فهرست مطالب ghasem askari saryazdi

 Pistachio fruit moth is one of the most important pests of pistachio orchads. In spite of severe damage of this pest in some orchards, the variety of recommended pesticides against it is very limited. Oxydemeton-methyl and fentione have been registered and recommended against this pest. Low efficiencies of these compounds and also the harmful effects of these pesticides on natural enemies are the problems of using these insecticides. In this study, the efficacy of two avermectine based compounds including abamectin and emamectin benzoate+lufenouran, which are effective on the larvae of some lepidopterous pests were tested against pistachio fruit moth. The experiments were performed in two consecutive years in a Randomized Complete Block Design (RCBD) with different doses of the insecticides. To evaluate the effect of pesticides on the pest, dried and damaged seeds by larvae of pest were counted 7, 12, 18 and 25 days after spraying. The final number of seeds per cluster was also recorded and the efficiency of treatments was calculated. The results showed all treatments were effective against larvae of the moth. In general, higher doses of abamectin (0.4 and 0.6 lit/1000 lit) and higher doses of emamectin benzoate+ lufenouran (200 and 250 gr/1000 lit) were more efficient than other treatments. In general aspects, it seems that abamectin in rate of 0.6 lit/1000 lit is the best treatment for controlling this pest.

The diamondback moth, Plutella xylostella has been developed resistance to many groups of pesticides including of pyrethroids. The present study was conducted to evaluate the toxicity of deltamethrin on the third instar larvae of six populations of the pest using leaf dipping method. The results showed that different populations had different susceptibilities to deltamethrin. At the LC50 level, the resistance ratios of the Urmia, Flaverjan, Karaj, Tehran and Naqadeh populations to deltamethrin were 20.75, 21.84, 2.00, 3.08 and 26.26-fold. Resistant populations were selected for 15 generations and their susceptibility to deltamethrin was evaluated. Resistance levels were noticeably increased in these strains and equaled with 91.87, 82.84 and 70.42-fold in Naqadeh, Urmia and Flaverjan populations, respectively. Although, DEM and TPP had no synergistic effect on deltamethrin, treatment with PBO significantly decreased the toxicity of deltamethrin in the tested resistant strains. DEF also exhibited a moderate synergism with deltamethrin. Enzyme analysis proved that the activity of monooxygenase and esterase enzymes in the resistant strains were much stronger than that of glutathione S-transferase. The results showed that the high resistant strain (Naqadeh) of P. xylostella selected by deltamethrin exhibited high cross resistance to hexaflumuron and indoxacarb. This strain also had moderate positive cross resistance to flubendiamide and thiodicarb.

Causes of head and neck cancers (HNCs) are multifactorial, and few studies have investigated the association between chemical exposure and HNCs. The objective of this study was to investigate associations between HNCs, agricultural occupations, and pesticide exposure. The potential for the accumulation of pesticides in the adipose tissue of patients was also investigated.
A structured questionnaire was used to collect information on demographics, occupation, and exposure to pesticides in a hospital-based case-control study. Pesticide residue in the adipose tissue of the neck in both cases and controls was also monitored via gas chromatography–mass spectroscopy.
Thirty-one HNC cases were included in this study as well as 32 gender-, age-, and smoking-matched controls. An agricultural occupation was associated with HNC (odds ratio [OR], 3.26; 95% confidence interval [CI], 1.13–9.43) after controlling for age, sex, and smoking. Pesticide exposure was associated with total HNC cases (OR, 7.45; 95% CI, 1.78–3.07) and larynx cancer (OR, 9.33; 95% CI, 1.65–52.68). A dose-response pattern was observed for HNC cases (P=0.06) and larynx cancer (P=0.01). In tracing the pesticide residue, five chlorinated pesticides, namely dichlorodiphenyltrichloroethane (DDT), dichlorodipheny-ldichloroethane (DDD), dichlorodiphenyldichloroethylene (DDE), dieldrin, and lindane, were identified in the adipose tissue. Chlorinated pesticide detection was significantly associated with HNC (OR, 3.91; 95% CI 0.9–0.16.9).
HNCs were found to be associated with pesticide exposure after controlling for confounders. A high education level was identified as a modifying factor decreasing the risk of HNCs. Further studies with larger number of subjects are recommended to assess these relationships in greater detail.