Two Spotted Spidermite Control Test on Bean, 1978

Paired plants about 8 in. high, greenhouse grown in 4 - in. pots with perlite medium, were trimmed to 2 leaves/plant. Plants were secured in an upright position with plastic ties to bamboo rods inserted in the rooting medium. Each leaf was infested by attaching a section of leaf with a pin from an infested plant removed from a long established mite colony (N. H. Wright Co., Cranbury, NJ 1948). A small amount of lanolin was applied as a collar to each leaf petiole to restrict mite migration. Pinned leaf sections were removed after 24 hours. Formulated chemicals were prepared with water and applied to run-off with a Hudson Climax pneumatic hand-held sprayer. Each treatment was applied to 8 plants or 16 leaves in 3 separate tests. In each test 8 check plants were sprayed with water from a sprayer with no history of chemical use. Leaves were removed within 4 to 8 days post-treatment and both sides were examined under a stereo-microscope for alive and dead mites.