Probe Trap Research Articles

Correlation Analysis of Sitophilus oryzae (Linnaeus) Real-Time Monitoring and Insect Population Density and Its Distribution Pattern in Wheat Grain Piles

The traditional manual sampling method for detecting stored grain insect pests is labor-intensive and time-consuming, often yielding non-representative samples. However, to achieve more accurate monitoring, it is necessary to understand the distribution patterns of different insect pests within grain silo and their correlation with monitoring and sampling data. This study aimed to assess the population density and distribution of Sitophilus oryzae (rice weevil) in bulk wheat grain to predict insect dynamics effectively. Utilizing a probe trap in a wheat silo, adult insects were tracked across different population densities. The traps recorded captured pests, alongside temperature and humidity data. The correlation analysis revealed that rice weevils were active throughout the silo but less prevalent at the bottom, with the highest distribution near the upper surface. Temperature and humidity significantly influenced their activity, particularly within the 22 °C to 32 °C range. Higher population densities correlated with increased relative humidity, impacting weevil activity. Trapping data aligned with overall population density changes in the silo. This study will provide an accurate assessment of the population density of adult rice weevils in grain silos based on temperature changes in the upper part of the grain silo.

Evaluation of the Efficiency of Probe and Indicator Device traps for Catch Adults of the Cowpea weevil Callosobruchus maculatus Fab. (Coleoptera: Chrysomeloidea)

The Probe trap was tested with three types (empty, water, alcoholic extract of (Vicia faba) respectively and for three periods of time (1, 2, 3) days respectively to catch the cowpea weevil C. maculatus that infests the broad bean seeds prepared for cultivation. It gave a trap Probe catching percentage on the third day of placing the traps respectively (19.16, 62.5, 88.33)% respectively, and the lowest catching percentage on the first day was (5.83, 20, 41.67%) respectively, while the highest percentage of catch was for the Indicator device trap with three species (Grease as sticky material , water, Vicia faba flower extract) for the third day with placing traps (52.5, 70, 72.5%) respectively, and the lowest percentage of catching was on the first day, which was (27.5, 40, 47.5%) respectively. From the experiment, the efficiency of the Probe trap and the Indicator device trap, to which bean flower extract was added, in hunting C. maculatus adults for the same time period, where the extract increased the efficiency of the two traps, followed by water for the same period of time.

Predicting crop damage caused by wireworms and the effect of tillage on trap efficiency

A novel wireworm ‘probe’ trap is described, characterized, and used in field trials to (i) determine effects of different spring tillage treatments on its efficiency capturing Agriotes obscurus L. Coleoptera: Elateridae wireworms; and (ii) assess its ability to predict crop damage. In pot trials, its attractiveness to other wireworm species was determined. In a forage/grass field, spring tillage treatments included: ploughing, rototilling, glyphosate-sprayed then ploughing, glyphosate-sprayed then rototilling, glyphosate-sprayed untilled, and untilled. The number of wireworms captured in tilled treatments increased until 20 October. The number of wireworms captured in untilled treatments remained low. Subterranean CO2 levels in tilled treatments decreased after tillage and over the trapping period, suggesting the increase in captured wireworms occurred because trap CO2 levels were not overwhelmed by soil levels. The decrease in subterranean CO2 was less pronounced in untilled-glyphosate and relatively unchanged in untilled-no glyphosate, corresponding to the lower number of wireworms captured. In a separate trial determining the trap’s ability to predict crop damage, a 2 m-wide section was rototilled in grass/forage fields in the spring of Year 1. Probe traps assessed wireworm levels in August and October of Year 1 to predict crop damage for potato and corn planted in Year 2. The y-intercept of linear equations suggested that wireworms captured in October better-predicted potato damage and corn emergence although equations were significant only for August. October-captured wireworms ≤ 21 mm in length correlated better with crop damage than larger wireworms. Pot studies revealed the probe trap to also attract A. litigiousus, A. sordidus, A. brevis, and A. ustulatus.

Optimal Mechanical Exclusion Devices for Management of Khapra Beetle in Stored Wheat

The effect of mechanical exclusion devices and its number in combination viz. probe trap (A; 1-3), two-in-one trap with 3 mm perforations (B; 1-5) and two-in-one trap with 2 mm perforations (C; 1-3) were investigated to test the efficiency of these traps for trapping larvae and adults of khapra beetle Trogoderma granarium Everts. Colour change and weight loss (%) happening in wheat stored in bins of 50 kg capacity for six months were used as the criteria. The experiments were planned using a three-factor-three-level Box and Behnken design of response surface methodology and were optimized for maximum trapping, with minimum change in colour and weight loss. Analysis of variance (ANOVA) revealed significantly (p<0.05) higher effects of quantity (number) of two in one trap with 3 mm perforations followed by two in one trap with 2 mm perforation on total trapping efficiency. Colour change and weight loss in stored wheat exhibited a negative relationship with trap capture. Among the process parameters studied, the probe trap and its number in experimental combination demonstrated a significantly lower effect on the response variables. The optimal combinations of mechanical exclusion process parameters obtained by numerical optimization technique for trapping larvae and adults were 3:4:3 and 2:5:3 (probe trap: two in one model trap 3 mm: two in one model trap 2 mm) with desirability of 0.61 and 0.63, respectively.

Keefektifan tiga jenis perangkap serangga untuk deteksi serangga hama gudang yang menyerang bungkil kopra

Serangga hama gudang dapat menyebabkan penolakan konsumen dan kerugian ekonomi berkaitan dengan masalah mutu atau persyaratan fitosanitari. Keefektifan perangkap serangga pada komoditas bungkil kopra yang disimpan masih belum banyak diketahui. Penelitian dilakukan untuk menentukan keefektifan tiga jenis perangkap serangga dalam mendeteksi serangga hama gudang pada bungkil kopra. Perangkap serangga yang diuji terdiri atas perangkap jebakan, perangkap colokan, dan perangkap cahaya dari lampu ultraviolet (UV) blacklight dan LED (light emiting diode). Penelitian dilakukan di Laboratorium Entomologi SEAMEO BIOTROP dan dua gudang penyimpanan bungkil kopra (GPBK) di Bitung, Sulawesi Utara. Percobaan di laboratorium menggunakan rancangan acak lengkap faktorial yang terdiri atas dua faktor dan empat ulangan. Faktor pertama adalah jenis perangkap serangga, yaitu perangkap jebakan, perangkap colokan, dan perangkap colokan dengan LED UV dan faktor kedua adalah spesies serangga, yaitu Tribolium castaneum (Herbst) dan Lasioderma serricorne (Fabricius). Percobaan di gudang penyimpanan menggunakan rancangan acak kelompok tersarang, yaitu spesies serangga terperangkap tersarang pada masing-masing perangkap serangga yang digunakan di GPBK. Hasil pengujian di laboratorium menunjukkan perangkap colokan lebih banyak menangkap serangga (30,4%) yang berbeda nyata dibandingkan dengan perangkap jebakan (17,3%), tetapi serangga yang tertangkap tidak berbeda nyata antara perangkap colokan dengan perangkap colokan dengan LED UV (21%). Pengujian di gudang menunjukkan bahwa perangkap colokan lebih efektif dalam memerangkap T. castaneum dan Tenebroides mauritanicus dibandingkan perangkap serangga lainnya, sedangkan perangkap colokan dengan LED UV lebih efektif dalam mendeteksi L. serricorne and Necrobia rufipes (Fabricius) di GPBK.

Studies on the comparative efficiency of different traps in attracting various storage pests in paddy seed processing units

Experiments were conducted to compare the efficiency of four different kinds of traps namely TNAU insect probe trap, TNAU pit fall trap, Indicator device and Stack probe trap and then indicator device against normal sampling method to collect insects present in processed and stored paddy seeds at a particular time interval. The direct comparison of efficiency of traps in collecting rice weevil, Sitophilus oryzae, red flour beetle Tribolium castaneum Herbst, angoumois grain moth, Sitotroga cerealella Oliver and lesser grain borer, Rhizopertha dominica Fabricious which are of economic importance on 30, 60, 90, 120 and 150 days after well processed and sampled seed lots. It was found that maximum number of pests was collected in stack probe trap followed by TNAU insect probe trap before and after fumigation. Among the pests lesser grain borer was collected more followed by angoumois grain moth.

Mapping the restoring force of an optical trap in three dimensions using a two laser dual-trap approach

A two laser optical tweezers set-up is developed and used to measure deflections of a microsphere trapped in a calibrated spatial light modulator steered probe trap as it is stepped through a three dimensional grid about a fixed test trap. These measurements are used to map the restoring force of the test trap on the microsphere in three dimensions. Results are validated over a common range by comparison to drag force measurements for both silica and polystyrene microspheres.

Tools for stored product insects management and technology transfer

Food grains are stored in farm, home or warehouses and insects continue to create problems by causing qualitative and quantitative damage in storage. This necessitates the use of tools for early detection (probe trap, pit fall trap and stack probe trap- Indian Patent Application No.1733/CHE/2008, dt.24.7.2008, early adult removal (Insect removal bins), or for control (Insect egg removal device- Indian Patent No. 198434, and UV Light trap). These tools have become essential in the current scenario of “Global Food security”. Attempts were made to transfer these tools namely viz., TNAU insect probe trap, Pitfall trap, Two-in-one trap, Indicator device, Automatic insect removal bin, Egg remover device, Stack probe trap and UV Light trap for warehouse, to end users in a systematic and scientific way following the basic principles of agricultural extension. The methods used were by developing entrepreneurs for continuous supply of the tools, feedback studies in various states of India, by conducting training to end users and reaching students of agricultural colleges through developing a “Educational Kit” with multimedia, hosting the trapping devices on many websites and publishing details of the tools in popular magazines. A significant impact has resulted because of these exercises in terms of end users of the technologies.

Probing surface states in PbS nanocrystal films using pentacene field effect transistors: controlling carrier concentration and charge transport in pentacene.

We used a bilayer field effect transistor (FET) consisting of a thin PbS nanocrystals (NCs) film interfaced with vacuum-deposited pentacene to probe trap states in NCs. We interpret the observed threshold voltage shift in context of charge carrier trapping by PbS NCs and relate the magnitude of the threshold voltage shift to the number of trapped carriers. We explored a series of NC surface ligands to modify the interface between PbS NCs and pentacene and demonstrate the impact of interface chemistry on charge carrier density and the FET mobility in a pentacene FET.

Efficiency of Stack Probe Trap for Detection, Validation of Fumigation and Distribution of Stored Grain Insects in Bag Stacks

Efficiency of Stack Probe Trap for Detection, Validation of Fumigation and Distribution of Stored Grain Insects in Bag Stacks

Occurrence of Insects in Stored Cocoa Beans in Tamil Nadu

Investigations were carried out on insects associated with stored cocoa beans in private godowns at Sennakallpalyam, Dharapuram in Tamil Nadu, India during 2010-2011. The tools used were normal sieve sample, UV light trap, pheromone trap and stack probe trap. The survey indicates the presence of 10 insect species namely ; Lasioderma serricorne (F.), Tribolium castaneum (Herbst.), Araecerus fasciculatus (De Geer), Prostephanus truncates (Horn), Carpophilus sp. (Erichson) Ephestia sp. (Walker), Hypothenemus sp. (Ferrari), Cryptolestes ferrugineus (Stephens) Liposcelis sp. and Plodia interpunctella (Hubner). These physical method helps for early detection and management of stored grain pest effectively.

Spatial and non-spatial analyses of insect counts in bulk-stored barley

Stored grain insect species in bulk-stored barley were sampled during 15 consecutive weeks in two ways: direct sampling based on grain trier samples and indirect sampling based on probe trap captures. A total number of 22 insect taxa were found; this study focused on the six most abundant species and their natural enemies. Four aspects were addressed: (i) differences in insect counts when based on either probe trap captures or grain trier samples, (ii) usefulness of grain temperature and moisture content as explanatory variables for insect densities, (iii) density-dependent relationships between natural enemies and their hosts, and (iv) spatial and non-spatial analyses of insect counts. Both total captures and frequencies of insect taxa were consistently higher in captures with probe traps than insect numbers obtained from grain samples. Regression analysis with abiotic conditions and probe trap captures as explanatory variables provided good fits to insect counts in grain samples for four of the six insect species (R2-values>0.40). Using multi-regression analyses, we showed that: (i) the occurrence of natural enemies was only weakly associated with the abundance of hosts; (ii) grain moisture content and temperature appeared to be at least as important variables as host availability; and (iii) the predictive strengths of regression models were similar when based on either data from grain samples or probe traps. Spatial analyses (SADIE) of both sampling data suggested that all data sets followed a spatially random distribution; re-arrangement of the data provided insight into important aspects of SADIE analyses of small data sets. Non-spatial analysis (Lloyd's aggregation index) showed significant differences among species and that the level of non-spatial aggregation was quite sensitive to sampling method used.

Predicting Stored Grain Insect Population Densities Using an Electronic Probe Trap

Manual sampling of insects in stored grain is a laborious and time-consuming process. Automation of grain sampling should help to increase the adoption of stored grain integrated pest management. A new commercial electronic grain probe trap (OPI Insector) has recently been marketed. We field tested OPI Insector electronic grain probes in two bins, each containing 32.6 tonnes of wheat, Triticum aestivum L., over a 2-yr period. We developed new statistical models to convert Insector catch into insects per kilogram. We compared grain sample estimates of insect density (insects per kilogram of wheat) taken near each Insector to the model-predicted insect density by using Insector counts. An existing expert system, Stored Grain Advisor Pro, was modified to automatically read the Insector database and use the appropriate model to estimate Cryptolestes ferrugineus (Stephens), Rhyzopertha dominica (F.), and Tribolium castaneum (Herbst) density from trap catch counts. Management decisions using Insector trap-catch estimates for insect density were similar to those made using grain sample estimates of insect density for most sampling dates. However, because of the similarity in size of R. dominica and T. castaneum, the software was unable to differentiate counts between these two species. In the central and southern portions of the United States, where both species frequently occur, it may be necessary to determine the proportion of each species present in the grain by manual inspection of trap catch. The combination of SGA Pro with the OPI Insector system should prove to be a useful tool for automatic monitoring of insect pests in stored grain.

Laboratory evaluation of traps for the detection of beetle pests in bulk grain

Traps have been evaluated against three species of storage beetle in plastic bins containing 150 kg wheat. The bins were used to generate data for a comparison of the trapping effectiveness of the pitfall cone (PC), pitfall beaker and insect probe traps. The data produced reflect those obtained from field studies and illustrate the advantages of this method over less rigorously controlled field trials. The PC trap, a single type developed to replace both of the previously recommended traps, buried to a 5 cm depth in grain, was as effective as the insect probe for detecting Cryptolestes ferrugineus. The buried PC trap was also as effective as the insect probe trap for trapping Oryzaephilus surinamensis below the grain surface, and the PC trap on the surface was as effective as the pitfall beaker trap. The PC trap below the surface was more effective for trapping Sitophilus granarius than the insect probe trap. This pilot-scale method is a cost-effective alternative to field-scale trials and could be used to investigate various factors influencing trap catch.

Simple technique to increase the sensitivity of probe traps in detecting Cryptolestes ferrugineus (Coleoptera: Laemophloeidae) in stored wheat

AbstractAn approach to enhance the performance of probe traps in detecting Cryptolestes ferrugineus (Stephens) adults in stored wheat is described. The repellent property of protein-enriched pea flour is exploited to increase the efficiency of the probe trap by treating the stored grain with the flour. The enhancement in performance of the traps was evaluated by placing the traps in wheat grains treated with protein-enriched pea flour at concentrations of 1%, 5%, and 10% (w/w) and observing the number of adult beetles trapped in comparison with the trap catch in untreated wheat. The traps kept in wheat treated with protein-enriched pea flour caught more beetles than traps placed in untreated wheat. The practical implications of this work are discussed with reference to sampling for C. ferrugineus.

Relationship Between Flight Activity Outside Grain Bins and Probe Trap Catches Inside Grain Bins ofCryptolestes Ferrugineus

Insect sampling/monitoring inside grain bins is time consuming, cumbersome during the summer heat in the headspace of grain bins, may require investment in costly sampling devices for sampling of grain, and involves a certain risk to employees. Thus, it is important to explore unbaited sticky traps on the outside of grain elevators as decision support tools for improved management of stored grain. In this study, we analyzed seven trap catch data sets of unbaited sticky trap catches on the outside of grain bins and corresponding probe trap catches in the upper level of the grain mass at three farm bins in 1991, with capacities ranging from 68 to 141 metric tons, and at two commercial steel bins in 1993 and 1994, with capacities of 5,400 and 6,800 metric tons. We used response surface regression analysis to analyze standardized trap catches of the rusty grain beetle, Cryptolestes ferrugineus, and showed that (1) from late June to late July, catches on unbaited sticky traps placed on the outside of grain bins preceded probe traps inside the bins by ≈3 d, which suggested immigration into bins; and (2) in late August, unbaited sticky trap catches on the outside of bins started to decrease, while probe trap catches inside the bins continued to increase until mid-September. We concluded that, from late June to mid-August, immigration of C. ferrugineus individuals into grain bins influences abundance in the upper grain layer, whereas later in the season, the two types of trap catches were only loosely associated. This study is consistent with results published elsewhere that immigration of C. ferrugineus into grain bins initiated shortly after wheat was loaded into the bins.

Arena size, hole density, and capture of Oryzaephilus surinamensis (Coleoptera: Silvanidae) in grain probe traps.

The relationship of size of test arena, number of holes in a grain probe trap body and capture of the sawtoothed grain beetle, Oryzaephilus surinamensis (L.), was determined in simulated field tests conducted in an outdoor screen enclosure exposed to natural temperature fluctuations. Polyvinylchloride (PVC) probe bodies were attached to electronic sensor heads, and insect captures were recorded electronically using an electronic grain probe insect counter (EGPIC) system. In comparisons among PVC probe trap bodies with 60, 132, 252, and 492 holes, tested at 18 insects per kilogram in 4.5, 17, and 40 kg of soft wheat in cylindrical arenas (10.2, 20.3, and 30.5 cm in diameter, respectively), number of holes in the probe trap body had no effect on insect capture, but percentage of insects recovered was indirectly related to size of the test arena. Periodicity of insect capture was determined using the time-stamp data that were recorded by the EGPIC system. Circadian rhythm was observed in the periodicity of the capture that corresponded to foraging activity peaks documented for sawtoothed grain beetles, with activity peaks occurring early in the scotophase. There were shifts in times of peak activity among the different test arena sizes that corresponded to differences in temperature in the grain mass. Increases in both temperature and contact between insects and grain probe in the smallest arenas resulted in higher capture of sawtoothed grain beetles. This research documents additional important factors when evaluating capture of sawtoothed grain beetles in grain probe traps.

Hole density and capture of stored-product insect pests in grain probe traps.

The relationship between number of holes in a grain probe trap body and capture of stored-grain pests was determined in laboratory tests using adults of the rice weevil, Sitophilus oryzae (L.), the sawtoothed grain beetle, Oryzaephilus surinamensis (L.), and the red flour beetle, Tribolium castaneum (Herbst). Polyvinylchloride (PVC) probe bodies were attached to electronic sensor heads, and insect captures were recorded electronically using an Electronic Grain Probe Insect Counter (EGPIC) system. In comparisons among PVC probe trap bodies with 60-492 holes, tested at 71 insects per kg in 2.8 kg of soft wheat in cylindrical mini-silos, sawtoothed grain beetle and rice weevil captures were directly related to number of holes in the probe trap body, but there was no relationship for red flour beetle capture. Subsequent tests were conducted comparing sawtoothed grain beetle and rice weevil captures in a PVC probe body with 210 holes over a 40-cm long trapping surface with two commercially available probe traps, a polycarbonate (Lexan) probe trap with 180 holes over a 14-cm long trapping surface and a polyethylene (WBII) probe trap with 750 holes over a 34-cm long trapping surface. The highest percentage capture of both species was in the WBII probe trap, but the 210-hole PVC probe body was as effective as the Lexan probe body for rice weevils and sawtoothed grain beetles at 71 and 17 insects per kg of wheat, respectively.

Factors Affecting Capture of <I>Cryptolestes ferrugineus</I> (Coleoptera: Laemophloeidae) in Traps Placed in Stored Wheat

Cryptolestes ferrugineus (Stephens), the rusty grain beetle, infests grain externally and is a common pest of stored wheat throughout the world. Detection and population estimation of this insect are important in avoiding discounts at the point of sale. Laboratory experiments compared number of insect captures in the WNB II probe and PC trap in stored grain with a known insect density. Capture rates were strongly related to insect densities in wheat. In a simultaneous test of insect density, ranging from one to three insects per kilogram, and temperatures between 20 and 40 degrees C, insect captures in WB II probe traps increased linearly with insect density in the grain but had a quadratic response to temperature. Hole density, ranging from 40 to 120 holes along a 15-cm stretch of the trap body, was unrelated to number of insect captures. Probe trap diameters ranging from 26 to 60 mm were also unrelated to insect captures. Finally, dead rusty grain beetles were recovered in probe traps. The recovery of dead insects increased with insect density when insects were found in an aggregated dispersal pattern, such as would be found following phosphine fumigation of grain. Experiments discussed here will help grain managers understand how probe traps may be used in C. ferrugineus population estimation.

A COMPUTER-BASED INSECT MONITORING SYSTEM FOR STORED-PRODUCTS USING INFRARED SENSORS

Insect infestations in stored agricultural commodities result in annual losses of millions of dollars. Traditional practices for detecting and quantifying infestations in stored-grain involve the labor intensive steps of obtaining and visually inspecting grain samples. The Electronic Grain Probe Insect Counter (EGPIC) system was developed to provide automated real-time monitoring of insects in stored-products. Insect counts from an array of electronic grain probes distributed throughout a storage volume are transmitted to a central computer for display and temporal analysis. A count occurs when an insect, upon entering a cylindrical perforated tube (a commercial grain probe trap), drops through an infrared beam projected within a custom designed sensor head attached to the bottom of the tube. The sensor head was designed to resist dust accumulating and insects crawling in the beam pathway, which would result in counting errors. For large-scale implementations, a tree-structured (distributed multiplexing) network was developed for computer acquisition of insect count data from up to a million addressable probes with a minimal amount of cable. In laboratory trials with major stored-product beetle pests, the EGPIC system counting accuracy was greater than 95%. A field trial with an eight-probe system was conducted during the summer of 1996 with newly stored oats in a commercial grain bin. Overall accuracy of the system was 79% in counting insects on a per-probe basis. Thus, by providing early detection of emerging infestations, the EGPIC system can allow managers to initiate targeted control measures on an as-needed basis but before substantial losses occur.