Old and new host-parasitoid associations: parasitism of the invasive fruit fly Bactrocera invadens (Diptera: Tephritidae) and five African fruit fly species by Fopius arisanus,an Asian opiine parasitoid

Fopius arisanus (Sonan), a solitary koinobiont endoparasitoid of fruit flies, was introduced for testing and final release against the recently discovered species Bactrocera invadens Drew, Tsuruta and White in Africa. Laboratory experiments were conducted to assess host preference, host acceptability for oviposition, and physiological suitability of B. invadens and five other indigenous tephritid fruit fly species, namely, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), C. cosyra (Walker), C. rosa Karsch, C. fasciventris (Bezzi), and C. anonae Graham. Females of F. arisanus visited all host egg patches, but showed a stronger preference to eggs of B. invadens, which was also most accepted for oviposition. Successful development of parasitoid progenies varied greatly across hosts, with B. invadens yielding the highest parasitoid progeny and C. fasciventris yielding no F. arisanus progeny. Most of the parasitoid eggs laid in C. rosa and C. fasciventris were encapsulated. Sex ratio was not influenced by host species and it was female biased in all hosts that produced parasitoid progeny. Fopius arisanus was able to establish a new association with C. capitata, C. cosyra and to a lesser extent C. anonae. The results are discussed in the light of the potential use of F. arisanus as a biological control agent of B. invadens.     

Vasopressin analog (DDAVP) facilitates concept learning in human males

The effects of desmopressin acetate (DDAVP) were studied in normal males. Subjects were given 60μg of DDAVP, a placebo, or no treatment and were given several behavioral tests. DDAVP enhanced learning of all problems on a concept shift task but had no effect on visual memory, anxiety, blood pressure or heart rate. It was suggested that DDAVP may influence memory via its actions on attention.     

Laboratory studies on the biology of the corn leaf aphid, Rhopalosiphum maidis (Homoptera: Aphididae)

The biology of R. maidis has been shown to be affected considerably by the temperature, the host plant, and the physiological age of food plant. The optimum temperature was 30°C; here nymphal development was accelerated, the whole life-span was drastically shortened to less than half that at 15°, and natality rate/surviving female was increased with rather negligible deaths among progeny. Barley was the most favourable host studied under the specified experimental conditions, and young plants (3–5 days old) represented the best stage of plant growth. R. maidis may have about 50 generations/year when aphids were kept feeding continuously on 5-day old barley plants but this does, by no means, represent the actual number of generations under field conditions; it only indicates that almost half of these may be restricted to the summertime.

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Résumé La présente étude montre que la température, ainsi que l'espèce de la plante hôte et son âge physiologique influencent grandement la biologie de Rhopalosiphum maïdis.Quand ce puceron est élevé sur des pousses d'orge âgées de 5 jours, la température optimum est de 30°. Dans ces conditions, la maturation peut être acquise en un délai aussi court que 4,6 jours, tandis que la longévité est réduite à 16,8±1,3 jours contre 35,1±5,1 jours à 15°. Enfin, la natalité par femelle et par jour est accrue avec un taux de mortalité négligeable parmi la descendance.De quatre plantes testées, (orge, mil, fève et maïs) au même âge de croissance (7 jours) l'orge est le plus favorable. Rhopalosiphum maïdis peut avoir environ 50 générations par an quand il est élevé de façon continue sur des plants d'orge âgés de 5 jours; cela ne signifie pas que dans les conditions naturelles il en est ainsi, mais indique que presque la moitié de ce nombre de générations peut intervenir pendant l'été.

     

Characterization of Lead in Soils of a Rifle/Pistol Shooting Range in Central Florida,USA

The distribution of lead in soil samples collected from both surface (0 to 10?cm) and profile (O 0 to 10?cm, E 11 to 30?cm, Eb 31 to 50?cm, Bw 51 to 100?cm, and C 181 to 200?cm) at a 14-year-old rifle/pistol shooting range located in central Florida were determined using EPA Method 3051a (microwave, HNO₃/HCl=3:1, v/v). In addition to total lead analysis, Toxicity Characteristic Leaching Procedure (TCLP) analysis was performed on corresponding samples to determine whether the soils would require special handling as hazardous waste if the soils were to be removed from the range. Total lead in surface soils varied from 330 to 17 850?mg Pb kg^?1, with the greatest concentration in the middle of the backstop berm. The TCLP tests indicated that lead in all surface soils exceeded the 5?mg Pb L^?1 critical level of federal regulation for solid wastes and hazardous wastes provided by the Resource Conservation and Recovery Act (RCRA) and would be characterized as hazardous waste. Sequential fractionation and X-ray diffraction (XRD) analyses revealed that lead carbonate existed predominantly (91.3%) in the berm soil. The weathering of lead bullets in the soil environments formed primarily as hydrocerussite (Pb₃(CO₃)₂(OH)₂), with small amounts of massicot (PbO) and cerussite (PbCO₃). However, the elevated soil pH, caused by the oxidization and transformation process of elemental lead in lead bullets, could be a significant factor in limiting the migration of lead in the soil.     

An in-house real-time polymerase chain reaction: standardisation and comparison with the Cobas Amplicor HBV monitor and Cobas AmpliPrep/Cobas TaqMan HBV tests for the quantification of hepatitis B virus DNA

This study aimed to standardise an in-house real-time polymerase chain reaction (rtPCR) to allow quantification of hepatitis B virus (HBV) DNA in serum or plasma samples, and to compare this method with two commercial assays, the Cobas Amplicor HBV monitor and the Cobas AmpliPrep/Cobas TaqMan HBV test. Samples from 397 patients from the state of São Paulo were analysed by all three methods. Fifty-two samples were from patients who were human immunodeficiency virus and hepatitis C virus positive, but HBV negative. Genotypes were characterised, and the viral load was measure in each sample. The in-house rtPCR showed an excellent success rate compared with commercial tests; inter-assay and intra-assay coefficients correlated with commercial tests (r = 0.96 and r = 0.913, p < 0.001) and the in-house test showed no genotype-dependent differences in detection and quantification rates. The in-house assay tested in this study could be used for screening and quantifying HBV DNA in order to monitor patients during therapy.     

Bio-ecology of false codling moth,Thaumatotibia leucotreta (Meyrick) (Lepidoptera: Tortricidae) within citrus orchards in Kenya and Tanzania

1. False codling moth, Thaumatotibia leucotreta is among the key constraints of the agricultural industry. Little is known about the population dynamics and genetic diversity of this pest in East Africa.
2. The spatial–temporal population dynamics and genetic diversity of false codling moth were evaluated in citrus orchards in Kenya and Tanzania between May 2017 and August 2018 covering two fruiting seasons. The diversity of false codling moth sampled in these orchards and from solanaceous hosts, as well as from specimens received from Uganda, Sudan, and South Africa were assayed using the mitochondrial cytochrome oxidase I gene.
3. A similar spatial–temporal pattern of false codling moth was found in both Kenya and Tanzania, with the most male moths in August 2017 and 2018. In Tanzania, the number of male moths caught at high and mid altitudes did not differ but were significantly higher than those caught at low altitude.
4. A relatively low false codling moth genetic diversity was recorded at the sites where sampling was done in the respective countries as well as between specimens sampled from different host plants.
5. The low false codling moth genetic diversity determined in this trial can be exploited in the management of the pest in the studied countries.

     

Evaluating the Potential of Halothiobacillus Bacteria for Sulfur Oxidation and Biomass Production under Saline Soil

Abstract

Salinity negatively affects growth of sulfur-oxidizing bacteria (SOB) and their sulfate production ability, meanwhile decreases the available sulfate for plants in soil. The aim of this study was to isolate and characterize the bacteria of genus Halothiobacillus, as a salt-tolerant SOB, from saline and sulfidic habitats of Iran for the first time and evaluating the effect of salinity on their biomass and sulfate production during the oxidation of different sulfur sources. Isolation process and surveying the morphological, biochemical and 16S rRNA gene analysis resulted into identification of three species (eight strains) of Halothiobacillus genus including H. neapolitanus, H. hydrothermalis and H. halophilus. Salinity (0, 0.5, 1, 2 and 4?M NaCl) had a significant impact (p?≤?0.01) on bacterial biomass and sulfate production during the oxidation of thiosulfate and elemental sulfur. Biomass and sulfate production by strains was accompanied by a decrease in residual content of thiosulfate (RCT) in medium. The amount of produced biomass and sulfate in medium supplemented by thiosulfate was much higher than elemental sulfur. The highest amount of biomass and sulfate was produced by H. neapolitanus strain I19 at 0.5 and 1?M NaCl concentration. The results of this study could be the first step to focus on the application of these bacteria to increase sulfate storage of saline soils and crop production.     

The Relationship Between Maternal Serum Iron and Zinc Levels and Their Nutritional Intakes in Early Pregnancy with Gestational Diabetes

The aim of this study was to investigate the association between maternal iron/zinc serum levels and their nutritional intake in early pregnancy with gestational diabetes. The maternal serum zinc/iron levels were measured in 1,033 healthy singleton pregnant women aged 20–35 between 14 and 20 weeks of gestation, within two groups: namely, normal and gestational diabetes, and participants were followed up to 24–28 weeks of gestation. Food frequency questionnaire was used to assess nutritional intakes of iron/zinc. The main outcome was gestational diabetes screened with the 50-g glucose challenge test and diagnosed with oral glucose tolerance test at 24–28 weeks of gestation. Gestational diabetes occurred in 72 (6.96 %) of 1,033 women in study. There was a statistical relationship between early pregnancy maternal serum iron and gestational diabetes, mean (SD), 143.8 (48.7) vs. 112.5 (83.5)?μg/dl, P value of <0.0001. There was no statistical significant difference in zinc levels and iron/zinc nutritional intake between groups. The results remained unchanged after using regression model for adjustment of potential risk factors with an adjusted OR of 1.006 (95 % CI 1.002 to 1.009; P?=?0.001) for early pregnancy maternal serum iron to cause gestational diabetes. The receiver–operator characteristic curve identified that a maternal serum iron above 100 μg/dl in early pregnancy is the optimum cutoff value for predicting gestational diabetes, which showed a sensitivity and specificity of 80.6 and 50.7 %, respectively. In conclusion, high maternal serum iron in early pregnancy could increase the risk of gestational diabetes. Also, it could be used as a sensitive and specific predictor for gestational diabetes.