اثر کشندگی عصاره‌ی متانولی چهار گونه ماکروجلبک دریایی قهوه‌ای (Padina australis و Cystoseira trinodis) و قرمز (Hypnea flagelliformis و Gracilaria corticata) روی کنه تارتن دولکه‌ای در شرایط گلخانه

Macroalgae with a variety of biologically active chemicals and biological functions can be a suitable alternative to chemical pesticides. In general, seaweeds live in harsh conditions that create oxidizing agents and secondary metabolites, and these types of compounds have a special biological responsibility. Macroalgae, like other living organisms, are affected by environmental changes, and their secondary compounds, diversity, and living mass change. These changes can be caused by natural factors such as temperature, duration of residence in the ocean, location of macroalgae harvesting, seasonal changes, water acidity, salinity, etc. The extraction method and solvents are also effective in changing the secondary composition of macroalgae. Four species of Phaeophyta and Rhodophyta were collected from the shores of Bushehr in July and were identified by the experts of a reputable company and immediately sent to Ardabil for study. This research was conducted with the aim of investigating the effect of methanolic extract by Soxhlet method of four species of Phaeophyta and Rhodophyta on the mortality of Tetranychus urticae Koch) grown on red bean plant in the greenhouse of Mohaghegh Ardabili University. Mortality effects with leaf immersion method in extract concentrations (control (distilled water), 10 μl/mil and 50 μl/mil) and with 20 adult female T. urticae in each petri dish it was done with three repetitions. The results showed that all concentrations of the extracts were statistically significantly different from the control. In this way, the concentration of 50 μl/mil of G. corticata with an average of 95% and C. trinodis, H. flagelliformis and P. australis with averages of 84.44%, 28.88% and 26.66% respectively had the mortality effect on T. urticae. Therefore, the methanolic extract of G. corticata and C. trinodis species by Soxhlet method can be selected options in creating a natural insecticide formulation in the biological control of the T. urticae.