Biological control of aflatoxigenic fungi on peanut: For the pre-harvest approach

This study was carried out to determine the efficacy of different applications of a biopesticide for reduction of aflatoxin contamination in peanut. The biopesticide, afla-guard, delivers a nontoxigenic Aspergillus flavus to the field where it competes with naturally occurring toxigenic fungus. Biocontrol treatments included: (ı) soil application during sowing, (ıı) multiple application during sowing and 40 days after planting, (ııı) foliar application at 60 days after planting (ıv) control (untreated plots). Biopesiticide was applied to peanut plots in 2015 and 2016 in Randomized Complete Block Design with four replications. Peanuts were collected from control and treated plots at harvest-drying-pre-storage periods and analysed for aflatoxins. Aflatoxin concentrations were generally quite low in 2015, also the aflatoxin concentration in treated samples (from 0.04 to 0.71 µg/kg) was reduced by 97.38 to 99.82% compared with controls (from 21.84 to 27.12 µg/kg). In 2016, reductions were also noted for all biocontrol treatments (from 89.07 to 92.39%) compared with controls. In conjunction with the reductions in aflatoxin contamination, biocontrol treatments produced significant reductions with biopesticide in peanut. Therefore, it can be said that a biological control method is a promising approach for controlling aflatoxin. © 2019, Society of Field Crops Science. All rights reserved.This study (Project No 115O007) was financial supported by The Scientific Technological Research Council of Turkey (TUBITAK)

Conducting multiphase block copolymers of polypyrrole with polytetrahydrofuran and polytetrahydrofuran-b-polystyrene

Living bifunctional azo-polytetrahydrofuran (azo-PTHF) was terminated with pyrrolyl potassium salt to yield a polymer with electrochemically active functional end groups. This polymer is further used to synthesize polytetrahydrofuran-polystyrene (PTHF-b-PS-b-PTHF) block copolymer. These polymers are electrochemically blocked with polypyrrole using constant potential electrolysis (PPy/Azo-PTHF and PPy/PTHF-b-PS-b-PTHF). Two different solvent-electrolyte pairs were used during electrolysis. Characterizations of pristine and the blocked copolpolymers are based on Cyclic Voltammetry (CV), Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Thermal Gravimetry Analysis (TGA), Scanning Electron Microscope (SEM) Nuclear Magnetic Resonance Spectroscopy (NMR) and Gel Permeation Chromatography (GPC). Conductivities were measured using a four-probe technique

Esterase variation and some biological characteristics of two Turkish Trichogramma (Hymenoptera: Trichogrammatidae) populations

Abstract. In this study, esterase variation was investigated for one Trichogramma turkestanica Meyer and two Trichogramma brassicae Bezdenko populations collected from Southeast Turkey. Depending on the banding patterns there were slower (Est1) and faster (Est2) bands as two different isozymes were determined. T. turkestanica had a different banding pattern than T. brassicae. At the same time, numbers of parasitized eggs and female and male offspring, and adult longevity were determined for each population. There were no significant differences between cultures except adult longevity. Some morphometric characters of cultures were also measured, comprising body length, flagellum length, head width, the longest seta of the flagellum, hind tibia and hind wing length. All characters were similar between the two T. brassicae populations and were significantly different from T. turkestanica

A molecular key to the common species of Trichogramma of the Mediterranean region

A molecular key for the identification of common Trichogramma (Hymenoptera: Trichogrammatidae) species found in agricultural settings around the Mediterranean is developed based on the sequence of the internal transcribed spacer 2 of the ribosomal cistron. Using the size of the ITS2 PCR product and restriction fragment length polymorphisms of the amplicon, ten Trichogramma species (T. bourarachae Pintureau and Babault, T. brassicae Bezdenko, T. cacoeciae Marchal/T. embryophagum Hartig, T. cordubensis Vargas and Cabello, T. dendrolimi Matsumura, T. euproctidis Girault, T. evanescens Westwood, T. nerudai Pintureau and Gerding, T. oleae Voegelé and Pointel, and T. pintoi Voegelé) can be distinguished