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Aphids are one of the major insect pests of greenhouses and field crops worldwide. Several species of entomopathogenic fungi (EPF), including Lecanicillium spp. Beauveria bassiana, Isaria fumosorosea and Metarhizium anisopliae, have been developed commercially to control aphid species. However, there are no commercial products based on EPF that have been registered in Iraq. This study, therefore, was conducted to evaluate the virulence of four isolates of EPF, including, B. bassiana, Lecanicillium lecanii, M. anisopliae and Chaetomium globosum to select the highly virulent ones against the greenhouse aphids. Although the isolate of L. lecanii had the highest virulence against all tested aphid species in the laboratory bioassay, Myzus persicae Sulz and Aphis gossypii Gloy were more susceptible than Aphis fabae and Macrosiphum euphorbiae to infection with L. lecanii. Mortality caused by L. lecanii 7 days post-treatment with 10 8 conidia ml −1 was 100%. Further experiments in the greenhouses showed that L. lecanii significantly reduced the density of both M. persicae and A. gossypii 5 days after fungal applications. This isolate shows a promise for development of an alternative control agent against M. persicae and A. gossypii in Iraq.

This study was conducted to isolate and identify three isolates of Tomato yellow leaf curl virus (TYLCV), infecting tomato, using polymerase chain reaction technology (PCR) and determining the nucleotide sequences produced by PCR- amplified products to determine the genetic similarity and differences amongst the virus isolates. It also aimed to analyze the plant content of mineral elements: magnesium, calcium, sodium, and potassium to determine the effect of the virus on the plant content of these elements. The laboratory experiments mentioned in this study were carried out in the Plant Virology Laboratory of the Plant Protection Department at the College of Agriculture/ Karbala University. Analysis of the mineral elements was carried out in the Soil Laboratory, College of Agriculture/ University of Kufa. A greenhouse experiment was also carried out to investigate the response of some tomato genotypes against TYLCV during the agricultural season 2018-2019. Results of PCR amplification by the CP-F and CP-R primer pair revealed the possibility of amplifying a 789bp product from each TYLCV isolate isolated from some farms located in some desert areas in Najaf and Karbala governorates. Analysis of the sequences resulting from the PCR-amplified products obtained from the viral isolates (5, 8, and 10) by BLAST Basic Local Alignment Search Tool (BLAST) indicated that all these viral isolates diagnosed in this study belong to TYLCV. TYLCV isolates 5 and 8 obtained from Najaf province had a 100% similarity in the sequences of PCR-amplified products amplified from the TYLCV coat protein. These isolates gave a difference (96%) in the coat protein nucleotide sequence of the virus isolate 10. Furthermore, analysis of some mineral elements in plants infected with TYLCV showed a decrease in the concentrations of magnesium and calcium and an increase in the concentrations of elements sodium and potassium with a significant difference from their normal concentrations in the non-infected plants.

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This study aimed to test the effect of two factors, biological (Bacillus cereus) and physical (UV-C) in degrading of herbicide Lintur residue on wheat plants. Pathogenicity in vitro experiments showed that Pseudomonas fluorescens is not pathogenic on wheat seeds. On the other hand, Lintur had negative effect on bacteria in solid and liquid media. As for the field experiments with regard to Lintur residual in the soil, the results showed that the highest concentration of the herbicide was 7.00 ppm in the treatment of uncultivated soil sprayed with Lintur, while the lowest concentration (below the detectable level) was in the wheat planted soil sprayed with UV-C treated Lintur in the presence of Pseudomonas fluorescens. As for the seed treatment, the highest active compound concentration was 1.90 ppm appeared in the Lintur treated seeds in the absence of other treatments, compared to the lowest residual concentration (0.00) ppm was in seeds treatment with UV-C treated Lintur.