bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficacy and persistence of Indian meal moth granulovirus applied to nuts.
Authors: Vail P. V. , Tebbets J. S. , Hoffmann D. F.
Published: November 2017

The Indian meal moth (IMM, Plodia interpunctella) granulovirus (GV) was first isolated and characterized in 1968 by Arnott and Smith. As a group, the Baculoviridae are considered to be safe. A number have been registered worldwide for control of production pests. In the late 1960s, interest increased in the use of microbial agents to control stored-product pests in durable commodities. Numerous studies have demonstrated efficacy against IMM infestations in raisins, almonds, and walnuts. A production/formulation method for IMM-GV was later patented. The GV was combined with controlled atmospheres for initial disinfestation of IMM populations in unshelled walnuts followed by treatment with the GV for long-term storage. The IMM-GV provided excellent protection of walnuts even with severe IMM pressure for a period of four months. Similar tests were conducted with almonds. After the tests described above were complete, we determined the persistence/efficacy of GV on treated nuts through a period of two years. Immediately after the initial 3-4 months, treated and control walnuts and almonds were frozen to kill any IMM remaining in the commodities. Thereafter, walnuts or almonds were removed and placed in sealed storage at 26.7°C. Samples were removed bimonthly, placed in 3.8-litre jars, infested with approximately 1000 IMM eggs, and incubated at 26.7°C for six weeks. The tests were replicated twice in time. Following incubation the nuts were observed for numbers of IMM adults and damage (pin hole, moderate, and severe). Although efficacy was determined, the primary objective of this study was to determine persistence. Results of these studies showed that IMM-GV would persist for at least two years. Survival and damage to walnuts exceeded that of almonds. Infestation rates used in these tests are unreasonably high and bias the data towards more damage than would likely occur commercially. Our grading procedures are also likely to be more rigid than would be used commercially. The virus is now registered with the United States Environmental Protection Agency and California Environmental Protection Agency.
Optimal clutch size and oviposition strategy for the maize weevil, Sitophilus zeamais.
Authors: Danho M. , Haubruge E.
Published: November 2017

Facing an oviposition host, a female insect must make at least two decisions: (1) where to lay her eggs and (2) how many eggs to lay in each site. The answers to these questions could explain the oviposition strategy, which determines fitness of offspring and growth rate in the population. Experiments were carried out to investigate the egg-laying behaviour of the maize weevil, S. zeamais. The selection of the oviposition site by the maize weevil and the effect of the presence of egg plugs on oviposition were studied. The distribution of the number of eggs per grain shows a contagious pattern due to a tendency of females to lay more than one egg on the same grains. The behaviour is independent of grain size and grain availability. No relationship was noted between the number of eggs laid on the grains and the size of the adults resulting from the offspring. Consequently, the possibility that this behaviour reflects an adaptive strategy of S. zeamais is discussed.
Traditional cereal storage and insect pests in some villages of southern Chad.
Authors: Trematerra P. , Gentile P. , Djikoloum T.
Published: November 2017

Results of cognitive surveys carried out on postharvest aspects of cereal storage and insect pest infestations were reported at farm/village level in 10 villages (Bebanassa, Beboumbura, Bekila, Bekoura, Belama, Betedje, Bongmara, Doholo, Gore, and Polo) of Southern Chad. In this area, millet, sorghum, maize, and pearl millet are among the most important staple foods. Traditional methods of grain storage are applied in an economy essentially oriented towards survival and self-sufficiency. Open timber platforms are the main facilities used for temporary storage. The most common facilities for long-term storage are mud or clay silos, jute or polypropylene sacks, cribs made of plant materials exclusively, and clay jars and hats constructed of wood and straw or of earth bricks. Gourds and calabashes are usually used for domestic storage of products in small amounts. According to information received from the farmers regarding postharvest losses of cereals, 70-80% of the harvest is lost after 8-9 months of storage. The most common storage problems mentioned by the villagers are insect pest infestations and rodent activity. Local people rely on indigenous pest management approaches, which include the use of inert materials and botanicals for the control of storage pests. Stored grains revealed infestations of many insect pests. In the samples of cereals taken to the laboratory, Cryptolestes ferrugineus, Cryptolestes ugandae, Palorus ratzeburgi, Rhyzopertha dominica, Sitophilus oryzae, Tribolium castaneum, and T. confusum were found most frequently. Traditional storage methods carried out by farmers are well anchored in the culture of local people; nevertheless, they seem to be ineffective in containing the heavy losses caused by pest infestations.
Insect pests in hulled wheat warehouses of central-southern Italy and field occurrence of Sitotroga cerealella (Olivier).
Authors: Trematerra P. , Gentile P.
Published: November 2017

Results of studies carried out from 1998 to 2002 on stored insect pests of hulled wheat (Triticum dicoccum, T. monococcum, and T. spelta) in traditional crop areas of Central-Southern Italy (Molise and Basilicata regions) were reported. Surveys were carried out in about 50 warehouses of small farms and food factories. Stored hulled wheat revealed infestations of about 20 insect pests. Trogium pulsatorium, Ephestia elutella, Plodia interpunctella, Sitotroga cerealella, Cryptolestes ferrugineus, Oryzaephilus surinamensis, Rhyzopertha dominica, Sitophilus granarius, Sitophilus oryzae, and Tribolium castaneum were most frequently found. Among these species the ecology of S. cerealella has been studied. Using pheromone traps (delta types) baited with 1 mg of Z7E11-16Ac, observations of adult flights in fields and in warehouses of hulled wheat were carried out. According to our research, infestations of the Angoumois grain moth can occur during both preharvest and postharvest storage. Results obtained in the fields studied showed various levels of infestation with different population abundances. The highest numbers of S. cerealella males were trapped in two fields located in the same area of the Molise region, where there are many traditional warehouses; the presence of adult males was also recorded after harvesting, until the beginning of September. In the warehouses containing the hulled wheat harvested in this area, males of Angoumois grain moths were also collected until autumn and again in the following spring. S. cerealella activity suggests adult dispersal from the warehouses to hulled wheat fields during the Summer season.
Prey preference of the predatory mite Blattisocius tarsalis (Acari: Ascidae).
Authors: Riudavets J. , Quero R.
Published: November 2017

The preferences of the polyphagous predatory mite B. tarsalis were investigated for several pests of stored products. In the laboratory, B. tarsalis was able to consume a wide range of species including Acaridae, Lepidoptera, Coleoptera and Psocoptera. In no-choice conditions, B. tarsalis consumed similar numbers of eggs of Plodia interpunctella, Ephestia kuehniella, Lasioderma serricorne, and Tribolium confusum. In choice experiments, B. tarsalis showed a clear preference for eggs of P. interpunctella over those of T. confusum and E. kuehniella. No significant differences were found for the other prey species combinations.
Investigations on the biological control of Tineola bisselliella (Lepidoptera: Tineidae) with Trichogramma species (Hymenoptera: Trichogrammatidae).
Authors: Zimmermann O. , Schöller M. , Prozell S.
Published: November 2017

The common clothes moth T. bisselliella is among the most important pests in textile products containing wool and fur, e.g. clothes collections in theatres and museums as well as clothes and carpets in private homes. Biological control of T. bisselliella may be possible by the release of Trichogramma egg parasitoids. Among 30 species, Trichogramma piceum was the most promising candidate. The results of host acceptance and preference tube tests with single parasitoid females were consistent. In two experiments conducted, the performance of T. piceum was better than all other Trichogramma species tested. The species were selected from a collection of Trichogramma parasitoids at the Institute for Biological Control in Darmstadt, Germany and from a German supplier of beneficials. As there are suitable methods for Trichogramma mass production and release, practical tests will follow to transfer the results from laboratory to practical storage pest control.
Five years of biological control of stored-product moths in Germany.
Authors: Prozell S. , Schöller M.
Published: November 2017

The application of macroorganisms for the biological control of stored product pests in Germany is reviewed. In bakeries and mills, the Mediterranean flour moth Ephestia kuehniella is the major pest moth. The egg parasitoid Trichogramma evanescens and the larval parasitoid Habrobracon hebetor [Bracon hebetor] are released 12 months. In the food processing industry, the wholesale trade and the retail trade, the Indian meal moth Plodia interpunctella is the major pest moth. Due to the diapause of this species, the same parasitoids are released for eight months. Empty rooms were treated to control residual populations. Additional information on control actions in herb stores, seed storage and private households is given. The cost of biological control is estimated.
Role of insects in the propagation of mycotoxigenic fungi in stores in Bénin.
Authors: Hell K. , Lamboni Y. , Cardwell K.
Published: November 2017

With their movement, maize storage pests transmit moulds harmful to human and animal health. The aim of the present work was to study the immigration and the dynamics of storage pests in traditional African maize granaries during six months of storage, and the fungal spectrum associated with these insects. In the field, maize ears were protected with gauze just after pollination. After harvest, they were stored, with non-protected ears used as the control. Thirty ears were sampled monthly from September 2000 to March 2001. The granaries were wrapped with a plastic wire netting impregnated with neutral glue (Tanglefoot) to capture pests immigrating towards stored maize ears. Eight different insect species were identified: Prostephanus truncatus, Sitophilus zeamais, Cathartus quadricollis, Carpophilus spp., Tribolium spp., Palorus spp., Gnatocerus spp. and Cryptolestes ferrugineus. During the six months of storage, P. truncatus was not observed on maize protected in the field, while after three months of storage non-protected maize was infested. Sitophilus numbers on protected maize ears were lower than on non-protected maize ears. Only Cathartus was more abundant than P. truncatus, peaking after three months of storage. Nine fungal species were associated with the storage insects. On non-protected ears the genus Fusarium (36.05%) was most frequently identified, followed by Penicillium (23.50%), Rhizoctonia (5.65%) and Aspergillus (3.95%). On protected ears, Rhizoctonia was most frequent (16.76%), followed by Fusarium (16.62%), Penicillium (8.24%) and Aspergillus (2.33%). The toxigenic species encountered were A. flavus, A. parasiticus and F. verticillioides. Cathartus appeared to carry more fungi towards the store, mainly Penicillium (51.47%), Aspergillus (46.56%) and Fusarium (32.01%). The second most important vector was Sitophilus. Storage pests, in particular Cathartus and Sitophilus, play an important role in the contamination of foods with moulds, especially those that produce toxins.
Method for rearing Oryzaephilus surinamensis (L.) (Coleoptera: Silvanidae), a pest of stored wheat, in the laboratory.
Authors: Beckel H. , Lorini I. , Lazzari S. M. N.
Published: November 2017

O. surinamensis, the sawtoothed grain beetle, is considered a secondary pest of stored grain because it is unable to attack undamaged kernels. However, mechanized harvesting of grain fractures kernels, allowing damage by this species and, thus, the beetle may be regarded as a primary grain pest. In Brazil, O. surinamensis has been found in almost all storage facilities. The aim of this work was to develop a method for laboratory production of the species using wheat grain to produce high quality specimens for research experiments, such as chemical resistance investigations. Adult insects were collected in grain storage facilities and brought to the Entomology Laboratory of Embrapa Trigo in Rio Grande do Sul, Brazil, and the experiment was set up rearing the insects on five diets of differently milled wheat grain, replicated four times. The adults were sieved from the culture and left for 10 days to lay eggs in glass jars filled with each medium, which were kept at 25±5°C and 65±5% relative humidity. After this period, the medium was sieved to remove all adults. The number of eggs, larvae, and pupae were counted at five-day intervals, up to the following adult generation. The results showed that a diet of grade-20 milled wheat produced the highest quantity and best quality of offspring. With this diet, it was also observed that it is possible to get 89.0% of eggs at day 5, 30.5% of larvae at day 10, 43.0% of pupae at day 30 and 63.4% of adults at day 46.
Near-infrared transmittance spectroscopy for detection of insects and mites in grain.
Authors: Hansen L. S. , Åberg L. , Kristensen M. , Sandgren M.
Published: November 2017

Near-infrared transmittance spectroscopy (NIT) is used as a rapid analysis method to determine protein and moisture contents in grain arriving at commercial elevators and mills. There is great interest in expanding this technique to include mycotoxins and pests. A pilot project has studied the possibilities of a commercially available instrument (InfratecTM, Foss Tecator) that applies NIT. The following hygienic parameters were included: ergosterol (a component of fungal cell membranes); the mycotoxin deoxynivalenol; and two pest species, the granary weevil Sitophilus granarius and the grain mite Lepidoglyphus destructor. For S. granarius, the detection limit was not low enough for the method to be of practical interest. The results with mites were more encouraging; a good correlation between mite density and analysis result was found. However, further investigations are necessary to clarify performance at low mite densities as well as the lower detection limit. The work with mites and mycotoxins is being continued in a new, three-year project.
Development and validation of a simple heat-accumulation model for predicting mortality of first instars of Tribolium castaneum (Herbst) exposed to elevated temperatures.
Authors: Subramanyam B. , Flinn P. W. , Mahroof R.
Published: November 2017

First instars of the red flour beetle, Tribolium castaneum, are more tolerant than eggs, older larval instars, pupae and adults to elevated temperatures (50-60°C) typically used during heat treatments. Therefore, heat treatments aimed at controlling first instars should eliminate all other stages. First instars of T. castaneum were exposed to four constant temperatures of 50, 54, 58 and 60°C to generate time-mortality relationships. About 157 of the 255 observations (62%) collected at the four temperatures were used for model development, and the remaining 98 observations (38%) were used for model validation. The temperature-time data were expressed in degree minutes above a base temperature. First-instar mortality at corresponding degree minutes above a certain base temperature was fitted to probit, logistic and complementary log-log (CLL) regression models. The base temperature for accumulating degree minutes was solved iteratively, and the temperature that gave the narrowest 95% confidence limits (CLs) around LT50 and LT99 values was chosen for accumulating degree minutes. The CLL model at a base temperature of 49.1°C gave the narrowest 95% CL around LT50 and LT99 values. At 49.1°C, the degree minutes (and associated 95% CLs) required to kill 50 and 99% of exposed first instars were 165.8 (148.8-180.4) and 395.2 (343.7-487.2), respectively. The CLL-based degree minute model underestimated mortality by 25%, but explained about 70% of the variation in observed mortality data. The ability of the degree minute model to accurately predict mortality of T. castaneum first instars during heat treatment of a food-processing facility still remains to be verified.
The ability of buried PCTM traps to detect stored-product mites in wheat.
Authors: Clarke P. G.
Published: November 2017

Mites are a major pest of stored grain in the UK. Recent interest in mite presence has been stimulated by the potential health effects of ingesting mites and their products and the development of resistance to organophosphate pesticides (Wildey, K.B., Prickett, A.J., MacNicoll, A., Thind, B.B., 1998, Proceedings of the Brighton Crop Conference-Pests and Diseases 1:503-510). Although mites are often present in stored products it is not known if mites pass from storage into finished food. Traps exist to monitor beetles in grain bulks and mites in empty stores, and manufacturing premises. It may be possible to use these to monitor mites in bulk-stored grain. An initial study compared the populations of the major UK mite pests (Acarus sp., Glycyphagus sp. and Tyrophagus sp.) in buried PC traps, probe traps and Mite Monitors with populations recovered from grain samples taken from the surface of a 100 tonne managed grain bulk. A second, laboratory-based, experiment assessed the ability of the buried PC trap to detect three major storage pest species: Acarus siro, Lepidoglyphus destructor and Tyrophagus longior. The ability of this trap was assessed against single and mixed species populations; it was also tested with Mite Monitor bait added to the trap. Results from the initial study showed that there were discrepancies between mite genera found in the grain samples and the traps. In the samples 44% of mites recovered were Acarus sp., 23% Glycyphagus sp. and 33% Tyrophagus sp. However, more than 75% of mites found in PC and probe traps were Acarus sp. and 55% of those found in Mite Monitors were Tyrophagus sp. Very few Glycyphagus sp. were found in traps. Similar proportions were found in the laboratory study. Buried PC traps contained more A. siro than L. destructor or T. longior when either single or mixed species populations (with equal numbers of the different species) were examined. When Mite Monitor bait was present the proportions of T. longior and A. siro in the traps were equal. The implications of these results on the use of traps to monitor mite populations in grain are discussed and it is concluded that, although currently existing traps may be suitable for monitoring mites in grain, more work is necessary to understand interspecies interactions and the relationship between trap catch and actual populations.
The effects of high-temperature drying on fragrant rice.
Authors: Moi YawGeok [Moi Y. G. L. ] , Srzednicki G. , Craske J.
Published: November 2017

The effects of high temperature drying on fragrant rice cv. Kyeema were studied. High moisture paddy was dried using two-stage drying process which involved a fluidized bed at high temperature reducing moisture content to 18% wet basis (w.b.), followed by shade drying with a further moisture reduction of 14% w.b. Drying air temperatures of 150, 125 and 100°C were trialled in the fluidized-bed drier. Likens-Nickerson simultaneous distillation-extraction technique was used to extract the volatile compounds from grains, and gas chromatography-mass spectrometry and gas chromatography were used to separate, identify, and quantify the volatile compounds extracted. Sixty-one volatile compounds were identified. These included 12 alcohols, 10 aldehydes, 9 ketones, 9 acids, 7 hydrocarbons, 3 heterocyclic and 8 miscellaneous compounds. An increase in drying temperatures led to the formation of new compounds, as well as losing other desirable volatiles. Quantitatively, aldehydes were the major class of volatile compounds found in Kyeema rice samples. The three different drying temperatures using the fluidized bed drier affected the flavour profile of Kyeema rice. The sensory results also showed that rice dried at 125°C had the most desirable flavour, which may be due to the presence of the newly formed volatile compounds identified in the rice sample.
Estimation of safe storage periods for malting barley using a model of heat production based on respiration experiments.
Authors: Jacobsen E. E. , Fleurat-Lessard F.
Published: November 2017

The respiration of grain is closely associated to heat production that mainly resulted from the combination of unfavourable storage conditions (temperature and moisture content (m.c.)). In addition, temperature and moisture content are the prime factors affecting the germinative capacity of malting barley. The possibility of describing the respiration of malting barley by way of a mathematical model based on these two measurable factors was investigated. The effects of temperature (range 10-39°C) and moisture content (range: 15-25% wet basis) (converted to water activity, Aw) on the respiration of barley was investigated experimentally. A mathematical model based on the two controlled variables was developed from the experimental data for the estimation of oxygen (O2) consumption and carbon dioxide (CO2) production. A general equation for O2 consumption (O2 cons) or CO2 production (CO2 prod) was: ln(respiration temperature)=a+b(Aw). This model showed highly significant correlation coefficients of 0.982 and 0.974 for O2 cons and CO2 prod, respectively. Oxygen consumption was converted into heat production using theoretical conversion factors. This second formula enabled the calculation of the rise of grain temperature to the limit of 35°C, which corresponded to the threshold for the deterioration of seed viability. It was then used to create another model, usable graphically or by computer, and enabling the assessment of the "safe storage life" of malting barley as dependent on moisture content and temperature.
An alternative approach to assessing pest problems in stored grain.
Authors: Wilkin R.
Published: November 2017

Conventional surveys of pest problems in stored grain can be expensive and time consuming. As an alternative, data were collected using the intake inspection records from five intervention grain stores and two maltings. The results were based on samples collected from incoming loads and other information that was gathered at the same time. Assessments based on about 200 000 tonnes of barley sold into intervention during a single storage season showed that less than 2.5% of the grain was rejected because of infestation. Almost half the grain delivered had received some form of chemical treatment before despatch to the store. Data on delivery of grain to two maltings were monitored over a 5-year period and showed that, although just below 3% of loads were rejected, less than 1% of rejections were caused by infestation. The implications of this approach to collecting information and the significance of the results are discussed.
Development of management options for the control of aflatoxin in maize in West Africa.
Authors: Hell K. , Fandohan P. , Cardwell K. F.
Published: November 2017

From 1999 till 2001, management strategies for the reduction of aflatoxin in maize were developed in participatory tests with farmers. After 6 months of storage, maize in bags contained more aflatoxin than maize in traditional farmers' stores. Harvesting maize late increased the risk of aflatoxin contamination. Sorting out damaged maize before storage significantly decreased the levels of aflatoxin in stored maize. All the management strategies were evaluated, and the economic benefit assessed against traditional farming practices. Fungal infection and insect infestation were measured and related to aflatoxin contamination. A technology package for the reduction of aflatoxin in maize will be developed for each agroecological zone in Bénin, comprising specific maize varieties, harvest timing, drying, sorting, insect control and storage technologies.
Sorption of carbonyl sulfide by stored products.
Authors: Weller G. L.
Published: November 2017

As a consequence of a search for an alternative to methyl bromide for the fumigation of stored products, carbonyl sulfide (COS) was patented for its fumigant properties. While the toxicity of this gas to insects is well documented, the behaviour of COS on commodities needed to be investigated. The sorption of COS by a diverse range of commodities - cereals (wheat, barley, oats, maize, rice and sorghum), pulses (field peas, red kidney beans, lupins, soyabeans, mung beans and chickpeas), oil seeds (rape, safflower, linola, fuzzy cottonseed and sunflower seeds), dried fruits (apricots, peaches, pears and sultanas), spices (chillies and cardamom), almonds, cocoa beans and coffee beans - has been assessed under a set of comparable conditions. Red kidney beans and sunflower seeds were highly sorptive and may not be suitable for fumigation with COS. The role of moisture content, age of commodity and history of previous fumigation with COS were investigated. Increasing moisture content increases the rate of sorption whereas increased storage time appears to reduce the rate of sorption, as does the number of times that a commodity has been previously fumigated with COS.
The effect of storage conditions on the quality of Australian canola (rapeseed), Brassica napus L.
Authors: Reuss R. , Cassells J.
Published: November 2017

In 2002-03, 1.6 million tonnes of rape (rapeseed) are expected to be harvested in Australia. Increased production of canola has resulted in more prolonged storage before end use or export. This paper examines the effect of storage conditions and storage period on the quality of two Australian rape cultivars. Samples of the cultivars Oscar and Pinnacle were conditioned to moisture contents of 6, 7 and 8% and stored at 20, 25 and 30°C for nine months. There were measurable differences between freshly harvested rape and stored rape. Changes were mostly dependent on the storage conditions, but differences between cultivars and the intake condition of the grain were also important. Generally, the most significant changes occurred at the highest moisture content (m.c.) and storage temperatures. Loss in germination energy reflected the intake quality of rape and storage at high temperatures and moderate m.c. Seed coat colour changes were an indicator of chemical changes during storage. Changes in the UV-visible spectra of rape oil, fatty acid composition, and NIR spectra were also influenced by storage parameters. Free fatty acid accumulation was the most useful indicator of potential storage-induced quality loss. Future work will include data on storage periods less than nine months and detailed analysis of chemical, biological, and chemometric data.
The technical foundation for precision stored-product-pest fumigation with ProFumeTM gas fumigant.
Authors: Schneider B. , Voglewede C. , Houtman B.
Published: November 2017

Dow AgroSciences is developing ProFume gas fumigant (99.8% sulfuryl fluoride) to control stored-product pests in milling, food-processing, and food-storage facilities. Sulfuryl fluoride has positive fumigant qualities, including: efficacy in controlling insect pests, a low boiling point, excellent penetration qualities, low reactivity potential, limited sorption, and rapid aeration. Effective dosages for all life stages can be obtained by varying concentration and exposure time. Lower dosages are necessary at higher temperatures due to the insects' increased metabolism. With some limitations, tolerances and maximum residue limits for sulfuryl fluoride and fluoride (the two terminal food residues of interest) will be established to support the fumigation of a wide variety of grains and tree nuts, along with processed foods. Taste and quality trial results indicate that dried fruit and tree nuts were not adversely affected by ProFume. Wheat kernel quality trials showed that ProFume exposure did not affect the nutritional characteristics and rheological properties of the milled fractions of hard red winter, soft red winter, and durum wheat kernels. Dow AgroSciences has developed the ProFume Fumiguide, a PC-based software program to calculate dosages specific to the pest and environmental conditions of each fumigation. Dow AgroSciences will administer a comprehensive ProFume fumigation training and stewardship programme emphasizing worker, bystander, and environmental safety. Country registrations are expected in the United States in 2002 and in the European Union in 2004.
Two decades of monitoring and managing phosphine resistance in Australia.
Authors: Collins P. J. , Emery R. N. , Wallbank B. E.
Published: November 2017

The Australian grain industry relies heavily on phosphine to meet domestic and international market demand for high-quality grain, free of insects. Phosphine usage has increased markedly over the past 10 years, because of market reluctance to accept chemical residues and resistance in target pests to grain protectants. The threat that insects may also develop resistance to phosphine led to resistance-monitoring projects being initiated across all cereal-growing regions of Australia. The rationale was that the industry needed to be proactive in developing strategies to combat resistance when it evolved, and required early warning of the development of resistance and a scientific assessment of its likely impact. With industry support, these projects have now amalgamated to form a national phosphine resistance monitoring and management programme. Insect population samples are collected from farms, grain merchants, mills and central storages, and tested for resistance. If the resistance is classified as significant, then action is taken to eradicate or control the strain and, where feasible, to prevent its further distribution. In addition, research is undertaken to fully characterize the resistance and to develop control options such as changes to fumigation concentrations and exposure periods. Although the three collaborating laboratories are widely spaced geographically, they maintain close links through data sharing on an Internet-accessible database. They share a common procedures manual, and the groups independently confirm diagnoses of significant resistance made in other laboratories. They also hold regular national workshops to benchmark their suite of bioassays and other techniques and report at least annually to the industry through various forums. The Australian approach is unique in that it has drawn together primary producers, bulk handlers, chemical companies, industry funding organizations and government research institutions from across the country to combat the national threat of phosphine resistance.
Securidaca longepidunculata (Fres.) as a control for stored product insect pests.
Authors: Jayasekara T. K. , Belmain S. R. , Stevenson P. C. , Hall D. R.
Published: November 2017

The plant Securidaca longipedunculata is known to have various ethnopharmacological and pesticidal properties, including its indigenous use by small-scale African farmers for stored product pest control. This paper reports the results of a study involving 4 stored-grain insect pest species, Sitophilus zeamais, Rhyzopertha dominica, Callosobruchus maculatus, and Prostephanus truncatus, which showed that the powdered root of Securidaca longipedunculata (collected from Tamale, Ghana) admixed with commodity at 0.5% w/w was effective at reducing the F1 emergence of all 4 species when compared with untreated commodity trials. A methanol extract of Securidaca longipedunculata roots sprayed on commodity at 0.1% w/w was equally effective at reducing F1 emergence compared with the control. Bioassay-guided fractionation of the methanol extract showed that the most polar compounds in the roots were responsible for the reduction of live adults in the F1 generation. The implications of these results are discussed in the context of isolating and characterizing biologically active compounds with a view to improving stored-product pest control by small-scale farmers in developing countries.
Study on the insecticidal effects of custard apple (Annona reticulata L.) and mindi (Melia azedarach L.) leaves against Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae).
Authors: Haryadi Y. , Yuniarti S.
Published: November 2017

The insecticidal properties of custard apple (A. reticulata) and mindi (M. azedarach) leaf powder were tested against maize weevil, S. zeamais. The experiment was conducted under laboratory conditions using oligidic diet in the form of artificial grains. To the diet, 10 levels (0.0 to 4.5% w/w) of the dry, powdered plant materials were added. Ten adults of unsexed S. zeamais aged 7-15 days were added to about 120 artificial grains in a closed but aerated plastic container. Each treatment was replicated 5 times. After 7 days of oviposition, the parent insects were removed and discarded. The grains were incubated under laboratory conditions and after about 3 weeks were examined for the emergence of progeny. The emerging progeny was removed and counted daily until there were no emergences for 5 consecutive days. The parameters observed were the number of progeny, the developmental period, and the developmental index. The results showed that the presence of the plant materials in the diet significantly reduced the number of progeny, prolonged the developmental period, and reduced the developmental index. Mindi leaf in particular, showed strongly insecticidal effects against S. zeamais. At 2.0% of the mindi leaf powder in the diet the numbers of progeny in all 5 replicates were reduced to zero.
Efficacy of pea protein and combinations of pea protein and wasps against stored-grain insects in large-scale tests.
Authors: Hou XingWei Hou XingWei , Fields P. , Flinn P. , Perez-Mendoza J. , Baker J.
Published: November 2017

Protein-enriched pea flour is toxic and repellent to three major stored grain pests, the rice weevil, Sitophilus oryzae, the red flour beetle, Tribolium castaneum and the rusty grain beetle, Cryptolestes ferrugineus. A unique and valuable aspect of the protein-enriched pea flour is that it is not toxic to several parasitoids that are associated with two of these insect pests. These parasitoids include Anisopteromalus calandrae, a parasitoid of S. oryzae, and Cephalonomia waterstoni, a parasitoid of C. ferrugineus. Two, large-scale tests, including one test in combination with the parasitoids, were conducted to evaluate the effectiveness of the pea flour as a grain protectant in Manitoba, Canada. A 2-month, 30-tonne-granary trial with barley was conducted in 6 bins, each filled with 11 tonnes of barley. Bins had full-floor aeration, hence insects could leave or enter the grain mass. Results showed that treating all the barley during loading with 0.1% of pea protein had a similar effect to treating the barley in only the top half of the granary with 0.5% of pea protein. Compared with control bins, the treatments with protein-enriched pea flour reduced the size of S. oryzae populations by more than 90%, and those of Cryptolestes ferrugineus and T. castaneum by more than 70%. A 5-month, 330-kg-barrel test with wheat was set up to test the effectiveness of the combination of protein-enriched pea flour with parasitoids against S. oryzae and C. ferrugineus. The parasitoids A. calandrae and C. waterstoni reduced the mean number of S. oryzae by about 70%, but the reduction was not significant because of high variability in the controls. Combinations of parasitoids and pea flour at 0.1% reduced the S. oryzae population by 99.8%. For unknown reasons, the populations of C. ferrugineus did not become established in the barrel tests. As a result, we could draw no conclusions concerning the effectiveness of the combination of parasitoids and protein-enriched pea flour against this major pest.
The effect of relative humidity on the efficacy of the diatomaceous earth Protect-ItTM against Liposcelis entomophila (Enderlein) (Psocoptera: Liposcelididae).
Authors: Cao Yang Cao Yang , Xia Lili Xia Lili , Zhang HuaiJun Zhang HuaiJun
Published: November 2017

This paper examines the effect of relative humidity (55, 65, 71 and 76% r.h.) on the efficacy of the diatomaceous earth Protect-It against Liposcelis entomophila adults. The diatomaceous earth was applied as a surface treatment at 0.3, 0.7, 1.0, and 3.0 g/m2. Insects were held at 25±1 °C for 1 to 8 days before mortality was assessed. As predicted, lower relative humidities, higher concentrations of diatomaceous earth or longer exposures increased mortality. At 55% r.h., 100% mortality occurred at all concentrations after 4-day exposure. At 65% r.h., the results were similar to those at 55% r.h. At 71% r.h., 100% mortality occurred only after 4 days at 3.0 g/m2, and after 6 days at 1 g/m2. At 76% r.h., 100% mortality was never obtained with the 8-day tests, although mortalities rose between 69 and 92%. We believe the diatomaceous earth would be useful to reduce populations of L. entomophila and other stored-grain insect pests in empty granaries and in the top and bottom layers of the grain.
Efficacy of heat treatments against the tobacco beetle Lasioderma serricorne F. (Col., Anobiidae) and the lesser grain borer Rhyzopertha dominica F. (Col., Bostrichidae).
Authors: Adler C.
Published: November 2017

All developmental stages and adults of the tobacco beetle L. serricorne and the lesser grain borer R. dominica were tested for their tolerance against heat treatments. Each age cohort, together with 10 mL of substrate, was exposed to 45, 50 and 55°C in preheated glass tubes in a water bath. At 45°C, pupae of the tested population of R. dominica proved more tolerant to heat treatments than L. serricorne, while at the higher temperatures, eggs of the tobacco beetle were most difficult to control. At 45°C, it took 40 h to control the tobacco beetle, but 100 h to control the lesser grain borer. At 50°C, exposure times of up to 280 minutes were not sufficient to control L. serricorne and R. dominica. At 55°C, first results seem to indicate that 40 minutes may be sufficient to control both species, but more data are needed to support this finding. The findings indicate that all life stages of critical species should be tested to determine effective heat treatment schedules.
Heat disinfestation of wheat in a continuous-flow spouted bed.
Authors: Rashid Qaisrani Rashid Qaisrani , Beckett S.
Published: November 2017

A continuous flow spouted bed with a draft tube was developed and tested for heat disinfestation of grain. Fifty tonnes of wheat naturally infested with mixed age populations of Rhyzopertha dominica, Cryptolestes ferrugineus and Liposcelis bostrychophila were passed through the unit. The draft tube helped achieve a comparatively uniform grain temperature (±4°C) and minimized heat losses. Three target grain temperatures (55, 57 and 60°C) were achieved during the experiment. After initial heating, the 2 lower temperatures were maintained for periods of time likely to ensure disinfestation of R. dominica. No live insects were found after the heat treatment. The grain residence time was less than 1 second. The throughput of the system was 5 t/h, which was limited by the capacity of the pneumatic conveyor used to feed the infested grain into the heating chamber. However, the maximum capacity of the system could be as much as 10 t/h. Practical considerations for the scale up and commercialization of the spouted-bed disinfestor are the next steps in making this technology available to the end users.
The survival of developmental Sitophilus granarius (L.) subjected to constant and fluctuating temperatures between 0 and 10°C.
Authors: Fleming D. A. , Armitage D. M.
Published: November 2017

Surface infestations of grain weevils, S. granarius, have occurred during mid-winter in commercial aerated stores and in 20-tonne cooled bins when the grain was stored over 2 seasons and temperatures were rarely above 5°C. It was hypothesised that they were the result of eggs laid in the summer, which had continued to develop through the autumn and early winter and emerged in mid-winter when fluctuating temperatures at the surface permitted this. Therefore, this study was set up to discover what proportion of developing stages of different ages could survive exposure to steady temperatures between 0 and 10°C which coincide with the temperatures attained within the bulk of most stored grain in the UK. The effects of a temperature fluctuating between 0 and 10°C were also studied as this approximates the extreme fluctuations that might be expected at the surface of a cooled bulk in winter. Steady temperatures below 5°C were successful in killing all developmental stages within 7 weeks and are achievable in most years in the UK However, when the temperatures were allowed to cycle between 0 and 10°C, it extended the time needed to eliminate all developing stages to more than 16 weeks. It is unlikely that this temperature-time combination could be achieved in the UK. It is therefore quite likely that a mixed-age infestation of developing grain weevils inside the grain could survive the fluctuating temperatures that occur at the grain surface.
Treatment of an empty fumigation chamber using the Degesch phosphine generator.
Authors: Mathews M. , Luzaich G.
Published: November 2017

A trial fumigation was conducted on an empty fumigation chamber using the Degesch phosphine generator. The Degesch phosphine generator is a device for the rapid production and injection of phosphine gas into structures requiring fumigation. The generator is positioned outside the structure where it generates phosphine by reaction of Magtoxin granules, a high-assay magnesium phosphide product, with water. This reaction is carried out inside the generator under an atmosphere of carbon dioxide. The phosphine (PH3) is then pumped from the generator into the structure through a recirculation system. The generator produces a non-hazardous, aqueous slurry (pH 7) of magnesium carbonate which requires disposal. The carbonate contains less than 0.001% unreacted phosphide. A fumigation chamber with a volume of 2633 m3 (93 000 ft3) was dosed at a rate of 1.1 g PH3/m3 (32 g PH3/ft3). This dosage corresponds to a theoretical concentration of 800 ppm PH3. A concentration of 800 ppm was reached in the chamber approximately 52 minutes after injection of phosphine began. Phosphine concentration measurements were made at the bottom, middle and top of the structure over a 96-hour fumigation. Some advantages of the Degesch phosphine generator are: rapid production of high concentrations of phosphine; lower labour requirement for application, retrieval of spent fumigant, and disposal; ease of redosing or adding back phosphine; generation of phosphine gas is not dependent on ambient temperature or humidity; application may be started and stopped at any time; multiple fumigations can be conducted from a central location using a gas distribution system; worker exposure during application is virtually eliminated; may be used with the J-System, a patented method for the recirculation of phosphine gas, to obtain uniform distribution of phosphine throughout the treated commodity; and can serve as an alternative to methyl bromide.
Effect of fumigation temperature on the efficacy of phosphine against strongly resistant psocids Liposcelis bostrychophila (Psocoptera: Liposcelididae).
Authors: Nayak M. K. , Collins P. J. , Pavic H.
Published: November 2017

Four concentrations of phosphine (0.1, 0.17, 0.3 and 1 mg/litre) were evaluated for their effectiveness against the strongly resistant L. bostrychophila at fumigation temperatures of 20, 25, 30 and 35°C. The lowest number of days required to achieve population extinction was evaluated. At any fixed concentration of phosphine, the number of days to population extinction decreased as the fumigation temperature increased from 20 to 30°C. At 0.1 mg/litre and 20°C, more than 14 days were required to completely control the insects; at 30°C, only 7 days were required. The increase in the fumigation temperature from 25 to 30°C substantially reduced the exposure period needed to achieve population extinction of resistant psocids.
Prospects for predicting insect mortality in relation to changing phosphine concentrations.
Authors: Daglish G. J. , Collins P. J. , Pavic H.
Published: November 2017

The effects of varying phosphine concentrations (0.2, 0.4 and 0.43 mg/litre) on phosphine-resistant Rhyzopertha dominica (QRD569) and Sitophilus oryzae (QSO335) strains from Australia were studied under fumigation (25°C and 55-60% relative humidity) and post-fumigation (25-28°C and 55-60% relative humidity) conditions to evaluate the prospect of predicting insect mortality under varying phosphine concentrations. The commonly used concentration × time product was unreliable for the prediction of R. dominica and S. oryzae mortality. On the other hand, the relationship Cnt=k may be useful for R. dominica. However, in the case of S. oryzae, the relationship Cnt=k proved to be less reliable.
The efficacy of flufenoxuron and azadirachtin against mixed mite and insect populations in small bins of wheat.
Authors: Collins D. A.
Published: November 2017

Alternatives to the use of organophosphorus compounds for the protection of stored grain against pest infestations were investigated. Batches of wheat (cv. Mercia) were treated with 2 mg flufenoxuron and 75 mg azadirachtin/kg, transferred into small bins infested with mixed populations of mites and insects (Acarus siro, Lepidoglyphus destructor, Sitophilus granarius and Oryzaephilus surinamensis) and stored at 15°C and 80% relative humidity for 26 weeks. From the second week, efficacy was evaluated every four weeks based on the ability of the compounds to inhibit the development and survival of the pest species. A. siro or L. destructor were not detected in the samples treated with flufenoxuron at or after 6 and 10 weeks, respectively. In the azadirachtin-treated samples, mites were not detected at weeks 2 and 26, when A. siro were found in one of the bins. L. destructor was not detected in any of the untreated samples after week 14, which may have been due to competition from the faster breeding A. siro. Adult beetles were caught in the traps throughout the experiment, with lower numbers of O. surinamensis trapped than S. granarius. The treatments reduced the numbers of S. granarius by approximately 75%.
The importance of moisture changes at the grain surface.
Authors: Armitage D. M. , Cook D. A.
Published: November 2017

Studies are presented on seasonal changes in moisture content at the grain surface, diurnal changes in relative humidity (rh) and surface moisture uptake, effect of aeration on surface moisture uptake, effect of bulk moisture content and sealing on surface moisture uptake, and effect of bulk moisture content on mite populations, particularly those conducted on wheat and barley. To evaluate whether surface uptake could be limited to control mite (Acarus siro and Lepidoglyphus destructor) populations, bins containing 25 kg of wheat were held at constant conditions of 15°C and 80% rh, and sealed with shrouds of nylon woven tarpaulin, plastic sheeting (nylon polythene laminate) or butyl rubber, or left uncovered as a control. The controls steadily absorbed moisture and had a median surface mc of 16.3% after 18 weeks. The shrouded replicates also steadily absorbed moisture but the uptake was reduced by 0.5-1%, depending upon the material. The plastic sheeting resulted in the lowest mc and mite infestation (a reduction of approximately 10-fold for A. siro) after 18 weeks.