Screening of Potential Insect Pathogenic Fungi for Controlling Cabbage Aphid (Lipaphis erysimi)

Abstract

The objective of this research was to search for potential insect pathogenic fungi to control
cabbage aphid (Lipaphis erysimi). The survey and sample collection were performed in farmer crop fields
and natural forest areas in eight provinces of Thailand and nine provinces of Lao PDR. A total of 100 isolates
of fungi were found (53 isolates from Thailand and 47 isolates from Lao PDR). All isolates were identified
to be 12 isolates of Metarhizium (53 isolates from Thailand and 47 isolates from Lao PDR), 53 isolates of
Beauveria (25 isolates from Thailand and 28 isolates from Lao PDR) and 35 isolates of Paecilomyces
(23 isolates from Thailand and 12 isolates from Lao PDR). Control potential of pathogenic fungi were
tested on the cabbage aphid under laboratory condition. The result revealed that Metarhizium isolate
PSON1 from Lao PDR showed the highest potential control to cabbage aphid with the mortality of
32.5, 58.75 and 90.00% at 48, 72 and 96 hours after direct spraying on the aphids, respectively.