Dosage rate, temperature, and food source provisioning affect susceptibility of Tribolium castaneum and Tribolium confusum to chlorfenapyr

A series of experiments were conducted to evaluate residual efficacy of the insecticidal pyrrolle chlorfenapyr (Phantom^®) on treated concrete for control of Tribolium castaneum (Herbst), assess development of progeny from exposed parental adults, and to determine if starvation before exposure with or without a flour food source increased susceptibility of adult T. castaneum and adult Tribolium confusum Jacqueline du Val to chlorfenapyr. No adults survived exposure on concrete treated with chlorfenapyr at the maximum label rate of 1.1 g active ingredient (AI)/m², and no progeny were produced in bioassays conducted at 0–8 weeks posttreatment. In the second test, application rates were reduced, and bioassays were conducted at 27 and 32 °C. Adult survival and progeny production decreased as the application rate increased from 28 to 225 mg AI/m², and survival and progeny production were generally lower at 32 °C than at 27 °C, but at higher rates survival was <1 %, and no progeny were produced. In the final test, adult T. castaneum and adult T. confusum were starved for 1–7 days and then exposed either with or without flour on concrete treated with 3.9 and 27.5 mg AI chlorfenapyr/m². Mortality generally increased with starvation time, the presence of a food source led to decreased mortality at both application rates, and T. confusum was the more susceptible of the two species. Results show that chlorfenapyr could effectively control both species, but precise dosage levels need to be determined. Also, the presence of a food source greatly compromises adult control.     

The effects of different rearing diet media on the irradiated pupae and adults of flour beetle,Tribolium confusum (J. du val)

In this study, gamma radiation was applied between 10–120 Gy at 10 dose levels for 2–4 days-old pupae; 10–150 Gy at 11 dose levels for 12–14 days-old adults ofT. confusum. All experiments were carried out in incubators maintained at 27±0.5°C and 70±5% relative humidity. The development of adults reared on different flours from irradiated pupae was not prevented by exposing these stages investigated doses. Rapidly developing confused flour beetle were more susceptible to killing by gamma radiation. Adults that emerged from treated pupa had elytral and other deformities. In barley flour, rate of deformed individuals were higher than the other rearing media. LD₅₀, LD_99,9 and SD_99,9 values for wheat flour were high compared with both barley and maize flour. For adult treatment, there were differences in survival among rearing diets especially at doses of 40, 50 and 60 Gys. But there were no differences for LD₅₀ and LD_99,9 values at adult stage, indicating little influence of rearing medium on susceptibility of adults. On the other hand, there were little differences between rearing diets for SD₅₀ and SD_99,9.With 6 tables and 4 figures     

Comparative performance of the red flour beetle Tribolium castaneum (Coleoptera: Tenebrionidae) on different plant diets

Tribolium castaneum is a pest of stored foods that causes serious economic losses. Understanding insect nutritional requirements and the effects of different diets on insect development can provide tools for developing strategies to control insect and integrated pest management systems. In this work we studied the performance of the T. castaneum on different plant diets composed of Vigna unguiculata, Phaseolus vulgaris and wheat flours. The diets interfered differentially with development and insect survival. Larvae size was reduced about 60 % in larvae fed with V. unguiculata flour. A delay in pupae formation was also observed. The larval mortality of 100 % was observed in the P. vulgaris diet. Carbohydrate and triglyceride showed variations during development and with different diets. Larvae fed with wheat diets showed a high concentration of carbohydrates 21 days after hatching (DAH) and triglyceride at 15 and 21 DAH. Larvae fed with wheat diets showed α-amylase activity during development. At 15 DAH the activity of larvae fed with V. unguiculata increased about 50 %. Cysteine protease activity in larvae fed with wheat remained high throughout development. Serine protease activity also varied according to diets. These results show that the nutritional state of developing larvae varies greatly with respect to triglycerides, carbohydrate and digestive enzymes depending on the diet and larval stage. Altogether, these results show that changes in dietary nutrients can interfere with insect physiology. Therefore changes in diet composition that may deprive insects of essential nutrients or include toxic compounds might be a good control strategy for stored product pests.     

Effects of gamma radiation on life stages of the Mediterranean flour moth, Ephestia kuehniella Zeller (Lepidoptera: Pyralidae)

We report the results of experiments conducted with Ephestia kuehniella Zeller to determine the effects of gamma radiation on life stages. Eggs, larvae, pupae and adults were irradiated with increasing doses of gamma radiation (seven dose levels between 50 and 400 Gy for eggs and larvae, six dose levels between 50 and 350 Gy for pupae and four dose levels between 250 and 550 Gy for adults). All the experiments were conducted in a growth chamber maintained at 27 ± 1°C, 65 ± 5% r.h., and alternating 14 h light:10 h dark cycles. The number of adults that developed from irradiated eggs and larvae was lower than the untreated control. Doses of 200 Gy and above prevented adult emergence from irradiated eggs. Although a dose of 200 Gy was enough to prevent adult emergence from young larvae, 250 Gy should be used to prevent adult emergence completely from last instar larvae. Delayed developmental periods were observed for the treated eggs and larvae. Fecundity and egg hatchability were decreased depending on the doses applied. Decreased fecundity and egg hatchability were more prevalent when both the male and female pupae were treated compared to the treatment of female pupae only. There was no significant decrease in the fecundity of irradiated adults except 550 Gy, and no eggs hatched at doses of 300 Gy and above.     

Treatment of rice with diatomaceous earth and effects on the mortality of the Red flour beetle Tribolium castaneum (Herbst)

Diatomaceous earth has been demonstrated in Australia, Germany, and the USA to protect stored products from infestation by insect pests. However, application of diatomaceous earth has rarely been used in Asian countries for the protection of stored grain from insect damage. These facts and the paucity of existing data from the tropics prompted the present study of storage with diatomaceous earth. We exposed rice treated with the diatomaceous earth product Fossil Shield® to infestation by Tribolium castaneum Herbst. During the dry season, when tests were conducted, the mean temperature was 29?±?2?°C and relative humidity was 80?±?3?%. The population of T. castaneum in rice was significantly reduced after treatment with Fossil Shield®. Diatomaceous earth at 1?g and 2?g per kilogram rice reduced population growth of T. castaneum to a coefficient of 0.27, and 0.02 respectively after 42 days. Fossil Shield® at 0.5?g per kilogram rice increased the mortality of T. castaneum, but did not stop population growth.     

Age effects and climate response in trees: a multi-proxy tree-ring test in old-growth life stages

Aging in trees implies a progressive reduction in the growth rate, related to a shortening of the growing period and changes in the photosynthetic capability and efficiency. These changes may continue during the old-growth life stages following the juvenile phase and are reflected in tree-ring properties such as growth increment, density or stable isotopes. We studied possible climate age effects in time series of several tree-ring parameters (ring width, wood density and stable carbon and oxygen isotopes) of mature individuals from two age groups of Pinus uncinata and P. nigra at two locations in Spain. The aim was to test whether age differences in trees in the old-growth life stages could lead to diverging climate responses. The results show some differences in response to climate between age groups at a monthly level, but most of these divergences are not significant for seasonal climate variables. Regardless of the age group, the main limiting climate factors constrained tree growth equally. Although our findings do not support the idea of an age-dependent response to climate that may lead to inaccurate climate reconstructions, further studies using tree-ring density and stable isotope series are urgently needed to verify the current results.     

Chemical composition,insecticidal and biochemical effects of essential oils of different plant species from Northern Egypt on the rice weevil,Sitophilus oryzae L.

The extensive use of synthetic insecticides and fumigants for control stored-product insects has led to the development of resistance. Essential oils from aromatic plants may provide proper alternatives to currently used insect control agents. Essential oils from 20 Egyptian plants were obtained by hydrodistillation. The chemical composition of the oils was identified by gas chromatograph/mass spectrometer. Fumigant and contact toxicities of the essential oils were evaluated against Sitophilus oryzae. The inhibitory effects of the essential oils on acetylcholinesterase and adenosine triphosphatases activities were examined. The oils were composed of monoterpene hydrocarbons (i.e., limonene, sabinene, β-pinene and γ-terpinene) and oxygenated monoterpenes (i.e., terpinen-4-ol, β–thujone, 4-terpineol, α-citral and 1,8-cineole) with the exception of the oil of Schinus terebinthifolius which was contained sesquiterpenes, and the oil of Vitex agnus-castus which contained similar amounts of monoterpenes and sesquiterpenes. In the fumigation assay, the oils of Origanum vulgare (LC₅₀ = 1.64 mg/L air), Citrus lemon (LC₅₀ = 9.89 mg/L air), Callistemon viminals (LC₅₀ = 16.17 mg/L air), Cupressus sempervirens (LC₅₀ = 17.16 mg/L air), and Citrus sinensis (LC₅₀ = 19.65 mg/L air) showed high toxicity to S. oryzae. In the contact assay, the oils of Artemisia judaica, C. viminals, and O. vulgare caused the highest toxicity to S. oryzae with LC₅₀ values of 0.08, 0.09, and 0.11 mg/cm², respectively. The oil of A. judaica (I₅₀ = 16.1 mg/L) invoked the highest inhibitory effect on AChE activity, while the oils of C. viminals and O. vulgare were the most potent inhibitors to ATPases activity with I₅₀ values of 4.69 and 6.07 mg/L, respectively. The results indicate that the essential oils of A. Judaica, O. vulgare, C. limon, C. viminals, and C. sempervirens could be applicable to the management of populations of S. oryzae.     

Trees for life: The ecosystem service contribution of trees to food production and livelihoods in the tropics

Despite expanding interest in ecosystem service research over the past three decades, in-depth understanding of the contribution of forests and trees to food production and livelihoods remains limited. This review synthesizes the current evidence base examining the contribution of forest and trees to agricultural production and livelihoods in the tropics, where production often occurs within complex land use mosaics that are increasingly subjected to concomitant climatic and anthropogenic pressures. Using systematic review methodology we found 74 studies investigating the effect of forest or tree-based ecosystem service provision on a range of outcomes such as crop yield, biomass, soil fertility, and income. Our findings suggest that when incorporating forests and trees within an appropriate and contextualized natural resource management strategy, there is potential to maintain, and in some cases, enhance yields comparable to solely monoculture systems. Furthermore, this review has illustrated the potential of achieving net livelihood gains through integrating trees on farms, providing rural farmers with additional income sources, and greater resilience strategies to adapt to market or climatic shocks. However, we also identify significant gaps in the current knowledge that demonstrate a need for larger-scale, longer term research to better understand the contribution of forest and trees within the broader landscape and their associated impacts on livelihoods and food production systems.     

Insecticidal efficacy of <Emphasis Type="Italic">Isaria farinosa</Emphasis> in different life stages of <Emphasis Type="Italic">Pissodes punctatus</Emphasis> (Coleoptera: Curculionidae)

The insecticidal activity of an entomopathogenic fungus, Isaria farinosa on pine bark-weevil (Pissodes punctatus) at different life stages underwent laboratory testing. Larvae, pupae and adults of Pissodes punctatus were exposed to a range of concentrations of fungal conidia in suspension for 5 s; mean mortality and LC₅₀ values were calculated. The results showed I. farinosa can effectively infect larvae, pupae and adult pine bark-weevils, and the highest mean mortalities at each life stage can exceed 88%. The mean mortalities increased with higher concentrations of I. farinosa. Larvae were most susceptible with LC₅₀ 1.2 × 10⁶ conidia ml⁻¹ (15 days), pupae (30 days) exhibited the second largest effects, and adults (15 days) with LC₅₀ 1.72 × 10⁶ and 1.99 × 10⁶ conidia ml⁻¹, respectively, at end of the experiments. This suggests that I. farinosa could be a potential bio-control agent against the pine bark-weevil.     

不同复合经营模式对杨树蛀干害虫天牛控制效果的调查研究

杨树人工林复合经营模式对杨树蛀干害虫天牛控制效果和复合经营的效益结果表明,5种复合经营模式与纯林相比,杨树天牛虫口密度下降了87．94％-97．16％,有虫株率下降了81．11％-96．17％,复合经济收益有显著增加。同时,综合评估了不同复合经营模式的效益。分析显示,以林渔模式的综合效益最佳;林农（油）模式的控制天牛效果最好,林牧模式次之。采用林菌模式可获得更长期的复合经营效益。     

Effects of environmental factors on plant functional traits across different plant life forms in a temperate forest ecosystem

New Forests - Plant functional traits have been shown to vary with environmental conditions. However, we lack empirical data on how plant functional traits of different plant life forms respond to...     

Effect of oilseed type on the efficacy of five diatomaceous earth formulations against <Emphasis Type="Italic">Tribolium castaneum</Emphasis> Herbst (Coleoptera: Tenebrionidae)

The insecticidal efficacy of five diatomaceous earth (DE) formulations, Protect-It^®, SilicoSec^®, Insecto^®, Perma-Guard^? D-10 and Dryacide^® was evaluated against adult Tribolium castaneum Herbst, the red flour beetle, on three oilseeds: safflower, sunflower and sesame. The DE formulations were applied at three rates: 0.5, 1 and 1.5 g/kg. The experiment was carried out at 26°C and 55 (±5)% RH in the dark. The mortality of T. castaneum adults was measured after 3, 7, 14 and 21 days exposure. After the 21-day mortality count, all surviving insects were removed and the samples retained under the same conditions for a further 45 days to assess progeny production (F1). Significant differences were recorded among the three oilseed types as well as between the DE formulations tested. After 21 days exposure, even at the lowest treatment rate, adult mortality was high (>90%) in safflower for all DE formulations. In contrast adult mortality was significantly lower in the case of sesame. Increased application rates improved the efficacy of DEs in sunflower and sesame. Even at the lowest rate the complete suppression in progeny production was achieved on treated safflower. The greatest number of progeny was recorded for treated sunflower seeds. Protect-It^® and Dryacide^® were the most efficient DE formulations against T. castaneum.     

Physiological effects of wood on humans: a review

It is empirically known that wood can cause a comfort enhancement effect in humans. On the other hand, not enough scientific knowledge based on evidence-based research is available on this subject. However, data using physiological indices have increasingly accumulated in recent years. This review provides an overview of the current situation for peer-reviewed reports related to the physiological effects of wood. We reviewed reports that elucidated the effects of wood-derived stimulations on the olfactory, visual, auditory, and tactile sensations using physiological indices such as brain activity (e.g., near-infrared spectroscopy) and autonomic nervous activity (e.g., heart rate variability and blood pressure). It became clear that many studies were limited by (1) a small number of participants, mostly aged in their 20s; (2) use of only a single stimulus (e.g., only olfactory or only visual), or (3) an incomplete experimental design. In addition, this review examined the field of forest therapy, for which there is abundant research. Further study is needed to elucidate the physiological effects of wood on humans.     

Environmental load of solid wood floor production from larch grown at different planting densities based on a life cycle assessment

As one of the main structural units in a building,a solid wood floor has significant strategic research value for low-carbon energy saving.Taking the production line of a solid larch wood floor as a case study,we assessed the environmental load during production based upon a life cycle assessment.Using GaBi 6.0 software,we analyzed the associated carbon sequestration during floor production,with the initial planting density serving as the disturbance factor in a modular analysis.The results indicated that the cutting and finishing steps have relatively intense,negative influences on the environment,whereas transportation,ripping,and trimming do not.Additionally,recycling biomass waste has the potential to reduce greenhouse gas emissions.When the initial planting density was 3.0×3.0 m,carbon sequestration was relatively high.Although the emissions of freshwater pollutants,volatile organic compounds,and fine particulate matter(matter with a 2.5-μm diameter) were comparatively high,the reduction of greenhouse gas emissions was still excellent at this planting density.     

Impact of agricultural adjuvants on the toxicity of the diamide insecticides chlorantraniliprole and flubendiamide on different life stages of the navel orangeworm (<Emphasis Type="Italic">Amyelois transitella</Emphasis>)

The navel orangeworm (Amyelois transitella) (Walker) is a destructive pest of tree nuts in California orchards. Overall demand for these crops and acreage expansions have resulted in significant insecticide applications to reduce A. transitella damage. Despite widespread use in A. transitella insecticide applications, the potential toxicity of adjuvants applied in combination with insecticides remains uncharacterized. In these experiments, five adjuvants (Cohere^®, Dyne-Amic^®, FastStrike^®, Induce^®, Latron B-1956^®), alone and in combination with the diamide insecticides chlorantraniliprole (Altacor^®) and flubendiamide (Belt^®), were assessed for activity against the adults and eggs of A. transitella. Laboratory studies utilized a spray tower for application while field studies used orchard air-blast sprayers. Laboratory exposure of both adults and eggs demonstrated that adjuvant toxicity varied across life stages. In the laboratory, the addition of chlorantraniliprole to adjuvants increased incapacity (dead + moribund). The results for flubendiamide were variable, and only FastStrike had the same high adult toxicity for both diamides. For eggs exposed to these diamides, overall mortality was similar. In field studies, Dyne-Amic and Latron B-1956 were tested and their adult toxicity varied. In contact assays, effects of adjuvants were similar when used with Belt^® and differed when used with Altacor^®. We conclude that the adjuvants for navel orangeworm management are intrinsically toxic to A. transitella in both the laboratory and field. Further studies are needed to attain the toxicity realized in the laboratory in field applications and also to determine whether our findings of adjuvant enhancement of insecticide toxicity are applicable to other insecticide classes.     

Synergistic effects of tropical cyclones on forest ecosystems:a global synthesis

Tropical cyclones are large-scale strong wind disturbance events that occur frequently in tropical and subtropical coastal regions and often bring catastrophic physical destruction to ecosystems and economic disruption to societies along their paths. Major tropical cyclones can infrequently move into the midaltitudes and inland areas. Ecologically, tropical cyclones have profound impacts on diversity, structure, succession and function of forest ecosystems. The ecological effects are both dramatic and subtle. The dramatic effects can be visible, noticeable and to some extent predictable over the short-term and relatively well documented in the literature. However, the subtle effects are often invisible, complex and at smaller scale relatively unpredictable in the long-term. Many factors, meteorologic, topographic and biologic, simultaneously interact to influence the complexity of patterns of damage and dynamics of recovery. I present a global synthesis on the effects of tropical cyclones on forest ecosystems and the complexity of forest responses, with particular attention on the response to large hurricanes in the neotropics and the temperate North America, and strong typhoons on the subtropical and temperate forests in the East and Southeast Asia. Four major aspects provide on organizational framework for this synthesis:(1) consistent damage patterns,(2) factors that influence response patterns and predict damage risks,(3) complexity of forest responses and recovery, and(4) the long-term effects. This review reveals highly variable and complex effects of tropical cyclones on forest ecosystems. A deep understanding of the synergistic effects of tropical cyclones is essential for effective forest management and biodiversity conservation.     

Age effects on Norway spruce (Picea abies) susceptibility to ozone uptake: a novel approach relating stress avoidance to defense

Cumulative ozone (O3) uptake and O3 flux were related to physiological, morphological and biochemical characteristics of Norway spruce (Picea abies (L.) Karst.) trees of different ages. Under ambient CO2 conditions, photosynthetic capacity (Amax) declined in mature trees when cumulative O3 uptake into needles, which provides a measure of effective O3 dose, exceeded 21 mmol m-2 of total needle surface area. A comparable decline in Amax of seedlings occurred when cumulative O(3) uptake was only 4.5 mmol m-2. The threshold O3 flux causing a significant decline in Amax ranged between 2.14 and 2.45 nmol m-2 s-1 in mature trees and seedlings subjected to exposure periods of > or = 70 and > or = 23 days, respectively. The greater O3 sensitivity of young trees compared with mature trees was associated with needle morphology. Biomass of a 100-needle sample increased significantly with tree age, whereas a negative correlation was found for specific leaf area, these changes parallel those observed during differentiation from shade-type to sun-type needles with tree ontogeny. Age-dependent changes in leaf morphology were related to changes in detoxification capacity, with area-based concentrations of ascorbate increasing during tree ontogeny. These findings indicate that the extent of O3-induced injury is related to the ratio of potentially available antioxidants to O3 influx. Because this ratio, when calculated for ascorbate, increased with tree age, we conclude that the ratio may serve as an empirical basis for characterizing age-related differences in tree responses to O3.     

Influence of food supplementation on the fitness of two biological control agents: a predatory nabid bug and a bollworm pupal parasitoid

Many arthropod predators and parasitoids exhibit either stage-specific or lifetime omnivory, in that they include extra-floral nectar, floral nectar, honeydew or pollen in their immature and/or adult diet. Access to these plant-derived foods can enhance pest suppression by increasing both the individual fitness and local density of natural enemies. Commercial products such as Amino-Feed^®, Envirofeast^®, and Pred-Feed^® can be applied to crops to act as artificial-plant-derived foods. In laboratory and glasshouse experiments we examined the influence of carbohydrate and protein rich Amino-Feed UV^® or Amino-Feed, respectively, on the fitness of a predatory nabid bug Nabis kinbergii Reuter (Hemiptera: Nabidae) and bollworm pupal parasitoid Ichneumon promissorius (Erichson) (Hymenoptera: Ichneumonidae). Under the chosen conditions, the provision of either wet or dry residues of Amino-Feed UV had no discernable effect on immediate or longer-term survival and immature development times of N. kinbergii. In contrast, the provision of honey, Amino-Feed plus extrafloral nectar, and extrafloral nectar alone had a marked effect on the longevity of I. promissorius, indicating that they were limited by at least carbohydrates as an energy source, but probably not protein. Compared with a water only diet, the provision of Amino-Feed plus extrafloral nectar increased the longevity of males and females of I. promissorius by 3.0- and 2.4-fold, respectively. Not only did female parasitoids live longer when provided food, but the total number of eggs laid and timing of deposition was affected by diet under the chosen conditions. Notably, females in the water and honey treatments deposited greater numbers of eggs earlier in the trial, but this trend was unable to be sustained over their lifetime. Egg numbers in these treatments subsequently fell below the levels achieved by females in the Amino-Feed plus extrafloral nectar and cotton extrafloral nectar only treatments. Furthermore, there were times when the inclusion of the Amino-Feed was beneficial compared with cotton extrafloral nectar only. Artificial food supplements and plant-derived foods are worthy of further investigation because they have potential to improve the ecosystem service of biological pest control in targeted agroecosystems by providing natural enemies with an alternative source of nutrition, particularly during periods of prey/host scarcity.