Synergistic effect of gamma radiation and entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae on the humoral immune enzyme response in cotton leaf worm Spodoptera littolaris (Boisd).

A., Gabarty; M., El-Sonbaty S.; A., Ibrahim A.

doi:10.21608/eajbsa.2013.13221

Synergistic effect of gamma radiation and entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae on the humoral immune enzyme response in cotton leaf worm Spodoptera littolaris (Boisd).

Document Type : Original Article

Authors

¹ Department of Natural Products Research, National Center For Radiation Research and Technology, Atomic Energy Authority, Cairo, Egyp

² Department of Microbiology Research, National Center For Radiation Research and Technology, Atomic Energy Authority, Cairo, Egypt;

³ Protection Research Institute, Agriculture Research Center, Egypt

10.21608/eajbsa.2013.13221

Abstract

The present study was carried out to investigate the efficancy of substerilizing doses of gamma irradiation or/ and entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae on the humoral immune enzyme response of Spodoptera littolaris larvae. It was found that gamma irradiation of male pupae (50,100&150 Gy) decreases the humoral immune enzyme activity (phenoloxidase, prophenoloxidase, lysozyme) and protein concentration compared to the control of the 6^th instar larvae S. littolaris. Injecting of Lc₅₀ concentration of both B. bassiana (0.4x10⁵sp/µl) and M. anisopliae (8x10⁸sp/µl) to the last 5^th instar larvae of S. littolaris were significantly increased phenoloxidase, prophenoloxidase, lysozym activities and protein concentration after one day, however, they were significantly declined on the second, third and fourth days and remained at a level lower than that of the controls. Both gamma irradiation and entomopathogenic fungi (B. bassiana and M.anisopliae) significantly decreased the immune enzyme activity and protein concentration (p≤ 0.05) after 2, 3 & 4 days. However, this decrease was remarkable in the larvae of irradiated males’pupae (100Gy) which were injected with entomopathogenic fungi. In conclusion, gamma radiation and tested entomopathogenic fungi synergistically inhibitthe immune system of Spodopteralittolaris larvae.

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