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As the world's most valuable spice, saffron holds significant economic importance in Iran. Rhizoglyphus robini Claparede (Acari: Astigmata: Acaridae) is one of the most critical and damaging pests affecting corm plants globally, including saffron fields in Iran. The repeated use of acaricides has led to the development of resistance in pest populations. Bacterial communities play a crucial role in the various physiological processes of their insect hosts, including the metabolism involved in detoxification. Bioassays against R. robini were performed with two acaricides, abamectin, and propargite, using a filter paper method. Based on the results, the LC50 values of 2.3 and 25 mg a.i./L were estimated for abamectin and propargite, respectively. The impact of antibiotic pretreatment on acaricide toxicity was assessed using six antibiotics: tetracycline, azithromycin, penicillin, cefalexin, cefixime, and streptomycin. The antibiotics (1.5 mL of 100 mg/L) were added to Petri dishes with a layer of filter paper. Mortality was significantly increased in the tetracycline pretreatment group, whereas the other antibiotics showed negligible effects. A bioassay comparing tetracycline pretreatment with a mixture of the other five antibiotics revealed that the antibiotic mixture also significantly enhanced toxicity. Pretreatment with the antibiotic mixture led to a 5.6-fold increase in abamectin toxicity and a 10.2-fold increase in propargite toxicity. To estimate the density of bacterial community in different treatments, total DNA was extracted, and 16S rRNA gene amplification was performed using a general bacterial primer pair. The semi-quantitative PCR results indicated reduced bacterial density in mites treated with tetracycline or an antibiotic mixture compared with the control. Enzymatic assays showed that the activities of detoxification enzymes, including glutathione S-transferases, carboxyl/cholinesterases, and cytochrome P450 monooxygenases, were significantly reduced in mites pretreated with tetracycline or antibiotic mixture. These findings suggest that bacterial community may influence acaricide metabolism by modulating detoxification enzyme activities in their hosts. This study provides a basis for further research into the mechanisms of symbiont-mediated detoxification in pest management. [ABSTRACT FROM AUTHOR]

Antioxidant defense status was examined during early developmental stages of rainbow trout, Oncorhynchus mykiss, as affected by heat shock (HS) treatment to induce tetraploidy. Samples were collected at 3850 degree-min post-fertilization at 10 °C and at eyed, hatch, swim-up, in addition to fry stages to determine the activity of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and levels of vitamin C, A and E as well as malondialdehyde (MDA). HS treatment caused a significant reduction in survival, but not affected growth compared to the control. CAT and SOD activities peaked at hatch, whereas GPx activity reached a maximum at the swim-up stage, showing similar patterns, however, significantly higher activities in the HS group. Vitamin levels were at their minimum at the hatch in both groups, while significantly lower in the HS groups. Vitamin levels were at their highest at the fry stage, with the exception of low vitamin E in the HS group. The levels of MDA showed a steady increase during development, with consistently higher levels in the HS group. These results suggest that HS treatment and/or tetraploidy status cause high oxidative stress, as evidenced by higher activity of antioxidant enzymes and MDA levels, and lower levels of vitamins. [ABSTRACT FROM AUTHOR]