Effects of the timing of applications on the incompatibility of three fungicides and one isolate of the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (Deuteromycotina)

• Published in: Journal of applied entomology (1986) Vol. 127; no. 7; pp. 421 - 426
• Main Authors: Kouassi, M, Coderre, D, Todorova, S.I
• Format: Journal Article
• Language: English
• Published: Berlin, Germany Blackwell Verlag GmbH 01.08.2003; Blackwell
• Subjects: application timing; Beauveria bassiana; biocontrol compatibility; Biological and medical sciences; Biological control; biological control agents; Control; copper oxide; entomopathogenic fungi; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; fungicides; insect pests; IPM; Lygus lineolaris; mancozeb; metalaxyl; mortality; mycoinsecticides; Phytopathology. Animal pests. Plant and forest protection; Protozoa. Invertebrates; synergism; Fungi; Beauveria bassiana; Entomopathogen; Pesticides; Application method; Fungi Imperfecti; Fungicide; Thallophyta
• ISSN: 0931-2048; 1439-0418
• DOI: 10.1046/j.1439-0418.2003.00769.x

: The effect of timing of application on the incompatibility of three fungicides (metalaxyl, mancozeb, copper oxide) and isolate MK2001 of the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin was assessed in vitro. Isolate MK 2001 at 1 × 107 conidia/ml concentration was highly pathogenous to adults of Lygus lineolaris (Hemiptera) (84% mortality at day 4 post‐treatment). The fungicides at the manufacturer recommended rate (1X) were strongly fungistatic and inhibited the fungal isolate radial growth on Sabouraud dextrose agar (SDA). Mancozeb, metalaxyl and copper oxide exhibited insecticidal activity of 24, 40 and 48% respectively, on L. lineolaris adults. It is clear that application of the fungal isolate MK2001 2–4 days before applying fungicides metalaxyl, mancozeb or copper oxide synergized the insecticidal effect of the isolate. On the contrary, application of metalaxyl, mancozeb, copper oxide 2–4 days before applying isolate MK2001 antagonized the insecticidal effect. The simultaneous use of each fungicide (metalaxyl, mancozeb or copper oxide) and the isolate gave lesser insect mortality. This study revealed that although some fungicides are incompatible for use alongside fungal isolates, the proper evaluation of their time of use could be beneficial in biological control or IPM programmes. Furthermore, the application of B. bassiana isolate MK2001 followed by fungicide application could synergize insecticidal activity.