فهرست مطالب bita valizadeh

Common pistachio psyllid Agonoscena pistaciae Burkhardt & Lauterer (Hem.: Psyllidae) is one of the main pests of pistachio trees in Iran. Given the risks of excessive use of chemical pesticides, it seems that one of the methods to minimize pesticide pollution is to use plant and mineral compounds.

In this research, the mineral composition of diatomaceous earth and the formulated compounds of chinaberry tree (Melia Azedarach) plant extract (A: chinaberry extract + soap and B: chinaberry extract + potassium silicate) were used to investigate the mortality of nymphs and spawning rate.

Investigating the results indicated that the leaves treated with chinaberry extract + soap with a concentration of 3000 mg/liter following 5 and 10 days and the combination of chinaberry extract + soap (3000 mg/liter) and diatomaceous earth (10000 mg) g/liter) following 5 days were reported to have the highest mortality of nymphs and the lowest spawning rate compared to the control group. Moreover, the results have indicated that the spawning rate of the leaves treated with the combination of chinaberry extract + potassium silicate and the combination of chinaberry extract + soap and diatomaceous earth after 15 days is not significantly different compared to that of the control.

Given the favorable effect of the chinaberry + soap and the combination of chinaberry extract + soap and diatomaceous earth in reducing the number of nymphs and the spawning rate, it seems that spraying pistachio trees with these compounds can properly control the psyllid population.

Common pistachio psylla, Agonoscena pistaciae Burckhardt & Lauterer (Hem.: Psyllidae), is one of the most important pests of pistachio trees in Iran. Considering the risks of overusing synthetic chemical pesticides, it seems that the use of mineral compounds as insecticides is one of the ways to reduce the residual amount of dangerous toxins.

In this study, mineral compounds (sulfur, wollastonite, biotite, zeolite, graphite, perlite and feldspar) were used to investigate the oviposition rate of adult insects as well as egg hatching.

The results showed that the leaves treated with feldspar (0.01 ± 0.00), zeolite (0.07 ± 0.001) and perlite (0.97 ± 0.021) at a concentration of 50,000 mg/l were reported to have the greatest decrease in terms of the oviposition rate of the pest in the first year. The results of oviposition rate in the second year indicated that the leaves treated with zeolite and biotite had a significant decrease and increase respectively, compared to the control group. Studies also showed that zeolite treatment could not make any changes in the process of egg hatching.

Given the favorable effect of feldspar, zeolite and perlite in reducing oviposition rate, foliar application of pistachio trees with these compounds can control the population of pistachio psylla.

The elm leaf beetle Xanthogaleruca luteola Müller (Coleoptera: Chrysomelidae), is a serious pest of elm (Ulmus spp.) throughout Iran. In the present study, Lethal and sublethal effects of neem, Achook® containing 0.03% azadirachtin, were assessed on mortality, growth, larval weight and feeding deterrence as well as enzymatic and non-enzymatic activities of third instar larvae of the elm leaf beetle. LC50 and LC30 values of the third instar larvae 48 h post treatment were estimated to be 3.3 and 2.25 ppm respectively. Observations showed higher mortality, increase in larval duration, sterilization of adults, reduction in weight and feeding deterrence after LC30 and LC50 treatments. Biochemical analysis showed changes in the amounts of biochemical components in the treated larvae after 48 h. In the treated larvae, activity level of alanine aminotransferase, alkaline phosphatase, acid phosphatase and α-amylase as enzymatic components and urea and cholesterol as non-enzymatic ones changed significantly in LC50 and LC30 treatments. Aspartate aminotransferase, lactate dehydrogenase, protein, glycogen, and glucose levels decreased in these treatments. The activity level of detoxifying enzymes such as esterase A, esterase B and glutathione S-transferase were significantly affected. Hence, neem is suggested as a safe product may have the potential use as a bioinsecticide in integrated pest management of urban elms where chemical insecticides use are discouraged.