Indirect Effect of Basf 490 on Adult Amblyseius Fallacis, 1997

• Published in: Arthropod management tests Vol. 23; no. 1; p. 2
• Main Authors: Bostanian, N. J., Racette, G.
• Format: Journal Article
• Language: English
• Published: 01-01-1998
• ISSN: 2155-9856; 2155-9856
• DOI: 10.1093/amt/23.1.2

BASF 490 is an experimental fungicide applied against apple scab in early spring. Fifty dwarf apple trees (cv Liberty) in a row were treated with BASF 490 50 WP on June 11 and again on June 23, 1997. The first treatment corresponded to petal fall and the second treatment corresponded to first cover. Three rows away, the exercise was repeated with Nova 50WP. The trees were sprayed to drip off with a Cyclone hydraulic sprayer (Hector Delorme, Farnam, Qc, Canada). Twenty-four hours after treatment, 12 leaves from the edges of the row and another six from the middle of the row were picked and brought in a cooler to the lab. The check trees were sprayed with water. The leaves, 18 from each treatment, were placed with their upper surface on wet foam in rectangular trays. The wet foam served as a barrier and at the same time kept the leaves fresh. The petioles were covered with wet J-cloth. Six adult predators, 24 to 48 h old, were transferred to the leaves and twospotted spider mites were supplied as prey. The trays were placed in a growth chamber, set at 24° C and 80% RH. The leaves were examined at 24, 48, 72 and 96 h after treatment for adult mortality. At the rates used for apple scab control, residues of neither fungicide had any direct adverse effect on adult predatory mite, Amblyseuis fallacis.