Efficacy of entomopathogenic nematodes (Rhabditida: Steinernematidae and Heterorhabditidae) against the chive gnat, Bradysia odoriphaga

Chive gnat, Bradysia odoriphaga Yang & Zhang (Diptera: Sciaridae), is the most serious pest of Chinese chive, Allium tuberosum. The present study aimed at determining the biocontrol potential of different indigenous entomopathogenic nematode (EPN) isolates for the management of chive gnat in China. The virulence of 145 EPN isolates belonging to 13 species against B. odoriphaga was evaluated in the laboratory, and then the most promising isolates (Steinernema ceratophorum HQA-87; S. hebeiense JY-82; S. feltiae JY-90, JY-17; S. litorale HXY-68; Heterorhabditis indica ZZ-68; H. bacteriophora NY-63, HQ-94; and H. megidis LFS-10) were selected for further experiments. The mortality of fourth instar B. odoriphaga was significantly affected by nematode isolates and concentrations of infective juveniles (IJ). Third and fourth instars of B. odoriphaga were generally more susceptible to the nematodes than first and second instars and pupae. Pot experiments showed no differences in B. odoriphaga population reduction at 50 and 75 IJ/cm² of different isolates; the tested isolates caused a 78–94 % reduction of the chive gnat population at an application rate of 75 IJ/cm². In a field experiment, S. feltiae JY-90 generated the strongest pest suppression 14 days after EPN application, whereas after 28 days pest densities in the plots treated with S. feltiae JY-17 and S. hebeiense JY-82 were similar to those in plots treated with phoxim and yielded significant reductions of the B. odoriphaga populations. Our findings indicate that EPN may have good potential for use in the integrated management of B. odoriphaga populations in Chinese chive.     

Populations of adult fungus gnats and shore flies in British Columbia container nurseries as related to nursery environment,and incidence of fungi on the insects

Adult fungus gnat and shore fly populations were monitored in four container nurseries near Victoria, British Columbia. In general, populations of both insects were larger in summer than in winter. Also, both insects were more abundant in the nursery with a plastic-covered, soil floor, which favored moisture accumulation and build up of algae, liverworts and mosses, than in nurseries with other types of floors such as cement. Results of fungus isolations revealed that gnats and flies both harbor the seedling pathogens Botrytis cinerea and species of Fusarium and Phoma, plus several non-pathogenic fungi. The results are discussed in relation to nursery sanitation practices, their effects on gnat and fly populations, and some possible roles of these insects in seedling disease epidemiology.     

Empirical models for predicting the production of wild mushrooms in Scots pine (Pinus sylvestris L.) forests in the Central Pyrenees

Mushroom picking has become a widespread autumn recreational activity in the Central Pyrenees and other regions of Spain. Predictive models that relate mushroom production or fungal species richness with forest stand and site characteristics are not available. This study used mushroom production data from 24 Scots pine plots over 3 years to develop a predictive model that could facilitate forest management decisions when comparing silvicultural options in terms of mushroom production. Mixed modelling was used to model the dependence of mushroom production on stand and site factors. The results showed that productions were greatest when stand basal area was approximately 20 m² ha^?1. Increasing elevation and northern aspect increased total mushroom production as well as the production of edible and marketed mushrooms. Increasing slope decreased productions. Marketed Lactarius spp., the most important group collected in the region, showed similar relationships. The annual variation in mushroom production correlated with autumn rainfall. Mushroom species richness was highest when the total production was highest.     

Antibacterial activity of Nepalese wild mushrooms against <Emphasis Type="Italic">Staphylococcus aureus</Emphasis> and <Emphasis Type="Italic">Propionibacterium acnes</Emphasis>

The present study aims to reveal the antibacterial potential of the wild mushrooms of Nepal. Despite the recognition of the medicinal potential of the natural resources in this country, a systematic study on the bioactivities of the wild mushrooms is still lacking. Therefore, in an attempt to fill this gap, ethanol extracts of 90 Nepalese wild mushroom samples were tested for antibacterial activity against Staphylococcus aureus and Propionibacterium acnes. Staphylococcus aureus was comparatively more susceptible with Inonotus clemensiae exhibiting the least minimum bactericidal concentration (MBC) of 100 μg/mL. The major compound in I. clemensiae was identified to be hispidin using high resolution liquid chromatography–electron spray ionization mass spectrometry (LC–ESI-MS) and nuclear magnetic resonance (NMR) analyses. Furthermore, the minimum inhibitory concentration (MIC) and MBC values of hispidin were determined to be 25 and 100 µg/mL for S. aureus and P. acnes, respectively. These findings show that the Nepalese wild mushrooms have the potential to be a novel addition to the functional ingredients industry due to their strong antibacterial potential.     

竹木屑主基质配比菌棒对香菇出菇效率及品质的影响

本文以香菇为试验对象,通过分析竹屑与杂木屑主基质配比菌棒与传统基质菌棒污染率、出菇产量、营养成分和产出效益的差异,筛选出香菇菌棒的最佳竹屑与杂木屑主基质配比(以下简称竹木基质菌棒),系统揭示竹加工剩余物在食用菌栽培利用中的可行性,旨在为竹材资源高效利用提供新的途径.结果表明:3种竹木基质菌棒总污染率显著高于对照(P=0...     

Inversion relationship between action threshold and economic/aesthetic injury level for the control of urban and quarantine pests

Traditional agricultural pest control IPM theory claims that the action threshold (AT) is lower than the economic (EIL) or aesthetic injury level (AIL). Urban and quarantine pests are tolerated at the zero or near-zero population level. In the cases where responsive pest control strategies are used instead of preventive ones, inherently AT should be non-zero and higher than EIL/AIL. The constraints of the implementation of preventive treatment (= zero AT) for some urban pest problems requiring the zero EIL/AIL are discussed.     

Wood decaying properties of the termite mushroom <Emphasis Type="Italic">Termitomyces eurrhizus</Emphasis>

Four strains of the termite mushroom Termitomyces eurrhizus collected in Japan were surveyed for their wood decaying properties in three softwood and two hardwood species, in comparison with the white-rot fungus Trametes versicolor and the brown-rot fungus Fomitopsis palustris. All strains of T. eurrhizus degraded only the surfaces of the wood samples, and differences in mass-loss rates between heartwood and sapwood were generally not significant. Higher mass-loss rates were generally obtained in softwood than in hardwood. The results of chemical analyses of decayed wood samples indicated that T. eurrhizus does not have high lignin-degradation ability, even though it is categorized as a white-rot fungus. These results clearly suggest the unique physiological characteristics of T. eurrhizus.     

Chemical constituents from the rice fermented with the edible mushroom Pleurotus eryngii and their quinone oxidoreductase 1 inducing effect

The fruiting bodies or mycelia of mushrooms have been used as food and food-flavoring material for centuries due to their nutritional and medicinal values and the diversity of their bioactive components. The present research was the first to study the chemical components in rice fermented with the edible mushroom Pleurotus eryngii and the quinone oxidoreductase 1 inducing effect of these compounds. Through chemical investigation, one new compound, ((6S,7S)-6,7-dihydroxy-6-methyl-2-(3-methylbutanoyl)-4,5,6,7-tetrahydrobenzofuran-3-yl)methyl acetate (1) and eight known compounds (2–9) were isolated from the P. eryngii-fermented rice. All of these compounds were isolated from rice fermented with the edible mushroom P. eryngii for the first time. Their structures were elucidated by MS and NMR data analyses. Alternariol-5-O-methyl ether (2) showed strong quinone oxidoreductase 1 inducing effect with an IR value of 2.58 at the concentration of 20 μg/ml. The content of adenosine (8) in the fermented rice (175.64 μg/g) is much higher than that of non-fermented rice (14.38 μg/g).     

Efficacy of nine insecticides against shoot and fruit borer, <Emphasis Type="Italic">Leucinodes orbonalis</Emphasis> Guenee (Lepidoptera: Pyralidae) in eggplant

Shoot and fruit borer, Leucinodes orbonalis Guenee, is a serious pest of eggplant (Solanum melongena L.). Management practices of this obnoxious pest are limited to frequent spray of chemical insecticides. Due to increasing levels of resistance of L. orbonalis to different insecticides there is an urgent need to test new chemicals. In this study, nine insecticides such as azadirachtin 0.03EC, abamectin 1.8EC, flubendiamide 24WG, chlorpyriphos 20EC, cartap 50SP, carbosulfan 20EC, thiodicarb 75WP, cypermethrin 10EC, and lambdacyhalothrin 2.5EC belonging to different chemical groups were tested against eggplant shoot and fruit borer in laboratory and field. In laboratory trial, carbosulfan and flubendiamide showed the highest toxicity against fourth instar larvae of L. orbonalis after 24 and 48 h of exposure, respectively. In field trials, they reduced more than 80% shoot and fruit infestation in winter, and 80% shoot and 70% fruit infestation in summer over control. Carbosulfan protected the highest amount of healthy fruit yield in both cropping seasons. Flubendiamide also showed the similar efficacy. Cartap and thiodicarb were moderately effective in both the seasons. Efficacy of cypermethrin and abamectin was moderate in winter but low in summer. Lambdacyhalothrin and chlorpyriphos although reduced shoot and fruit infestation of eggplant and protected higher yield as compared to control, their effectiveness was not satisfactory. The performance of azadirachtin against the pest both in the laboratory and field trials was the poorest while that of carbosulfan and flubendiamide was the best. Thus, it is suggested that carbosulfan and flubendiamide may be used for the control of L. orbonalis in eggplant.     

Bait station preferences in two Macrotermes species

Baiting is considered to be a relatively environmentally benign termite control method; however, all commercial baiting systems are designed for species in the Rhinotermitidae and are used primarily in temperate countries. Fungus-growing termites in the Macrotermitidae can be important pests in tropical countries; they can be difficult to control using all available methods, and there are no baiting systems designed for them. We tested bait station size, an important component of bait station design, against two Macrotermes species in Singapore. Macrotermes gilvus recruited to small stations (0.35 L) very poorly and medium stations (3.6 L) poorly (both similar in size to various commercial stations), but they recruited to large stations (11.5 L) well. Macrotermes carbonarius followed a similar pattern but recruited to fewer stations overall. In the occupied stations, M. gilvus ate the bait wood, sometimes creating a fungus garden inside the stations, and brought little soil into the stations. In comparison, M. carbonarius ate no wood at all, but filled stations with soil. There was significantly less leaf litter around M. carbonarius mounds compared with M. gilvus mounds, although there were no obvious differences in habitat, which suggested that M. carbonarius eats leaf litter only and is not a pest species. Our study shows that stations much larger than current commercial options may provide a useful means for controlling pest wood-eating, fungus-growing termites in tropical countries.     

Methodology for determining susceptibility of rough rice to Rhyzopertha dominica and Sitotroga cerealella

Varieties of rough rice, Oryzae sativa (L.), were obtained from different sources in the south-central United States and evaluated for susceptibility to the lesser grain borer, Rhyzopertha dominica (Fab.), and the Angoumois grain moth, Sitotroga cerealella (Olivier), in laboratory studies. Adult R. dominica were fed on the rice varieties for 2 weeks, removed, and assessed for progeny production after an additional 6 weeks. Sitotroga cerealella susceptibility was evaluated by exposing two mating pairs of moths on a particular variety until the adults died. Rhyzopertha dominica parental survival, progeny production, and feeding damage by parental and progeny adults were variable, with survival ranging from 19.4 to 95 %. Rhyzopertha dominica parental feeding damage, progeny production, and progeny feeding damage were all correlated (r = 0.35–0.97, P < 0.001). Parental feeding of R. dominica provided access for neonate larvae to infest the rice hull. All rice varieties supported development of S. cerealella, and the variety Vista, which did not support growth of R. dominica, was one of the most susceptible varieties to S. cerealella. Progeny production of both species was generally correlated, but we observed only two instances of specific correlation for any rice variety. Results show that differences in variety susceptibility to stored product insects and differential susceptibility among species are important factors to consider when developing insect pest management programs for stored rice.     

A decade of successfull control of pine caterpillar,Dendrolimus punctatus walker (lepidoptera: Lasiocampidae), by microbial agents

Dendrolimus punctatus Walker has been one of the most serious pests of the pine trees Pinus luchuensis, P. elliottii and P. massoniana in northern Taiwan. It develops three generations each year. A combination of locally isolated species of fungus (Isaria farinosa), Bacillus thuringiensis, and a cytoplasmic polyhedrosis virus (CPV) isolated from D. spectabilis Butler in Japan was used to control the pest in different plantations during 1966–1971. The I. farinosa in combination with B. thuringiensis was applied for the first generation larvae (October–March) when it was cool and wet, and temperature and humidity were most suitable for the fungus. CPV and B. thuringiensis were applied in the second (May–June) or third generation (July–August) when conditions were favourable for the development of the virus, Since the applications, yearly observations have been made, and there was no occurrence of the pest until 1982, when outbreaks were seen in some of the plantations, and again in 1983. It is believed that the successful control was due to the microbial agents, and that their effectiveness had lasted for some 10–12 years.     

榆黄蘑高产栽培技术

本文介绍了榆黄蘑生长环境及栽培方法、母种制作、季节选择、配料装袋及灭菌、接种、发菌管理、出菇管理、采摘及后期管理、病虫害防治等高产栽培技术。     

Monitoring the appearance and possibility for prevention of the apple sawfly in Croatia

The apple sawfly Hoplocampa testudinea Klug has recently become a widespread pest in Croatian apple orchards. It causes severe damage in the blooming period due to the fact that infested fruit fall off. This article shows results collected over three years of field research on trap catches of sawflies, the period of laying eggs, the appearance of larvae and detection of damage. In the climate of northwestern Croatia, adult sawfly appear in April during the blooming period of the early apple variety of Idared. By monitoring temperatures from January 1, adults were detected when the thermal constant reached 210 day-degrees. Our observations showed that the larvae emerged when the sum of thermal constants reached ca. 110 day-degrees. The investigation of effective control strategies with insecticides showed high efficacy of thiametoxam (Actara), imidacloprid (Confidor), thiacloprid (Calypso) and betacyfluthrin + oxydemeton-methyl (Enduro) and lower efficacy of phosalone (Zolone), chlorpyrifos-methyl (Reldan), and lambda cyhalothrin (Karate).     

Statistical modelling of wildwood mushroom abundance

Abstract

This study analysed the relationship between weather conditions and the amount of wildwood mushrooms. A model of this relationship may be used to predict the amount of mushrooms with an elevated level of radionuclides that are available to domestic animals feeding outside during the summer and autumn months in Norway. Data on mushroom abundance were collected through a web application run by the Norwegian Mushroom Association. The data were coupled with meteorological data. Through linear regression analysis, it was found that average local cloud cover 5–3 weeks before the observation was the most important variable for explaining mushroom abundance at a given time and place. When controlling for cloud cover, weather variables covering rainfall, temperature, air humidity and wind speed had only marginal explanatory value. Of these, only rainfall and wind speed led to a significant (but small) improvement in the model. There was substantial unexplained residual variance in the model (R ²=0.23), but data analysis from identical locations and periods indicated that this was due mainly to variability in the response variable.     

Effective biological control of an invasive mealybug pest enhances root yield in cassava

Insects provide critical ecosystem services to humanity, including biological control of pests. Particularly for invasive pests, biological control constitutes an environmentally sound and cost-effective management option. Following its 2008 invasion of Southeast Asia, biological control was implemented against the cassava mealybug Phenacoccus manihoti (Hemiptera: Pseudococcidae) through the introduction and subsequent release of the host-specific parasitoid Anagyrus lopezi (Hymenoptera: Encyrtidae) in Thailand. In this study, we quantify yield benefits of mealybug biological control in Thailand’s cassava crop by using two different types of manipulative field trials: i.e., ‘physical exclusion’ cage trials and field-level ‘chemical exclusion’ assays. In cage trials with two popular cassava varieties, root yield and total dry matter (or ‘biological yield’) were a respective 4.0–4.2 times and 3.5–3.9 times higher in the presence of biological control. Extrapolating results from cage trials, biological control thus ensured an approximate yield gain of 5.3–10.0 T/ha for either variety. Under chemical exclusion trials, P. manihoti populations attained levels of 3266?±?1021 cumulative mealybug-days (CMD) over a 10-month time period, and no longer impact yields. Moreover, under effective P. manihoti control, both root yield and biological yield increased with season-long CMD measures, and pest management interventions-including insecticide sprays-led to notable reductions in yield. This study is the first to show how biological control effectively downgrades the globally invasive P. manihoti to non-economic status and restores yields in Thailand’s cassava crop. Our work emphasizes the economic value of biological control, reveals how current P. manihoti populations do not necessarily cause yield penalties, and underlines the central importance of nature-based approaches in intensifying global agricultural production.     

Characterization of antibiosis to the redbanded stink bug Piezodorus guildinii (Hemiptera: Pentatomidae) in soybean entries

Stink bugs are among the major pests of soybean [Glycine max (L.) Merrill] worldwide. Piezodorus guildinii [Westwood] (Hemiptera: Pentatomidae) is one of the predominant pest species, causing more severe damage in many regions than other stink bugs. Its attack reduces yield and quality of the beans. Plant resistance is a valuable strategy in integrated pest management that can reduce insect populations below economic injury level. Here, we report the resistance of 17 soybean entries to P. guildinii. PI 229358, PI 274454, L1-1-01, “IAC 19,” PI 171451, PI 227687, “IAC 100,” IAC 78-2318, PI 274453, and IAC 74-2832 caused high nymphal mortality (greater than 90 %), indicating the expression of antibiosis. “IAC 100,” IAC 74-2832, PI 274453, and “IAC 24” also increased the length of the nymphal stage of P. guildinii, showing the same mechanism of resistance. Our findings may be useful for breeding programs that focus on the resistance of soybeans to insects.     

Analyses of the genetic diversity of matsutake isolates collected from different ecological environments in Asia

Matsutake mushrooms are able to grow in two kinds of ecological environments: coniferous forests and broadleaf forests. Japanese matsutake is a form of the matsutake mushroom that mainly appears in coniferous forests in the mid-latitude regions of Asia. In contrast, matsutake from Yunnan and Sichuan Provinces of China grows in broadleaf forests in low-latitude regions. The taxonomic relationship and the genetic distance between these two types of matsutake remain unclear. Here, we compared the random amplification of polymorphic DNA (RAPD) data and the sequences of the internal transcribed spacer (ITS) region and of variable domains V4, V6, and V9 of mitochondrial small subunit ribosomal DNA (mt SSU rDNA) to determine the genetic differences of Tricholoma matsutake strains collected from different ecological and geographic environments in Asia. We found few differences in the sequences of the variable domains, implying that all matsutake strains are the same biological species regardless of their host specificity and geographical differences. This conclusion is also supported by the sequences of the ITS region. On the other hand, RAPD analysis revealed that the matsutake mushrooms collected from different ecological environments have genetic differences and represent distinct varieties.     

The smell and odorous components of dried shiitake mushroom, Lentinula edodes III: substances that increase the odorous compound content

This study formed part of an effort to improve the quality of dried shiitake mushroom [Lentinula edodes (Berk.) Pegler], in accordance with consumer preferences, and deals with the search for substances that increase the odorous component content. From analysis of sulfur and sulfur-containing substances in the culture substrate, rice bran was found to be the main source of sulfur, and 75% of this was present as cysteine and methionine. The sulfur-containing substances were added to a sawdust medium containing only rice bran and sawdust as a substrate; shiitake mushrooms were cultivated in the medium, the fruiting bodies were dried, and the 1,2,4-trithiolane content in the fruiting bodies was measured as an indicator of the odorous compounds. Of the sulfur-containing substances, those that increased odorous compounds the most were cysteine and methionine. The efficiency of cysteine in this regard was higher than that of methionine. It was also noted that the amount of glutamic acid increased the odorous compounds in combination with cysteine and methionine. Furthermore, the addition of both amino acids and glutamic acid had no negative effect on the yield. These results showed that it is possible to produce dried shiitake mushrooms with a smell suitable for particular consumer preferences.     

锈色粒肩天牛的防治试验

锈色粒肩天牛是国槐毁灭性害虫，成虫在树体外活动，是防治的最佳时期。本次防治试验采用绿色威雷，高氯氰可湿性微胶囊剂和吡虫啉可湿性微胶囊剂，这些药剂对锈色粒肩天牛具有击倒快，药效高，持续期长的优点。30d后通过爬行，取食，毒杀效果仍达90％以上；并对卵的防治效果也达85％以上。