diversity in subtropical and tropical regions. In this study, two new species, pathogenic on lepidopteran larvae are introduced, based on morphological observation and molecular phylogeny. Ophiocordycepsfenggangensissp. nov. is characterised by having fibrous, stalked stroma with a sterile tip, immersed perithecia, cylindrical asci and filiform ascospores disarticulating into secondary spores. Ophiocordycepsliangiisp. nov. has the characteristics of fibrous, brown, stipitate, filiform stroma, superficial perithecia, cylindrical asci and cylindrical-filiform, non-disarticulating ascospores. A new combination Ophiocordycepsmusicaudata (syn. Cordycepsmusicaudata) is established employing molecular analysis and morphological characteristics. Ophiocordycepsmusicaudata is characterised by wiry, stipitate, solitary, paired to multiple stromata, yellowish, branched fertile part, brown stipe, immersed perithecia, cylindrical asci and cylindrical-filiform, non-disarticulating ascospores.

Taxonomic and Phylogenetic Updates on Apiospora: Introducing Four New Species from Wurfbainia villosa and Grasses in China.

Apiospora, an ascomycetous genus in Apiosporaceae, comprises saprobes, endophytes, and pathogens of humans and plants. They have a cosmopolitan distribution with a wide range of hosts reported from Asia. In the present study, we collected and isolated Apiospora species from Wurfbainia villosa and grasses in Guangdong and Yunnan provinces in China. Multi-locus phylogeny based on the internal transcribed spacer, the large subunit nuclear rDNA, the partial translation elongation factor 1-α, and ß-tubulin was performed to clarify the phylogenetic affinities of the Apiospora species. Based on the distinctive morphological characteristics and molecular evidence, Ap. endophytica, Ap. guangdongensis, Ap. wurfbainiae, and Ap. yunnanensis are proposed. Descriptions, illustrations, and notes for the newly discovered species are provided and compared with closely related Apiospora species. An updated phylogeny of Apiospora is presented, along with a discussion on the phylogenetic affinities of ambiguous taxa.

Evaluation of the effectiveness of entomopathogens for the management of wireworms (Coleoptera: Elateridae) on spring wheat.

Wireworms, the larval stage of click beetles (Coleoptera: Elateridae), are serious soil dwelling pests of small grains, corn, sugar beets, and potatoes. Limonius californicus and Hypnoidus bicolor are the predominant wireworm species infesting wheat in Montana, particularly in the 'Golden Triangle' area of north-central Montana. Wireworm populations in field crops are increasing, but currently available insecticides provide only partial control, and no alternative management tools exist. In our study, three entomopathogenic fungi were tested for their efficacy against wireworms in spring wheat at two field locations (Ledger and Conrad, Montana, USA) in 2013. The three fungi (Metarhizium brunneum F52, Beauveria bassiana GHA, and Metarhizium robertsii DWR 346) were evaluated as seed-coat, in-furrow granular, and soil band-over-row drench applications in addition to imidacloprid (Gaucho® 600) seed treatment (as a chemical check), the approach currently being used by growers. Wireworm damage in these treatments was evaluated as standing plant counts, wireworm population surveys, and yield. The three fungi, applied as formulated granules or soil drenches, and the imidacloprid seed treatment all resulted in significantly higher plant stand counts and yields at both locations than the fungus-coated seed treatments or the untreated control. Significant differences were detected among the application methods but not among the species of fungi within each application method. All three fungi, when applied as granules in furrow or as soil drenches, were more effective than when used as seed-coating treatments for wireworm control, and provided an efficacy comparable or superior to imidacloprid. The fungi used in this study provided significant plant and yield protection under moderate wireworm pressure, supporting their value in the management of this pest.

Sustainable management tactics for control of Phyllotreta cruciferae (Coleoptera: Chrysomelidae) on canola in Montana.

The crucifer flea beetle, Phyllotreta cruciferae (Goeze) (Coleoptera: Chrysomelidae), has recently emerged as a serious pest of canola (Brassica napus L.) in Montana. The adult beetles feed on canola leaves, causing many small holes that stunt growth and reduce yield. In 2013, damage to canola seedlings was high (approximately 80%) in many parts of Montana, evidence that when flea beetles emerge in large numbers, they can quickly destroy a young canola crop. In the current study, the effectiveness of several biopesticides was evaluated and compared with two insecticides (deltamethrin and bifenthrin) commonly used as foliar sprays as well as seed treatment with an imidacloprid insecticide for the control of P. cruciferae under field conditions in 2013. The biopesticides used included an entomopathogenic nematode (Steinernema carpocapsae), two entomopathogenic fungi (Beauveria bassiana and Metarhizium brunneum), neem, and petroleum spray oils. The control agents were delivered in combination or alone in a single or repeated applications at different times. The plant-derived compound neem (azadirachtin), petroleum spray oil, and fatty acids (M-Pede) only showed moderate effect, although they significantly reduced leaf injuries caused by P. cruciferae and resulted in higher canola yield than the untreated control. Combined use of B. bassiana and M. brunneum in two repeated applications and bifenthrin in five applications were most effective in reducing feeding injuries and improving yield levels at both trial locations. This indicates that entomopathogenic fungi are effective against P. cruciferae, and may serve as alternatives to conventional insecticides or seed treatments in managing this pest.

Identification of oviposition attractants of the secondary screwworm, Cochliomyia macellaria (F.) released from rotten chicken liver.

The secondary screwworm, Cochliomyia macellaria (F.), is an important blowfly species affecting both livestock and humans. It can transmit pathogenic disease agents mechanically and is an agent of facultative myiasis, which leads to economic losses. The adult flies are attracted to decomposing carcasses, carrion, or rotten meat in order to deposit their eggs, and the hatched larvae develop on these decaying organic materials. This research was aimed to identify volatiles emitted from rotten chicken livers that were reported previously to attract gravid females. In laboratory oviposition assays, gravid females laid significantly more eggs on rotten livers than on fresh livers, and rotten chicken liver was more attractive than rotten beef liver. Volatiles from the two livers were collected using solid phase microextraction. Significantly different volatile profiles were detected from the rotten livers of beef and chicken. Electroantennography (EAG) was performed to determine antennal responses to chemicals released from the most attractive chicken liver that are candidate oviposition attractants. Seven compounds from rotten chicken liver elicited significant EAG responses from antennae of gravid females. Oviposition assays showed that the 7-component blend stimulated gravid females to lay significantly more eggs than the other combinations tested. This 7-component blend may have potential for use in monitoring and sampling populations of secondary screwworm and their associated disease epidemiology.

Contact and fumigant toxicity of a botanical-based feeding deterrent of the stable fly, Stomoxys calcitrans (Diptera: Muscidae).

The stable fly, Stomoxys calcitrans (L.), has been considered one of the most serious biting flies of confined and pastured livestock. The economic losses caused by the stable fly to the cattle industry in the United States exceed $2 billion annually. Current practices for managing stable flies using insecticides provide only marginal control. Insecticide resistance has also been recently reported in stable flies. The present study reports the use of plant-based insecticides, for example, essential oils, as alternatives for managing this fly pest. The toxicity of several plant essential oils and selected ingredient compounds was evaluated by contact and fumigant toxicity bioassays. Catnip oil (20 mg dosage) showed the highest toxicity against stable flies, the shortest knock-down time (∼7 min), and the quickest lethal time (∼19 min). Toxicity levels similar to catnip oil were found among three insect repellent compounds (N,N-diethyl-3-methylbenzamide, 2-methylpiperidinyl-3-cyclohexene-1-carboxamide, (1S,2'S)-2-methylpiperidinyl-3-cyclohexene-1-carboxamide). No differences in knock-down and lethal times were found among the catnip oil and its two active ingredient compounds. Similar stable fly mortality was observed using a 20 mg dose of catnip oil in a modified K&D system and a fumigant jar. When catnip oil was topically applied to stable flies, the least lethal dose was 12.5 µg/fly, and a 50 µg/fly dose resulted in 100% mortality. The blood-feeding behavior of stable flies was also negatively affected by the topical application of catnip oil, and the effect was dose-dependent. This study demonstrated that catnip oil has both contact and fumigant toxicity against the stable fly and thus has the potential as an alternative for stable fly control.