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Background: Chemical pesticides increasing use caused increased resistance in insects and increases the residue of pesticides in agricultural products and the environment. Objective: The aims of this study was to achieve a safe method and using natural essential oils of Cupressus against adult insects of the wheat flour (Tribolium castaneum Herbst). Methods: A factorial experiment was conducted in a completely randomized design in four replications in 2018. The Cupressus essential oils (EO) Clevenger by water distillation method and measured by GC-MS. Relative growth rate (RGR), repellency and nutritional indicators, and fumigant toxicity of EO on mature Tribolium castaneum Herbst were investigated in 27 ± 1 °C and 65 ± 5 % relative humidity. Results: Alpha-pinene was the major component of the EO in the studied species. The results of the fumigant toxicity test of essential oils showed that increasing concentration and duration of exposure to essential oil caused an increase in the mortality of T. castaneum. Among the studied species, C. sempervirens (France) with LC50 = 256.93 µL / L air had the highest fumigant toxicity (87.5%) on T. castaneum. Conclusion: Based on the insecticides, repellents and nutritional indices effect of Cupressus essential oils on T. castaneum they can be used as a biological management method for controlling storeroom pests.

Background: A significant amount of crop production is destroyed annually by pests in the storage and significant damage is caused to crops. Recently, the use of essential oils as an alternative to pesticides in pest control has been considered. Due to the presence of α-pinene, Cupressus genus is a significant source of plant insecticides that can act as fumigant, repellency and inhibitory insecticides. Objective: The aim of this study was to investigate the insecticidal properties, repellency and nutritional parameters of essential oils of Cupressus species on Sitophilus oryzae in 2018. Methods: The experiment was conducted in a factorial arrangement based on completely randomized design with 4 replications. The essential oils of the different species and populations of Cupressus were prepared by the Clevenger apparatus using a water distillation method. The major constituents in the essential oils were analyzed by GC-MS and the biological effects of the essential oils against adult S. oryzae were investigated. Results: In the analysis of chemical compounds, α-pinene was identified as the main essential oils of the above species. The result showed that among the species, C. arizonica showed the highest Fumigant toxicity to S. oryzae with LC50 = 172.30 μl/L air. In investigating the effect of repellency on S. oryzae, essential oils of C. sempervirens L. var. horizontalis (France) with 80.61 % showed the highest distance. Conclusion: Due to the toxicity and high repellency effect of Cupressus essential oils on S. oryzae, this genus has high potential for use in storage pest control.

Pimpinella anisum L. belongs to Apiaceae family. The samples of vegetative and reproductive organs at different stages of development were gathered and investigated by cell-histology methods. The investigation of the anatomical structure of vegetative organs showed that the secretory ducts are arranged between the parenchymal tissues of the leaf. Section of flower buds revealed that anthers had 4 pollen sacs, the division of pollen mother cell was of the simultaneous type, microspore tetrads were of tetragonal type and the tapetum layer was secretory. The study of the ultrastructure of pollen grains with SEM showed that they had 3 pores. The ovary was found to be two-chambered and two-carpeled the ovule to be anatropous and to have one membrane. In embryogenic investigation it was found that the embryos were globular, cotyledonary and torpedo-shaped and the transition between globular embryos to cordate embryos was found. The vegetative organs were observed to have the general structure of dicotyledons. The development patterns of ovule and embryo sac follow the Polygonum type. Tetrahedral microspore tetrads were observed. The ultrastructure of pollens was found to be similar to those of Smyrnium, a genus of Apiaceae family. All stages of embryogenesis were covered in this study.

A simple and sensitive method using mini-column packed with multi-walled carbon nanotubes (MWCNTs) combined with graphite furnace atomic absorption spectrometry (GFAAS) for preconcentration and determination of ultra trace amounts of As(III) in an aqueous medium is proposed. The procedure is based on the solid phase extraction of the As(III)-sodium diethyldithiocarbamate (As-NaDDTC) chelate on MWCNTs. Various parameters such as the effect of pH, eluent type and volume, amount of sorbent, and matrix effects on the quantitative recoveries of analyte ions were evaluated. It was found that sorption is quantitative and desorption occurs with 4.0 mL of 3.0 mol L−1 HNO3 in acetone. The limit of detection of the method was 0.008 ng mL−1 for GFAAS with enrichment factor of 125 and the relative standard deviation (RSD) 0.97% (n = 8, C = 10 ng mL−1). This method has been applied to the determination of ultra trace As(III) in water and rice plant and its ash successfully.