SAIED M. EZZAT, ALI A. EL-SHEIKH AND RANA HUSSIEN MOHAMED HUSSIEN
Department of Pest Physiology, Plant Protection Research Institute, ARC, Giza, Egypt
*(e-mail : ranahussien46@gmail.com; Mobile : 201010352139)
(Received : June 16, 2019; Accepted : August 20, 2019)
ABSTRACT
The global orientation, now-a-days, is directed towards phasing out of chemical pesticides, using entomopathogenic fungi as a safe alternative as biocontrol agent. The Egyptian strain of entomopathogenic fungi, Metarhizium anisopliae AUMC 3262 was tested as a potential biocontrol agent against second and third larval instars of the Egyptian cotton leafworm, Spodoptera littoralis (Lepidoptera : Noctuidae) (Boisd.). Use of different concentrations (107, 106 and 105) of M. anisopliae AUMC 3262 spore suspensions against 2nd larval instar revealed gradual increase in mortality percentage with increasing spore concentration up to 68% using 107 spore concentration. The 3rd larval instar was more resistant, thus showed a lower mortality percentage of 35.71 with 107 spore concentrations. LT50 was 10.8±0.74 and 13.74±0.88 with 2nd and 3rd larvae instars, respectively. This Egyptian strain had another important advantage; it could be mass produced using diphasic fermentation method. The fungus was firstly propagated on different liquid media : malt extract broth (ME), potato dextrose broth (PD) and yeast sucrose (YS) were the best media producing highly mycelial weight with a value of 8.50±0.23, 7.60±0.30 and 7.07±0.35 g/l, respectively. ME gave the highest mycelial dry weight to inoculate different solid substrates for solid state fermentation. An initial assessment indicated that the fungus had the ability to produc easily on crushed rice followed by crushed maize, wheat bran, crushed barley, but no growth on rice husk.
Key words :Metarhizium anisopliae, mass production, Spodoptera littoralis, biological control