Combined Effects of UVR and Temperature on the Survival of Crab Larvae (Zoea I) from Patagonia: The Role of UV-Absorbing Compounds

The aim of our study was to assess the combined impact of UVR (280–400 nm) and temperature on the first larval stage (Zoea I) of three crab species from the Patagonian coast: Cyrtograpsus altimanus, C. angulatus, and Leucippa pentagona. We determined the survival response of newly hatched Zoea I after being exposed for 8–10 h under a solar simulator (Hönle SOL 1200) at 15 and 20 °C. There was no mortality due to Photosynthetic Active Radiation (PAR, 400–700 nm) or ultraviolet-A radiation (UV-A, 315–400 nm), and all the observed mortality was due to ultraviolet-B radiation (UV-B, 280–315 nm). The data of larval mortality relative to exposure time was best fit using a sigmoid curve. Based on this curve, a threshold (Th) and the lethal dose for 50% mortality (LD₅₀) were determined for each species. Based on the Th and LD₅₀, C. altimanus was found to be the most resistant species, while L. pentagona was found to be the most sensitive to UV-B. For both species of Cyrtograpsus, mortality was significantly lower at 20 °C than at 15 °C; however, no significant differences between the two temperature treatments were found in L. pentagona. Bioaccumulation of UV-absorbing compounds in the gonads and larvae of C. altimanus, and to a lesser extent in C. angulatus, might have contributed for counteracting the impact of UV-B. However, most of the resilience to UV-B observed with the increase in temperature might be due to an increase in metabolic activity caused by a repair mechanism mediated by enzymes.     

Efficacy of Plectranthus glandulosus (Lamiaceae) and Callistemon rigidus (Myrtaceae) Leaf Extract Fractions to Callosobruchus maculatus (Coleoptera: Bruchidae)

As part of on-going efforts to use eco-friendly alternatives to chemical pesticides, methanol crude extracts of Plectranthus glandulosus and Callistemon rigidus leaves were sequentially fractionated in hexane, chloroform, ethyl acetate, and methanol to establish the most active fraction(s) against Callosobruchus maculatus in cowpea. Cowpea seeds (25 g) were treated with 0.5, 1, 2, and 4 g/kg of extract to evaluate the contact toxicity and F₁ progeny production of the beetles in the laboratory. Mortality was recorded 1, 3, and 7 d postexposure. P. glandulosus hexane fraction was more toxic than the other fractions recording 100% mortality at 4 g/kg, within 7 d with LC₅₀ of 0.39 g/kg. Hexane fraction of C. rigidus showed superior toxicity, causing 100% mortality at 4 g/kg within only 1 d of exposure with LC₅₀ of 1.02 g/kg. All the fractions greatly reduced progeny emergence, with C. rigidus hexane fraction being the best progeny inhibitor. Fractions of P. glandulosus and C. rigidus leaves had sufficient efficacy to be a component of storage pest management package for C. maculatus.     

Influence of Constant Temperature on Reproductive Parameters of Holotrichia oblita (Coleoptera: Scarabaeidae)

Holotrichia oblita Faldermann (Coleoptera: Scarabaeidae) is a major pest both in field crops and forests because the larvae could eat the roots of most crops in the field, and the adults damage the leaves of trees and field crops. In this study, we focused on the effects of temperature on H. oblita reproductive parameters. The results indicated H. oblita female adults at 25°C could lay more eggs (84.0 eggs per female) and have the shortest preoviposition period (19.1 d), the greatest oviposition rate (2.8 eggs per female per 3 d), and largest percentage of life span spent in oviposition (59.5%). The longevity and the time to 50% egg laying decreased with increasing temperature, and female longevity was always longer than male longevity. The preoviposition and postoviposition period decreased with increasing temperature from 15 to 25°C and then increased when the temperature increased from 25 to 30°C. These results show that 25°C is the optimal temperature for reproduction of H. oblita.     

Histopathological Changes in Third-Instar and Adult Anastrepha ludens (Diptera: Tephritidae) After in vitro Heat Treatment

The Mexican fruit fly, Anastrepha ludens Loew (Diptera: Tephritidae), is one of the most harmful pests of mango causing direct damage by oviposition on the fruit pulp. Mango for export is subjected to hydrothermal treatment as a quarantine method for the control of this pest, but exposure to heat for long periods of time reduces considerably the quality and shelf-life of treated fruit. The aim of this work was to study morphological changes of third-instar larvae and adults of A. ludens after in vitro exposure to high temperature at sublethal times. A heating block system was used to expose larvae at 46.1°C for 19.6 and 12.9 min, producing 94.6 and 70% mortality, respectively. Treated larvae were processed for optical microscopy. A fraction of surviving treated larvae was separated into containers with artificial diet to allow development into adults. Adult sexual organs were dissected and processed for transmission electron microscopy analysis. Results showed that 94.6% of the treated larvae died at 46.1°C for 19.6 min and none of the surviving larvae eclosed to adulthood, as they developed as malformed puparia. For the in vitro treatment at 46.1°C during 12.9 min, 70% of the treated larvae died and only 3.75% reached the adult stage, but ultrastructural damage in the male testes and in the female ovaries was observed. Additionally, 11.1% of the adult flies from the in vitro treatment also showed wing malformation and were incapable of flying. The analysis showed that surviving flies were unable to reproduce.     

Survival of Coelaenomenodera lameensis (Coleoptera: Chrysomelidae) in Relation to the Physical Characteristics of Different Oil Palm (Elaeis sp.) Breeding Populations

The edibility of different Elaeis sp. breeding populations present in Benin was tested for the leaf miner Coelaenomenodera lameensis Berti (Coleoptera: Chrysomelidae), a major oil palm pest in Africa. Experiments carried out in sleeves revealed the oviposition capacities of females and the mortality rates for the different developmental stages by comparing the populations found on two breeding populations of Elaeis oleifera (HBK) Cortes, four of Elaeis guineensis Jacquin and four (E. guineensis × E. oleifera) × E. guineensis backcrosses. Females laid their eggs similarly on all breeding populations, with a preference for the E. guineensis La Mé origin. The average hatching rate reached 80% for the La Mé origin as opposed to 28% for the Deli origin. The mortality rates for the larval instars were greater on E. oleifera, on certain backcrosses and on the Deli origin of E. guineensis. Development at the second- and third- larval instars was the most affected, with a mortality rate of three to five times greater than that seen on La Mé. Epidermis and cuticle measurements indicated which breeding populations were suitable or unsuitable for the development of C. lameensis. E. guineensis, with its thin epidermis (12 µm) and cuticle (2 µm), proved to be highly susceptible to C. lameensis attacks. On the other hand, E. oleifera, which is very resistant, exhibited a thicker epidermis (17 µm) and cuticle (4 µm). The breeding populations were thus classified according to the positive or negative influence they exerted on the insect’s egg laying and feeding.RÉSUMÉ. La comestibilité de différents matériels végétaux d’Elaeis sp. présents au Bénin est testée pour Coelaenomenodera lameensis Berti (Coleoptera: Chrysomelidae), important ravageur du palmier à huile en Afrique. Des expérimentations en manchons ont permis de déterminer les capacités d’oviposition des femelles et les taux de mortalité des différents stades de développement (œufs, larves, nymphes et adultes) en comparant les populations observées sur deux origines d’Elaeis oleifera (HBK) Cortes, quatre origines d’Elaeis guineensis Jacquin et quatre Backcross (E. guineensis × E. oleifera) × E. guineensis. Les femelles pondent indifféremment sur tous les types de matériel végétal avec une préférence pour l’origine La Mé d’E. guineensis. Le taux moyen d’éclosion atteint 80% pour l’origine La Mé contre 28% pour l’origine Deli. Le taux de mortalité des stades larvaires est plus important sur E. oleifera, sur certains Backcross et sur l’origine Deli d’E. guineensis. Le développement des deuxième et troisième stades larvaires sont les plus affectés avec un taux de mortalité 3 à 5 fois supérieur à celui observé sur La Mé. Des mesures d’épiderme et de cuticule mettent en évidence l’existence de matériel végétal favorable ou défavorable au développement de C. lameensis. E. guineensis dont l’épiderme (12 µm) et la cuticule (2 µm) sont peu épais se révèle être très sensible aux attaques de C. lameensis. Au contraire, E. oleifera présente un épiderme (17 µm) et une cuticule (4 µm) plus épais et est très résistants. Le matériel végétal est ainsi classé suivant l’influence positive ou négative qu’ils exercent sur la ponte et l’alimentation des insectes.     

Expression and Characterization of a Novel Cold-Adapted and Stable β-Agarase Gene agaW1540 from the Deep-Sea Bacterium Shewanella sp. WPAGA9

The neoagaro-oligosaccharides, degraded from agarose by agarases, are important natural substances with many bioactivities. In this study, a novel agarase gene, agaW1540, from the genome of a deep-sea bacterium Shewanella sp. WPAGA9, was expressed, and the recombinant AgaW1540 (rAgaW1540) displayed the maximum activity under the optimal pH and temperature of 7.0 and 35 °C, respectively. rAgaW1540 retained 85.4% of its maximum activity at 0 °C and retained more than 92% of its maximum activity at the temperature range of 20–40 °C and the pH range of 4.0–9.0, respectively, indicating its extensive working temperature and pH values. The activity of rAgaW1540 was dramatically suppressed by Cu²⁺ and Zn²⁺, whereas Fe²⁺ displayed an intensification of enzymatic activity. The K_m and V_max of rAgaW1540 for agarose degradation were 15.7 mg/mL and 23.4 U/mg, respectively. rAgaW1540 retained 94.7%, 97.9%, and 42.4% of its maximum activity after incubation at 20 °C, 25 °C, and 30 °C for 60 min, respectively. Thin-layer chromatography and ion chromatography analyses verified that rAgaW1540 is an endo-acting β-agarase that degrades agarose into neoagarotetraose and neoagarohexaose as the main products. The wide variety of working conditions and stable activity at room temperatures make rAgaW1540an appropriate bio-tool for further industrial production of neoagaro-oligosaccharides.     

Chemical Composition,Antifeedant, Repellent,and Toxicity Activities of the Rhizomes of Galangal,Alpinia galanga Against Asian Subterranean Termites,Coptotermes gestroi and Coptotermes curvignathus (Isoptera: Rhinotermitidae)

Dual choice bioassays were used to evaluate the antifeedant property of essential oil and methanolic extract of Alpinia galanga (L.) (locally known as lengkuas) against two species of termites, Coptotermes gestroi (Wasmann) and Coptotermes curvignathus (Holmgren) (Isoptera: Rhinotermitidae). A 4-cm-diameter paper disc treated with A. galanga essential oil and another treated with either methanol or hexane as control were placed in a petri dish with 10 termites. Mean consumption of paper discs (miligram) treated with 2,000 ppm of essential oil by C. gestroi was 3.30 ± 0.24 mg and by C. curvignathus was 3.32 ± 0.24 mg. A. galanga essential oil showed significant difference in antifeedant effect, 2,000 ppm of A. galanga essential oil was considered to be the optimum concentration that gave maximum antifeedant effect. The essential oil composition was determined using gas chromatography-mass spectrometry. The major component of the essential oil was 1,8-cineol (61.9%). Antifeedant bioassay using 500 ppm of 1,8-cineol showed significant reduction in paper consumption by both termite species. Thus, the bioactive agent in A. galangal essential oil causing antifeeding activity was identified as 1,8-cineol. Repellent activity shows that 250 ppm of 1,8-cineol caused 50.00 ± 4.47% repellency for C. gestroi, whereas for C. curvignathus 750 ppm of 1,8-cineol was needed to cause similar repellent activity (56.67 ± 3.33%). C. curvignathus is more susceptible compare to C. gestroi in Contact Toxicity study, the lethal dose (LD₅₀) of C. curvignathus was 945 mg/kg, whereas LD₅₀ value for C. gestroi was 1,102 mg/kg. Hence 1,8-cineol may be developed as an alternative control against termite in sustainable agriculture practices.     

Geographic Variation of Diapause and Sensitive Stages of Photoperiodic Response in Laodelphax striatellus Fallén (Hemiptera: Delphacidae)

Large numbers of the small brown planthopper Laodelphax striatellus (Fallén) (Hemiptera: Delphacidae) occur in temperate regions, causing severe losses in rice, wheat, and other economically important crops. The planthoppers enter diapause in the third- or fourth-instar nymph stage, induced by short photoperiods and low temperatures. To investigate the geographic variation in L. striatellus diapause, we compared the incidence of nymphal diapause under various constant temperature (20 and 27°C) and a photoperiod of 4:20, 8:16, 10:14, 12:12, 14:10, and 16:8 (L:D) h regimes among three populations collected from Hanoi (21.02° N, 105.85° E, northern Vietnam), Jiangyan (32.51° N, 120.15° E, eastern China), and Changchun (43.89° N, 125.32° E, north-eastern China). Our results indicated that there were significant geographic variations in the diapause of L. striatellus. When the original latitude of the populations increased, higher diapause incidence and longer critical photoperiod (CP) were exhibited. The CPs of the Jiangyan and Changchun populations were ∼12 hr 30 min and 13 hr at 20°C, and 11 hr and 11 hr 20 min at 27°C, respectively. The second- and third-instar nymphs were at the stage most sensitive to the photoperiod. However, when the fourth- and fifth-instar nymphs were transferred to a long photoperiod, the diapause-inducing effect of the short photoperiod on young instars was almost reversed. The considerable geographic variations in the nymphal diapause of L. striatellus reflect their adaptation in response to a variable environment and provide insights to develop effective pest management strategies.     

Developmental Biology of Zeugodacus cucurbitae (Diptera: Tephritidae) in Three Cucurbitaceous Hosts at Different Temperature Regimes

Fruit flies are key pests of cucurbits in many parts of the world, including Tanzania. Developmental biology of Zeugodacus cucurbitae (Coquillett) has been determined across temperature regimes in some cucurbitaceous hosts, in limited geographies. This study was conducted to determine duration and survival rates of immature stages of Z. cucurbitae in three cucurbitaceous hosts, at different temperature regimes. It was hypothesized that temperature and cucurbitaceous hosts influence duration and survival of immature stages of Z. cucurbitae. We conducted experiments in the environmental chamber set at 75 ± 10% RH and a photoperiod of 12:12 (L:D) h, at temperatures of 20, 25, and 30°. Our results showed that duration and survival of immature stages of Z. cucurbitae differed significantly among the temperature regimes but not among the hosts. Egg incubation period as well as larval and pupal stages were significantly longer (P < 0.0001) at low temperature in all three hosts Likewise, survival rate of all immature stages were significantly higher (P < 0.0001) at higher than lower temperatures. The three hosts, cucumber (Cucumis sativus), watermelon (Citrullus lanatus (Thunb.) Matsum. and Nakai), and pumpkin (Cucurbita pepo) did not significantly affect duration or survival rates of immature stages of Z. cucurbitae. The low developmental thresholds were estimated at 15.88, 13.44, and 12.62 for egg, larva and pupa, respectively. These results further confirm that Z. cucurbitae is well adapted to warm climate, which dominates many areas of Tanzania.     

Characterization of Neoagarooligosaccharide Hydrolase BpGH117 from a Human Gut Bacterium Bacteroides plebeius

α-Neoagarobiose (NAB)/neoagarooligosaccharide (NAO) hydrolase plays an important role as an exo-acting 3,6-anhydro-α-(1,3)-L-galactosidase in agarose utilization. Agarose is an abundant polysaccharide found in red seaweeds, comprising 3,6-anhydro-L-galactose (AHG) and D-galactose residues. Unlike agarose degradation, which has been reported in marine microbes, recent metagenomic analysis of Bacteroides plebeius, a human gut bacterium, revealed the presence of genes encoding enzymes involved in agarose degradation, including α-NAB/NAO hydrolase. Among the agarolytic enzymes, BpGH117 has been partially characterized. Here, we characterized the exo-acting α-NAB/NAO hydrolase BpGH117, originating from B. plebeius. The optimal temperature and pH for His-tagged BpGH117 activity were 35 °C and 9.0, respectively, indicative of its unique origin. His-tagged BpGH117 was thermostable up to 35 °C, and the enzyme activity was maintained at 80% of the initial activity at a pre-incubation temperature of 40 °C for 120 min. K_m and V_max values for NAB were 30.22 mM and 54.84 U/mg, respectively, and k_cat/K_m was 2.65 s⁻¹ mM⁻¹. These results suggest that His-tagged BpGH117 can be used for producing bioactive products such as AHG and agarotriose from agarose efficiently.     

Comparative Feeding Performance and Digestive Physiology of Helicoverpa armigera (Lepidoptera: Noctuidae) Larvae-Fed 11 Corn Hybrids

This study aimed to evaluate the feeding responses and digestive proteolytic and amylolytic activity of Helicoverpa armigera (Hübner) on 11 corn (Zea mays L.) hybrids at 25 ± 1°C, 65 ± 5% relative humidity (RH), and a photoperiod of 16:8 (L:D) h. The fourth- and fifth-instar larvae fed on hybrid K47*K19 had the highest weight of food consumption and those reared on hybrid KSC705 had the lowest value of food consumption. The highest weight gain of the larvae was observed when H. armigera were fed hybrid KLM78*MO17 and lowest when they were fed hybrids K36 * MO17, KSC705, and K35 * K36. Pupal weight of H. armigera was heaviest when larvae were fed hybrid K47*K19 and lightest when they were fed hybrid KSC705. The highest proteolytic activity of the fourth-instar larvae was observed when they were fed hybrid KSC705, and the lowest activity was observed when they were fed hybrid K47*A67. Fifth-instar larvae that fed on hybrid K47*K19 showed the highest proteolytic activity. Fourth-instar larvae that fed on hybrid K36*MO17 showed the highest amylase activity. The fifth-instar larvae fed on hybrid K47*A67 showed the maximum amylase activity and those reared on the K48*K18 showed the minimum activity. Our results indicated that K36 * MO17, KSC705, and K48 * K18 were the most unsuitable hybrids for feeding H. armigera.     

Influence of Temperature on Growth and Production of Pectenotoxin-2 by a Monoclonal Culture of Dinophysis caudata

The effects of temperature on growth and production of Lipophilic Toxins (LT) by a monoclonal culture of Dinophysis caudata was studied. The cell density of D. caudata increased significantly with increasing temperature, and was the highest under 27, 30, and 32.5 °C. Temperature affected the average specific growth rate (µ) during the exponential growth phase (EG), which increased from 15 °C to 30 °C, and then decreased at 32.5 °C. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) revealed that this strain of D. caudata produced only pectenotoxin-2 (PTX-2) whose concentration increased significantly with incubation period, except at 32.5 °C. It was significantly different between temperatures ≤18 °C, ≥21 °C, and 32.5 °C. The cellular toxin production (CTP, pg·cell⁻¹·day⁻¹) showed variation with growth phase and temperature, except at 32.5 °C. The average net toxin production (R_tox) was not affected by temperature. During EG, the average specific toxin production rate (µ_tox) increased significantly with increase in temperature, reaching a peak of 0.66 ± 0.01 day⁻¹ at 30 °C, and then decreased. Over the entire growth span, µ_tox was significantly correlated to µ, and this correlation was most significant at 27 and 30 °C. During EG, µ_tox was affected by both temperature and growth. This study shows that temperature affects growth and toxin production of this strain of D. caudata during EG. In addition, a positive correlation was found between toxin production and growth.     

The Effect of Chemical Composition and Bioactivity of Several Essential Oils on Tenebrio molitor (Coleoptera: Tenebrionidae)

The major chemical components of four essential oils (EOs) extracted from dry leaves of Citrus limonum, Cymbopogon citratus, Litsea cubeba, and Muristica fragrans were analyzed with gas chromatograph-mass spectrometer and their fumigant, contact, and repellent activities against 10th instar and adults of Tenebrio molitor were also assayed. The results indicated that the major constituents of C. limonum and Cy. citrates were D-limonene (38.22%) and 3,7-dimethyl-6-octenal (26.21%), while which of L. cubeba and M. fragrans were (E)-3, 7-dimethyl-2, 6-octadienal (49.78%) and (E)-cinnamaldehyde (79.31%), respectively. Contact activities of L. cubeba and C. limonum with LC₅₀ values of 21.2 and 13.9 µg/cm² at 48 h and repellence activities (>89.0% repellence indexes) (P < 0.05) at 12 h on 10th instar were better than those of the other two EOs. Nevertheless, the fumigation activities of L. cubeba on 10th instar and adults (LC₅₀ = 2.7, 3.7 μl/liter) were stronger than those of C. limonum (LC₅₀ = 10.9, 12.0 μl/liter) at 96 h and significant (not overlapping confidence intervals). The EOs of L. cubeba and C. limonum have clearly elongated the growth and development of larvae, egg, and slightly shorten pupae and adults of T. molitor compared with the control. The mainly active ingredients of L. cubeba and C. limonum, including D-limonene and β-pinene, were demonstrated to coinhibit the actives of AChE and enhance the toxicities on 10th instar of T. molitor. These results indicate that the EOs of L. cubeba and C. limonum could have great potential as botanical insecticides against T. molitor.     

Isolation,Characterization, Kinetics,and Enzymatic and Nonenzymatic Microbicidal Activities of a Novel c-Type Lysozyme from Plasma of Schistocerca gregaria (Orthoptera: Acrididae)

A protein, designated as Sgl, showing a muramidase lytic activity to the cell wall of the Gram-positive bacterium Micrococcus lysodeikticus was isolated for the first time from plasma of Escherichia coli-immunized fifth instar Schistocerca gregaria. The isolated Sgl was detected as a single protein band, on both native- and SDS-PAGE, has a molecular weight of ∼15.7 kDa and an isoelectric point (pI) of ca 9.3 and its antiserum has specifically recognized its isolated form. Fifty-nine percentage of Sgl lytic activity was recovered in the isolated fractions and yielded ca 126-fold increase in specific activity than that of the crude. The partial N-terminal amino acid sequence of the Sgl has 55 and 40% maximum identity with Bombyx mori and Gallus gallus c-type lysozymes, respectively. The antibacterial activity against the Gram-positive and the Gram-negative bacteria were comparatively stronger than that of the hen egg white lysozyme (HEWL). The detected Sgl poration to the inner membrane that reach a maximum ability after 3 h was suggested to operate as a nonenzymatic mechanism for Gram-negative bacterial cell lysis, as tested in a permease-deficient E. coli, ML-35 strain. Sgl showed a maximal muramidase activity at pH 6.2, 30–50°C, and 0.05 M Ca²⁺ or Mg²⁺; and has a K_m of 0.5 μg/ml and a V_max of 0.518 with M. lysodeikticus as a substrate. The Sgl displayed a chitinase activity against chitin with a K_m of 0.93 mg/ml and a V_max of 1.63.     

Preparation and Characterization of Thermally Stable Collagens from the Scales of Lizardfish (Synodus macrops)

Marine collagen is gaining vast interest because of its high biocompatibility and lack of religious and social restrictions compared with collagen from terrestrial sources. In this study, lizardfish (Synodus macrops) scales were used to isolate acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC). Both ASC and PSC were identified as type I collagen with intact triple-helix structures by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and spectroscopy. The ASC and PSC had high amino acids of 237 residues/1000 residues and 236 residues/1000 residues, respectively. Thus, the maximum transition temperature (T_max) of ASC (43.2 °C) was higher than that of PSC (42.5 °C). Interestingly, the T_max of both ASC and PSC was higher than that of rat tail collagen (39.4 °C) and calf skin collagen (35.0 °C), the terrestrial collagen. Solubility tests showed that both ASC and PSC exhibited high solubility in the acidic pH ranges. ASC was less susceptible to the “salting out” effect compared with PSC. Both collagen types were nontoxic to HaCaT and MC3T3-E1 cells, and ASC was associated with a higher cell viability than PSC. These results indicated that ASC from lizardfish scales could be an alternative to terrestrial sources of collagen, with potential for biomedical applications.     

Potential of two entomopathogenic fungi,Beauveria bassiana and Metarhizium anisopliae (Coleoptera: Scarabaeidae), as biological control agents against the June beetle

The aim of this study was to evaluate the effectiveness of the entomopathogenic fungi (EPF), Beauveria bassiana (Bals.) Vuill. (Deuteromycotina: Hyphomycetes) strain PPRI 5339 [BroadBand, an emulsifiable spore concentrate (EC) formulation] and Metarhizium anisopliae (Metsch.) Sorokin (Hypocreales: Clavicipitaceae) strain F52 [Met52, both EC and granular (GR) formulations] against the larvae of Polyphylla fullo (L.) (Coleoptera: Scarabaeidae). Larvicidal bioassays were performed in foam boxes (100 by 75 by 50 cm; length by width by height), containing moist soil medium with some humus and potato tubers as food. Although the B. bassiana product (min. 4 × 10⁹ conidia/ml) was applied at 100, 150, and 200 ml/100 l water; M. anisopliae strain F52 was applied at 500, 1,000, and 1,500 g/m³ of moist soil medium for GR (9 × 10⁸ cfu/g) and 75, 100, and 125 ml/100 l water for EC (5.5 × 10⁹ conidia/ml) formulation. Both fungi were pathogenic to larvae of the pest; however, young larvae (1st and 2nd instars) were more susceptible to infection than older ones (3rd instar). Mortality rates of young and older larvae varied with conidial concentration of both fungi and elapsed time after application. The B. bassiana product was more effective than both of the formulations of the M. anisopliae product, causing mortalities up to 79.8 and 71.6% in young and older larvae, respectively. The highest mortality rates of young and older larvae caused by the M. anisopliae product were 74.1 and 67.6% for the GR formulation, 70.2 and 61.8% for the EC formulation, respectively. These results may suggest that both fungi have potential to be used for management of P. fullo.     

Adult Behavior of Tirumala limniace (Lepidoptera: Danaidae)

Tirumala limniace Cramer as an ornamental butterfly is utilized in butterfly garden, in this article we study their adult activities include flight, foraging, courtship, mating, and oviposition. We found that males spent 22.1% of its time flying, 14.1% foraging, 63.8% in courtship and mating. And females spent 30.8% of its time flying, 10.1% foraging, 57.1% in courtship and mating, and 2% ovipositing. Adults emerged from pupae when temperatures were above 23.5°C and eclosion took only ∼1 min, typically followed by a small amount of flight on the first day. Flight activity peaked from the ninth to the thirteenth day after eclosion, and there were two daily peak flight times: 10:00–13:00 and 15:00–18:00. The peak of flower-visiting activity was from the eighth to the thirteenth day after eclosion, and there were two daily peak foraging times: 11:00–12:00 and 16:00–17:00. Flight and foraging frequency and time were positively correlated and both were closely related to temperature, with very little flight or foraging below 18°C and an increase at temperatures above 22°C. Courtship and mating took place on the sixth day after eclosion, while oviposition occurred the following day. Oviposition occurred over 8 d, and the shortest time of a single oviposition was 2 s. The average life expectancy of males was 16.5 d, while that of females was 15 d.     

Demographic Parameters of Nezara viridula (Heteroptera: Pentatomidae) Reared on Two Diets Developed for Lygus spp.

Two artificial diets developed for rearing Lygus spp., a fresh yolk chicken egg based-diet (FYD) and a dry yolk chicken egg based-diet (DYD), were evaluated as an alternative food source for rearing the southern green stink bug, Nezara viridula (L.) (Heteroptera: Pentatomidae). Survival to adult was 97.3 and 74.67%, respectively, on the fresh and dry yolk diets. Insects fed FYD had 100% survival of nymphs from first through fourth instars. Adult development was significantly shorter on FYD (30.37 ± SE 0.30 d) as compared with DYD (32.77 ± SE 0.16 d). Increased male and female longevity, higher fecundity, and larger egg mass sizes were also observed with N. viridula-fed FYD. However, fertility and hatchability was higher on DYD. A complete cohort life table was constructed to describe the development of N. viridula on both diets.     

Stability of Domoic Acid in 50% Methanol Extracts and Raw Fecal Material from Bowhead Whales (Balaena mysticetus)

Domoic acid (DA), the toxin causing amnesic shellfish poisoning (ASP), is produced globally by some diatoms in the genus Pseudo-nitzschia. DA has been detected in several marine mammal species in the Alaskan Arctic, raising health concerns for marine mammals and subsistence communities dependent upon them. Gastrointestinal matrices are routinely used to detect Harmful Algal Bloom (HAB) toxin presence in marine mammals, yet DA stability has only been studied extensively in shellfish-related matrices. To address this knowledge gap, we quantified DA in bowhead whale fecal samples at multiple time points for two groups: (1) 50% methanol extracts from feces, and (2) raw feces stored in several conditions. DA concentrations decreased to 70 ± 7.1% of time zero (T₀) in the 50% methanol extracts after 2 weeks, but remained steady until the final time point at 5 weeks (66 ± 5.7% T₀). In contrast, DA concentrations were stable or increased in raw fecal material after 8 weeks of freezer storage (−20 °C), at room temperature (RT) in the dark, or refrigerated at 1 °C. DA concentrations in raw feces stored in an incubator (37 °C) or at RT in the light decreased to 77 ± 2.8% and 90 ± 15.0% T₀ at 8 weeks, respectively. Evaporation during storage of raw fecal material is a likely cause of the increased DA concentrations observed over time with the highest increase to 126 ± 7.6% T₀ after 3.2 years of frozen storage. These results provide valuable information for developing appropriate sample storage procedures for marine mammal fecal samples.