Efficacy of certain entomopathogenic fungi for controlling the potato tuber moth Phthorimaea operculella (Lepidoptera: Gelechiidae) under field conditions in Beheira Governorate, Egypt

Abstract

The Field study was conducted in Barsiq village, Abu Homs city, Beheira Governorate during two successive seasons, summer seasons 2021 and 2022. The main purpose of this study was to evaluate the efficacy of two entomopathogenic `fungi, Beauveria bassiana and Metarhizium anisopliae three concentrations 1x10⁶ , 1x10⁹ and 1x10¹² spores/ml were used. Also, threecommercial bioinsecticides [Biosiana 2.5% WP, Biometa 2.5% WP and Ememactin benzoat 5.7% WG]. The insecticide Methomyl 90% SP, for comparison under field conditions on the population of potato tuber moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) which is considered the main insect pest that attacks potato Solanum tuberosum L. The obtained results showed the efficiency of tested control methods to protect potato foliage from PTM infestation, the highest value was recorded with Methomyl insecticide, followed by E. benzoat, combining E. benzoat with Biosiana, E. benzoat with Biometa, Biosiana, Biometa respectively. While the entomopathogenic fungi B. bassiana 1×10¹², 1×10⁹ , 1×10⁶ and M. anisopliae 1×10¹² , 1×10⁹ , 1×10⁶ , respectively. The relation between treatments and potato yield indicated that the highest increase of the potato yield was recorded with Methomyl insecticide, followed by, E. benzoat, combining E. benzoat with Biosiana, E. benzoat with Biometa, Biosiana and, Biometa respectively, Biosiana, Biometa, B. bassiana and M. anisopliae three concentrations (1×10¹² , 1×10⁹, 1×10⁶ ) spores/ml.