تقويم مخبري أولي لتحضيرات ممرضة من فطر نام طبيعيا و البكتريا التجارية على حشرة حفار الساق (Zeuzera pyrina L. (Lepidoptera : Cossidae

Abstract EN

A fungus was isolated from naturally infected larvae of different stages of Leopard moth, Zeuzera pyrina L.

and identified as Cephalosporium sp.

Corda.

The effect of this natural isolate on the larvae was evaluated.

A suspension of the fungal spores at a concentration of 32xl0^/ml was inoculated on the mid instar larvae and compared with 1% suspension of Bacillus thuringiensis (commercial formula from Sandoz).

A 100% mortality rates were obtained with both natural isolate and commercial preparation of B.

thuringiensis after one week, as compared to 60% in the control (treated with distilled water only).

Two concentrations of fungal spore suspension (10.66xl06 and 16xl06) and 1% commercial bacterial suspension were used to inoculate the first, middle and last larval stages.

The larval mortality rate one week after treatment was 100, 71 and 100% for the first concentration of the fungal spore suspension and 85.7, 71.4 and 85.7% for the second concentration and for the three larval stages, respectively.

At the same time a mortality rate of 100% was obtained with the bacterial suspension and for all three larval stages.

The control (no treatment, distilled water), however, produced 60, 0,0% mortality for the three larval stages, respectively.