بررسی اثرات جانبی قارچ های Beauvaria bassiana و Metarhizium anisopliae روی حشره کامل کفشدوزک هفت نقطه‌ای

The seven-spot ladybird, Coccinella septempunctata L., is one of the most abundant and famous species of predatory insects, which has been widely used in biological control in different parts of the world. Adult larvae and insects feed on aphids, mealy bugs, psyllids, mites, eggs, and young larvae of other insects. In this research, experiments were conducted to determine the effect of two species of insect pathogenic fungi Beauveria bassiana (IRAN4887C) and Metarhizium anisopliae (which were previously isolated by trapping and morphologically and molecularly identified) on the seven-spot ladybird were studied in laboratory (27±1°C and 65±5% RH) and field conditions. In laboratory conditions, three different concentrations of two types of pathogenic fungi in three replicates (10 complete insects in each replicate), and in field conditions, three treatments with a concentration of 3.3×107 conidia/ml of the mentioned fungi along with the control treatment (distilled water), foliar spray was done in four replicates. The experiments were conducted in a completely random design, and the results of variance analysis of different concentrations of each fungus on the seven-spot ladybirds showed that their insecticidal effect significantly differed. The laboratory results showed that the M. anisopliae with a concentration of 108 conidia/ml had the most lethal impact (80.6%) on the seven-spot ladybirds. However, the concentrations of 106 (60.3%) and 107 conidia/ml (70%) had a significant lethal effect and did not have a statistically significant difference. Also, B. bassiana in 108 (90.6%) concentrations, and 107 conidia/ml (90%) had no statistically significant difference in the adult stage of seven-spot ladybirds mortality. The results of analyzing the variance of M. anisopliae and B. bassiana fungi on the adult ladybird in field conditions showed that Beauveria has the highest lethality (71.25%) followed by Metarhizium with 51% lethality on the seven-spot ladybird in field conditions. It should also be mentioned that the control in the field had a natural mortality rate of 19%.