No abstract

A completely randomized design was used, with 5 plants (in 5-gal pots) per treatment. Samples consisted of 2 leaves randomly selected from infested terminals on each of the 5 plants, for a total sample of 10 leaves per treatment for each sample date. Materials were applied 2 Jul, using a 2.5 gpm Arimitsu sprayer at 250 psi through a Spray Systems 5003 nozzle. To evaluate population densities, the bottom surfaces of sample leaves were sprayed with hair spray to immobilize mites, and the number of post-embryonic mites was counted using a binocular microscope.

Phytotoxicity trials on bedding plants, Los Angeles, Co., CA, evaluated the effects of 1X, 2X and 4X rates of Avid 0.15E (0.01 lb (AI)/acre), Broot 50W, Dimilin 25W, Zolone 3E, and Evisect 50SP (1X = 0.5 lb (AI)/100 gal). One flat, containing 9 pony paks with 6 plants, was evaluated per treatment rate for each species. The materials were applied to runoff with a 2.5 gpm piston pump hand sprayer at 180 psi on 15 Jul (temp = 25-28°C). Phytotoxicity readings were compared to a water check 22 and 29 Jul.

In a commercial saran house in Orange Co., CA, 12 square wooden arenas (9 ft2 in area), lined with 3 mil thick polyethylene sheeting, were filled 1 inch deep with moist soil. The top of each arena was covered with wire screening to prevent the escape of snails. Fourteen bare-root chrysanthemum cuttings, 1-m. old, were planted in a 1-ft2 area on the east side of each arena. On the opposite (west) side of the arena, 20 mature (ca. 1 inch diam) snails, collected from an untreated biological control citrus grove, were placed beneath a 1-ft2 wooden harborage. Providing harborage for the snails at a distance of 2 ft from the chrysanthemums roughly approximates field conditions under which snails normally seek cool shelter during the day and actively forage for food at night. Materials were applied 4 Jun. An untreated check was included, with each treatment being replicated 3 times. Bullets and pellets were distributed evenly throughout foliage at a rate proportional to 4 lb (AI)/acre. Paste was applied as one dime-sized drop at each of the 4 corners of the 1-ft2 chrysanthemum planting at a rate proportional to 4 lb (AI)/acre. Arenas were irrigated daily for one hour by overhead sprinklers. The number of dead, moribund and aestivating snails was recorded at 7, 14, and 21 days after application of the materials.

Ten benches (3 ft × 150 ft) of naturally infested chrysanthemums commercially grown for cut flowers, were utilized in this trial. Each bench was divided in half and alternate halves were treated. The remaining halves were left untreated and served as buffers between treatments. Prior to application, each half bench to be treated was divided into 5 sections & 5 stems were randomly selected per section. The total number of aphids from the growing terminal to the 4th fully expanded leaf was counted per stem. Each stem was marked and numbered. The materials and water were applied with a 200 gal Bean sprayer utilizing a hand wand & 4 Cornell nozzles at 300 psi 10 Jul (Temp = 28°C). Posttreatment counts of the marked stems were taken 2 and 7 days after treatment. Data were collected as percent survival per stem. Arcsin square root transformations were performed on the data prior to analysis by ANOVA. Tukey’s procedure was used to separate treatment means.