Tractor-mounted Boom Sprayer Research Articles

Control of Sweetpotato Whitefly and Geminivirus Transmission on Staked Tomato, Spring, 1990

Abstract Tomatoes spaced 18 in apart were transplanted on 29 Jan in 9-row plots 24 ft long on 9 raised soil beds (6 ft centers). Beds were fumigated at formation with 13.5 gal/acre Vorlex and covered with whiteface polyethylene mulch. Directly adjacent were 3 beds of 100% geminivirus-infected tomatoes planted the previous November and partially protected from a December freeze. A completely randomized split block design was used with 4 replications and 3 main plot treatments; JMS Stylet Oil, insecticide, and an unsprayed check. Insecticide plots were split into 3 subplots, each 3 rows wide. Concentrations of all treatments were fixed throughout the experiment but rates per acre increased as nozzles were added to accommodate larger plants. Manzate 200 (1.5 lb/acre) and Tri-Basic Copper (3 lb/acre) were applied weekly, Bravo (2 lb/acre) and Javelin SC at 1.2 qt/acre were applied twice to control Spodaptera spp. Treatment applications began 12 Feb and continued twice weekly until harvest using a tractor-mounted boom sprayer with 4 drop lines holding a maximum of 24 nozzles fitted with Albuz ceramic hollow cone tips (ATR brown delivering ca. 0.26 gal/min @ 400 psi). Whitefly immatures were counted at weekly intervals on the terminal leaflet of the 5th, 6th, or 7th leaf from the top (depending on plant maturity) from 6 randomly selected plants per subplot. Adults were sampled by carefully inverting the 3rd leaf from the top of 3 randomly chosen plants per subplot. Plants affected by geminivirus were marked as symptoms appeared. All fruit of marketable size were picked and graded on 19 Apr. Culls were removed and the remaining fruit separated into medium, large, and extra-large categories with a mechanical grader. Dollar value was calculated on the basis of $5.00/25 lb box for medium and large fruit and $7.00/box for extra-large fruit. A repeated measure analysis of variance for each whitefly lifestage was used over all sample dates and a separate analysis of variance was calculated for adults on each of the last 4 sample dates. A log10(x + 1) transformation was used to normalize counts of immatures because of the large number of zeros and high numbers in the data set.

Colorado Potato Beetle Control with Natural Product Insecticides, 1990

Abstract Certified B-size seed potatoes were planted 15 May at the University of Minnesota Agricultural Experiment Station, Crookston. Plots were 4 rows wide, 15.3 m (50 ft) long, with 91 cm (3 ft) spacing between rows and 30 cm (1 ft) spacing between plants. A completely randomized plot design with 3 replications was used. Plots were scouted daily for CPB egg masses beginning 20 Jun. When egg masses were found, they were flagged and checked daily for hatch. Timing of first spray application was at 30% hatch and subequent applications on a 7 d schedule. Plots were sprayed 3 times for each generation of CPB larvae: 28 Jun, 5 and 12 Jul for first generation and 25 Jul, 2, and 9 Aug for 2nd generation. Natural product insecticides used in this experiment were Bacillus thuringiensis var. san diego (MYX 1806), and B. thuringiensis var. tenebrionis (Trident) and neem (Margosan-O). Insecticidal sprays were applied using a tractor-mounted boom sprayer, with a single hollow cone nozzle over each row. Sprays were applied in 654 liters of water per ha (70 gal/acre) at 827 kPA (120 psi). Data were collected from the center 2 rows. Larvae were counted on 20 plants per plot. Data were expressed as mean number of larvae or plant injury (percent defoliation) × number of days elapsed, i.e., Area Under the Curve (AUC). AUC for CPB was computed separately for the first and second generation then summed. Two-way analysis of variance was used to test for treatment differences.

Control of Insect Pests of Squash, Fall, 1991

Abstract Squash was planted in hills 2.5 ft apart on raised beds on 4 Sep. Plots consisted of four 25-ft rows spaced 6 ft apart and separated by 15-ft alleys. All plots were treated weekly with chlorothalonil (Bravo) at a rate of 1.5 lb (AI)/acre beginning on 13 Sep. Four treatments and a check were replicated four times in a randomized complete block design. Treatments were applied on 18, 26 Sep, 2, and 9 Oct with a 12-ft, tractor-mounted boom sprayer with 18 Albux (brown) ceramic hollow cone nozzles 8 inches apart, delivering 145 gal/acre at 200 psi. On 14 Oct, five plants from the middle two rows in each plot were examined for whitefly adults, aphids, pickleworm and melonworm larvae, and pickleworm damage to fruit and blossoms. Two lower leaves were collected from each of three plants per plot for estimating numbers of immature whiteflies. Two leaf disks, 0.8 inches in diameter, from half of each leaf, were examined. The center rows in each plot were harvested on 14, 16, 22, and 24 Oct. After this date all fruit showed symptoms of viral infection.

Control of Colorado Potato Beetle and Potato Leafhopper, 1991

Abstract Potatoes were planted 14 May at the Research Farm of the Red River Valley Potato Growers Association, Grand Forks, ND. Plots were 4 rows wide, 14 m (45 ft) long, with 96 cm (38 in) spacing between rows and 30 cm (12 in) between plants. Plots were separated on all sides by 1.9 cm (6.3 ft) of cultivated soil. Eight experiments were planted in the same field. A completely randomized plot design with 4 replications was used. In all eight experiments, CPB control was the primary objective. Experiment 1 was to evaluate neem (Margosan-O) alone or in combination with other insecticides. Experiment 2 was to evaluate several conventional insecticides and Kryocide. Experiment 3 was to compare several commercial Bacillus thuringiensis insecticides at 3 rates each. Experiment 4 was to evaluate neem (RH-9999) alone or in combination with other insecticides. Experiment 5 was to compare 3 Bacillus thuringiensis insecticides from Ecogen Inc. at 2 rates each. Experiment 6 was to evaluate application of Furadan 4 F applied as a systemic spray at drag-off. Experiment 7 was to compare performance of several insecticides when first sprays were applied at different stages of egg hatch or larval development. Experiment 8 was to compare different insecticide rotation schedules. Plots were scouted daily for CPB egg masses beginning 8 Jun. When egg masses were found these were flagged and checked daily for hatch. Timing of first spray application (except in Experiment 6) was based on egg hatch. Five treatment schedules were used: 0 = untreated control (UTC), 1 = Furadan 4 F applied as a spray 6 Jun just prior to drag-off, 2 = first application at 30% hatch of flagged CPB egg masses (i.e., first eggs to hatch for that generation), 3 = first application at first appearance of 2nd instar, 4 = first application at first appearance of 3rd instar. Spray applications for schedule 2 were made on 19, 26 Jun, and 5 Aug (second generation), spray applications for schedule 3 on 21, 28 Jun, and 8 Aug (second generation), and spray applications for schedule 4 on 24 Jun, 1 Jul, and 9 Aug (second generation). Insecticidal sprays were applied using a tractor-mounted boom sprayer, with a single Teejet nozzle over each row. Sprays were applied in 150 liters of water/ha (40 gal/acre) at 275 kPa (40 psi). CPB larvae (small = 1st and 2nd instar, large = 3rd and 4th instar) were counted on 10 randomly selected whole plants. PLH nymphs were counted on 35 mid-plant leaves. Leaf loss due to defoliation by CPB feeding and hopperburn injury caused by PLH was estimated visually as percent foliage lost. CPB were counted on 28 Jun and 10 Jul. Defoliation was estimated on 28 Jun, 10, 25 Jul, 9, and 16 Aug. PLH were counted on 9 and 15 Aug. Hopperburn was estimated on 16 Aug. Data were expressed as mean insect numbers or plant injury.

Control of Leafminers on Cantaloupe, 1991

Abstract Cantaloupes were direct seeded into “Yuma Beds” on 18 Mar. Plants were thinned at 12 inch intervals on 5 Apr. Plots consisted of six 60-ft long beds spaced 80 inches apart and bordered on each side by an untreated bed, arranged in a completely randomized block design with 5 replicates. Applications were made on 23 Apr, 6, 20, 25 May, and 3 Jun. Foliar insecticide treatments were applied with a tractor-mounted boom sprayer (4 nozzles/bed spaced 12 inches apart) operated at 60 psi, delivering 25 gal/acre. Spreader-sticker (Raincoat) was included in all spray treatments at a rate of 6 oz/acre. Plots were sampled on 15, 22, 30 May, and 6 Jun. Samples consisted of 20 leaves collected from the center two rows of each replicate. Leaves Were taken to the laboratory, and the numbers of live and parasitized leafminer larvae present were recorded for each plot. Data were analyzed for treatment differences using ANOVA and Ryan’s Q-test (Proc GLM).

Control of Colorado Potato Beetle, Potato Leafhopper, and Green Peach Aphid, 1991

Abstract Potatoes were planted 15 Mayat the University of Minnesota, Agricultural Experiment Station, Rosemount. Plots were 4 rows wide, 10.6 m (35 ft) long, with 102 cm (40 in) spacing between rows and 30 cm (12 in) between plants. Plots were separated on all sides by 2.0 m (6.7 ft) of cultivated soil. Eight experiments were planted in the same field. For each experiment, a completely randomized plot design with 4 replications was used. In all eight experiments, CPB control was the primary objective. Experiment 1 was to evaluate neem (Margosan-O) alone or in combination with other insecticides. Experiment 2 was to evaluate several conventional insecticides and Kryocide. Experiment 3 was to compare several commercial Bacillus thuringiensis insecticides at 3 rates each. Experiment 4 was to evaluate neem (RH-999) alone or in combination with other insecticides. Experiment 5 was to compare 3 Bacillus thuringiensis insecticides from Ecogen Inc. at 2 rates each. Experiment 6 was to evaluate application of Furadan 4 F applied as a systemic spray at drag-off Experiment 7 was to compare performance of several insecticides when first sprays were applied at different stages of egg hatch or larval development. Experiment 8 was to compare different insecticide rotation schedules. Plots were scouted daily for CPB egg masses beginning 8 Jun. When egg masses were found they were flagged and checked daily for hatch. Timing of first spray application (except in Experiment 6) was based on egg hatch. Five treatment schedules were used: 0 = untreated control (UTC), 1 = Furadan 4 F applied as a spray 6 Jun just prior to drag-off, 2 = first application at 30% hatch of flagged CPB egg masses (i.e., first eggs to hatch for that generation), 3 = first application at first appearance of 2nd instar, 4 = first application at first appearance of 3rd instar. Spray applications for schedule 2 were applied 17-18, 24 Jun, 23 (second generation), 29 Jul, 6, and 13 Aug. Spray applications for schedule 3 were applied 19, 27 Jun, 24 Jul (second generation), 31 Jul, 7, and 14 Aug. Spray applications for schedule 4 were applied 22 Jun, 26 Jul (second generation), 8, 12, and 16 Aug. Insecticidal sprays were applied using a tractor-mounted boom sprayer, with drop nozzles. Sprays were applied in 739 liters of water/ha (79 gal/acre) at 620 kPa (90 psi). CPB larvae (small = 1st and 2nd instar, large = 3rd and 4th instar) were counted on 8 randomly selected whole plants, PLH nymphs and GPA apterae were counted on 35 mid-plant leaves. Leaf loss to defoliation by CPB feeding was estimated visually as percent foliage lost. CPB were counted on 21, 26 Jun, 25 Jul, 1, 9, and 15 Aug; defoliation was estimated on 28 Jun, 3, 10, 17, 22, 30 Jul, 5, and 19 Aug; PLH were counted 30 Jul and 29 Aug; GPA were counted 29 Aug. Data were expressed as mean insect numbers or plant injury.

Effect of Insecticides on Lepidopterous Larvae and Leafminers on Tomatoes, 1991

Abstract Seedlings were transplanted in a sandy loam type soil on 17 Jun at the University of California's South Coast Field Station in Santa Ana, CA. Experimental plots were 4 rows wide (5-ft centers) by 40 ft long and separated by a 5-ft buffer. The tomato transplants were sprinkle irrigated for 1 week, and drip irrigated thereafter (water pH 7.2- 7.5). Treatments were replicated 4 times in a randomized complete block design. Weekly applications were initiated at first fruiting. Application dates were 1, 7, 15, 22, 29 Aug, 5, and 7 Sep. A tractor-mounted boom sprayer with 6 nozzles per row incorporated D-3 orifice disks, #25 cores, and 50 mesh screens. Operating pressure was 100 psi delivering 100 gal/acre. Spreader sticker (Leaf Act 80) was included for all treatments at 0.04%. Leafminer populations were evaluated by weekly counts of leafminer prepupae and pupae in four 9 by 11 inch trays/replicate from 30 Jul through 16 Sep, inclusive. On 16-18 Sep, 200 mature-green to ripe fruit were harvested from the center 2 rows of each replicate (800 per treatment) and examined for internal damage (primarily H. zea) and external damage (primarily S. exigua and K. lycopersicella).

Chemical Trials and Effects on Arthropods in Celery, 1990

Abstract Celery was transplanted in a sandy loam soil on 15 Aug at the University of California’s South Coast Field Station. The plants were sprinkler irrigated for three weeks and drip irrigated (water pH 7.2-7.5) thereafter. Experimental plots wee four beds wide (two rows per bed on 40-inch centers) by 40 ft and separated by a 5 ft buffer with four replicates of each treatment in randomized complete block design. Weekly application dates included 26 Sep, 2, 12, 16, 23, 30 Oct, and 6, 13 Nov. All chemicals were applied by a tractor-mounted boom sprayer operated at 100 psi. Nozzles were 4 per bed and carrier (H20) was at 100 gal/acre. Disc-type cone nozzles incorporated D3 oriftce discs, #23 or #25 cores and 50-mesh screens. All treatments received spreader-sticker. Antifoam (No-Foam°) was used with all treatments. Leafminer populations were evaluated by weekly counts of leafminer prepupae and pupae in four 5.5 × 11 inch trays/replicate when the plants reached a suitable height. The number of dead adult parasites of Liriomyza species was recorded in the same manner as for pupal counts. Evaluation of Lepidoptera populations was based on number of damaged plants found in 25 plants per replicate (100/treatment) from the center two rows of each replicate at harvest (20 Nov). Beet armyworm and black cutworm damage were recorded separately.

Impact of Insecticides on Lepidopterous Larvae and Leafminers on Tomatoes, 1990

Abstract Seedlings were transplanted in a sandy loam type soil on 9 Jul at the University of California's South Coast Field Station in Santa Ana, California. Experimental plots were 4 rows wide (5-ft centers) by 40 ft long and separated by a 5-ft buffer. The tomato transplants were sprinkle irrigated for 1 wk, and drip irrigated thereafter (water pH 7.2- 7.5). Treatments were replicated 4 times in a randomized complete block design. Weekly applications were initiated at first fruiting. Application dates included 17, 24, 30 Aug and 6, 13, 21, 27 Sep, and 4 Oct. A tractor-mounted boom sprayer with 4-6 nozzles/row (as plant height and density increased) incorporated D-3 orifice disks, #23-25 cores, and 50 mesh screens. Operating pressure was 100 psi delivering 100 gal/acre. Spreader sticker (Leaf Act 80) was included for all treatments at 0.04%. Leafminer populations were evaluated by weekly counts of leafminer prepupae and pupae in four 9 by 11 inch trays/replicate from 22 Aug through 3 Oct, inclusive. On 10 Oct, 200 mature-green to ripe fruit were harvested from the center 2 rows of each replicate (800 per treatment) and examined for internal damage (primarily H. zea) and external damage (primarily s. exigua and K. lycopersicella). Leafminer populations were moderate throughout this test. Some insecticides increased leafminer density was compared to the control plots. Beet armyworm populations were moderate, tomato pinworm populations were low and tomato fruitworm populations were low. No phytotoxicity was observed in any treatment.

Control of Colorado Potato Beetle with Natural Product Insecticides, Grand Forks, 1990

Abstract Natural product insecticides used in this experiment were Bacillus thuringiensis var. san diego (MYX 1806), B. thuringiensis var. tenebrionis (Trident and BK-102) and azadirachtin (Margosan-O) from the neem tree, Azadirachta indica. Plots were planted 15 May at the Research Farm, Red River Valley Potato Growers Association, Grand Forks, N.D. Plots were 6 rows wide, 16.8 (55 ft) long, with 91 cm (36 inches) spacing between rows and 30 cm (12 inches) between plants. The two center rows of each plot were planted with certified 'Red Pontiac' seed pieces, the remaining four rows were planted with certified, B-size, 'Russet Burbank.' Plots were separated on all sides by 1.8 m (6 ft) of cultivated soil. A completely randomized plot design with 4 replications was used. Plots were scouted daily from CPB egg masses beginning 21 Jun. When egg masses were found these were flagged and checked daily for hatch. Timing of first spray application was based on egg hatch. Three basic spray schedules were used: first application at 30% hatch of flagged egg masses and subsequent application on either a 7 d or 10 d schedule, or first application at 30% hatch of all eggs (unflagged) laid on or before that sampling date and subsequent applications on a 7 d schedule. Plots were sprayed 1-3 times for each generation of CPB larvae: 29 Jun (30% hatch of flagged eggs—1st generation) 2 Jul (30% total hatch—1st generation), 5,9, 12, 16, 19 and 31 Jul (30% hatch of flagged eggs—2nd generation), 6 Aug (30% total hatch—2nd generation), 10, 13 and 14 Aug. Insecticidal sprays were applied using a tractor-mounted boom sprayer, with a single Teejet nozzle over each row. Sprays were applied in 150 liters water/ha (40 gal/ acre) at 275 kPa (40 psi). All data were collected from the two center rows of each plot. CPB larvae (small = 1st and 2nd instar, large = 3rd and 4th instar) were counted on 20 randomly selected whole plants per plot, PLH nymphs were counted on 35 mid-plant leaves per plot. Leaf loss to defoliation (by CPB) and hopperbum (injury caused by PLH) were estimated visually (by 2 individuals per sampling date) as percent foliage lost. CPB were counted on 4, 10 and 17 Jul, and 1, 8 and 17 Aug; defoliation was estimated on 10, 17 and 24 Jul, 1, 8 and 15 Aug; PLH were counted on 4, 10, 17 and 24 Jul, 1, 8 and 17 Aug; hopperbum was estimated on 1, 8 and 15 Aug. Insect data and plant injury ratings were expressed as mean insect numbers or plant injury × number of days elapsed (= Area under Curve). AUC for CPB was calculated separately for 1st and 2nd generations, and then summed. Yields were obtained 2 Oct by harvesting one center row from each plot. Two way analysis of variance was used to test for treatment differences in pest densities, plant injury and yield. The 1990 growing season at Grand Forks was characterized by severe drought from late Jun through harvest.

Colorado Potato Beetle Control, 1990

Abstract Insecticide trials were conducted at the MSU Montcalm Potato Research Station, Entrican, Mich. 'Atlantic' seed potatoes were planted on 1 May, 8 inches within the row and 34 inches between rows. Treatment plots consisted of three 45 ft-long rows and were arranged in a randomized complete block design with 4 replications/treatment. Plots were separated by either 6 ft of bare ground or 2 rows of potatoes that were treated with Temik 15 G (3 lb [AI]/acre) in furrow at planting. Granular systemic treatments were applied at planting in furrow (Temik sprinkled directly over seed potato) or on 24 May, where Temik was incorporated at hilling. Foliar treatments were applied using a tractor-mounted boom sprayer (30 gal/acre, 40 psi) utilizing 3 nozzles/row. The middle nozzle directed spray down over the top of the plant and the other nozzles directed spray at the sides. Foliar treatments were applied on 24 and 28 Jun, and on 3 Jul. Insecticide effectiveness was determined by counting the total number of insects found on 2 randomly selected plants in each replication on 27 Jun and on 2 and 6 Jul. Pre-spray counts were made on 14 and 21 Jun, two plants per plot in the Temik-treatments, and 40 randomly selected plants from the remaining area were sampled. Plants were visually assessed for defoliation and given a damage rating (1 = no defoliation, 5 = total defoliation) on 11 Jul. On 27 Sep the middle 45 ft row of each treatment was harvested. Tubers were separated by size (As and B's) and weighed.

Control of Sweetpotato Whitefly and Associated Disorders on Staked Tomato, 1989

Abstract Tomatoes spaced at 18 inches were transplanted on 7 Aug in 3-row plots 24 ft long on 3 raised soil beds (6-ft centers) which were fumigated with 13.5 gal/acre Vorlex and covered with plastic mulch. The experimental design was completely randomized with 5 insecticide treatments and a control replicated 4 times. Manzate 200 (1.5 lb/acre) and Tri-Basic Copper (3 lb/acre) were applied weekly, and Javelin SC at 1.2 qt/acre was applied twice to control Spodoptera spp. Insecticide applications began 13 Oct and continued weekly for 6 wk using a tractor mounted boom sprayer delivering 150-200 lb/inch2 to 4 drop lines with a maximum of 24 T-jet hollow cone nozzles fitted with brass TLX-3 80° tips and 100 mesh stainless steel strainers with check valves. An adjuvant (Induce at 1 pt/100 gal) was applied as an adjuvant with all treatments including the control. Whitefly immatures were counted on the terminal leaflet of the 6th, 7th and 8th leaf from the top on 9 randomly selected plants/plot. Plants affected by geminivirus were marked as symptoms appeared. All fruit of commercial size were harvested on 21 Nov and 4 Dec, graded for quality and size and weighed. Fruit were held for 4 d in ethylene (5 ppm), and sorted according to degree of ripeness. Fruit that were still between 10% and 50% green were considered "irregular" in ripeness. Yield values was assessed according to 8 Dec 1989 prices irrespective of irregular ripening.

Evaluation of Insecticides for Insect Control in Alabama Soybeans, 1990

Abstract This field test was conducted in conventionally planted and tilled soybeans at the Plant Breeding Unit of Auburn University, Tallassee, Ala. Four replicates of 15 treatments and an untreated control were planted in a randomized complete block design. Each 0.014-acre plot was 4 rows wide (36-inch row spacing) and 50-ft long. Plots were separated by 2 border rows of soybeans and replicates were separated by a 25-ft mowed alley. Treatments were applied on 21 Sep using a tractor-mounted boom sprayer equipped with 2, TX-3 hollow cone nozzles/row operating at 40 psi and delivering 6 gal/acre. A sweep net was used to sample velvetbean caterpillar larvae. Larvae were classified as small (instar 1-2), medium (instar 3-4), or large (5 + ); they were then counted and recorded. Then sweeps per plot were taken prior to treatment and 20 sweeps/plot were taken at 3 and 6 DAT.

Chemical Trials and Effects on Arthropods in Celery, 1989

Abstract Celery was transplanted in a sandy loam soil on 11 Aug at the University of California's South Coast Field Station. The plants were sprinkler irrigated for 3 wk and drip irrigated (water pH 7.2-7.5) thereafter. Experimental plots were 3 beds wide (2 rows/bed on 40-inch centers) by 50 ft and separated by a 5 ft buffer with 4 replicates of each treatment in randomized complete block design. Weekly application dates included 22, 28 Sep, 5, 12, 19, 26 Oct and 3, 10, 16 Nov. All chemicals were applied by a tractor-mounted boom sprayer operated at 100 psi. As plant height and foliage density increased, nozzles varied from 2—4 per row and carrier (H20) increased from 50 gal/ac (22 Sep) to 100 gal/ac (28 Sep on). Disc-type cone nozzles incorporated D3 orifice discs, #23 or #25 cores and 50-mesh screens. All treatments received spreadersticker. Antifoam (No-Foam) was used with all treatments. Leafminer populations were evaluated by weekly counts of leafminer prepupae and pupae in four 5'/2 × 11 inch trays/replicate when the plants reached a suitable height. Acutal sampling dates were 27 Sep, 4, 11, 18, 25 Oct and 1, 9, 15 Nov. The number of dead adult parasites of Liriomyza species were recorded in the same manner and on the same dates listed for pupal counts. Evaluation of Lepidoptera populations was based on number of damaged plants found in 25 plants/replicate (100/treatment) from the center two rows of each replicate at harvest (20 Nov). Beet armyworm and black cutworm damage were recorded separately.

Impact of Insecticides on Lepidopterous Larvae and Leafminers on Tomatoes, 1989

Abstract Seedlings were transplanted in a sandy loam type soil on 6 Jul at the University of California's South Coast Field Station in Santa Ana, California. Experimental plots were 4 rows wide (5-ft centers) by 40 ft long and separated by a 5-ft buffer. The tomato transplants were sprinkle irrigated for 1 wk, and drip irrigated thereafter (water pH 7.2— 7.5). Treatments were replicated 4 times in a randomized complete block design. Weekly applications were initiated at first fruiting. Application dates included 15, 22, 29 Aug and 6, 12, 19, 26 Sep. A tractor-mounted boom sprayer with 4—6 nozzles/row (as plant height and density increased) incorporated D-3 orifice disks, #23-25 cores, and 50 mesh screens. Operating pressure was 100 psi delivering 100 gal/acre. Spreader sticker (Leaf Act 80) was included for some treatments at 0.04%. Leafminer populations were evaluated by weekly counts of leafminer prepupae and pupae in four 9 by 11 inch trays/replicate from 21 Aug through 25 Sep, inclusive. On 2 Oct, 200 mature-green to ripe fruit were harvested from the center 2 rows of each replicate (800/treatment) and examined for internal damage (primarily H. zea) and external damage (primarily S. exigua and K. lycopersicon). Leafminer populations were low throughout this test. Some insecticides increased leafminer density as compared to the control plots. Beet armyworm populations were moderate, tomato pinworm populations were low and tomato fruitworm populations were low. No phytotoxicity was observed in any treatment.

Colorado Potato Beetle Control, Foliar Insecticides, 1988

Abstract Trials of foliar sprays to Colorado potato beetle were conducted at the Michigan State University Montcalm Potato Research Farm, Entrican, MI. Potatoes were planted on 13 May 1988. Plots were 3 rows wide (34 inch row spacing) by 40 ft long and treatments were arranged in a randomized complete block design with 4 replications/treatment. Adjacent plots were separated by two untreated rows. Treatments were applied on 17 and 23 Jun, and 1 Jul with a tractor-mounted boom sprayer at 30 gal/acre, 40 psi, with a cluster of 3 nozzles over each row. The middle nozzle directed spray down over the top of the plant, and the other nozzles directed the spray at the sides of the plant. Insects were counted from randomly-selected plants (1/plot prior to treatment, 2/plot for post-spray samples) on 14 Jun (pretreatment count), 21 and 23 Jun, and 7 Jul. Damage ratings both on a per plot and a per plant (2 plants/plot) basis were made on 7 Jul. The center row of each plot was harvested and potatoes sorted by size and weighed on 5 Oct.

Management of Lepidopterous Pests on Collards, 1989

Abstract ‘Georgia’ collard seeds were incorporated into a germination mix (Pro-Mix) and direct seeded into a Rockdale soil at the University of Florida’s Tropical Research and Education Center on 2 February 1989. Plants were spaced 1 ft apart, one row/bed, on 72 inch-center beds. Treatments were replicated 4 times in a randomized complete block design. Treatment plots were 4 rows (2 beds) by 40 ft long. A 10-ft long section of nontreated plants separated replicates; treatments within a replicate were separated by one nontreated bed and a 6 ft alleyway. Applications were made on 3, 10, 17, 23, and 31 Mar and 11 Apr, using a tractor-mounted single-bed boom sprayer that operated at 250 psi and delivered 100 gal/acre through 5 D-4, #24 disc type cone nozzles at 3 mph. The numbers of small, medium, and large larvae and pupae of diamondback moth (DBM), parasitized DBM pupae, small, medium, and large larvae of beet armyworm (BAW), and small and large larvae of cabbage budworm (CBW) were recorded on 8 plants/replicate on 6 dates. Foliage injury was rated on 24 plants/replicate at harvest (24 Apr), using a scale from 1-5 (1 = 0-3%, 2 = 4-10%, 3 = 11-25%, 4 = 26-50%, and 5 = 51-100% of leaves damaged/plant; based on number of leaves/plant). A second rating was taken by assigning plants to one of these 5 damage indices based on visual estimates.

Management of Lepidopterous Pests on Cabbage, 1989

Abstract ‘Rio Verde’ cabbage seeds were direct seeded at the University of Florida’s Tropical Research and Education Center on 22 Dec ‘88. Plants were spaced 1 ft within rows and 30 inches apart between rows on 72 inch-center beds. Treatments were replicated 4 times in a randomized complete block design. Treatment plots were 4 rows (2 beds) by 40 ft long. A 10-ft long section of nontreated plants separated replicates; treatments within a replicate were separated by one nontreated bed and a 6 ft alleyway. Efficacy and residual activity of CME 13406 (0.03 lbs [AI]/acre) were evaluated using 3 treatment strategies; applications made weekly for 3 wk and then at 2 wk intervals thereafter; applications made at 2 wk intervals until heading and then judiciously thereafter; and applications made once before and at heading and at 3 wk intervals thereafter. These were compared to applications of CME 13406 + Dipel 2 × (0.5 lbs/acre) made at 2 wk intervals before heading and weekly thereafter, Lannate (0.9 lbs [AI]/acre) + Dipel 2 × (0.5 lbs/acre) applied weekly, and nontreated plants. Weekly applications of Lannate + Dipel were made on 9 dates (2, 9, 17, and 24 Feb, and 2, 9, 16, 23, and 30 Mar). Treatments of CME 13406 applied weekly for 3 wk and then at 2 wk intervals thereafter were made on six dates (2, 9, and 17 Feb, and 2, 16, and 30 Mar). Treatments of CME 13406 applied at 2 wk intervals until heading and then applied judiciously thereafter with and without Dipel 2 × were made on 6 dates (2, 17, and 24 Feb, and 2, 16, and 23 Mar). Treatments of CME 13406 applied once before and at heading and at 3 wk intervals thereafter were made on 3 dates (2 and 24 Feb, and 16 Mar). Applications were made using a tractor-mounted single-bed boom sprayer that operated at 250 psi and delivered 100 gal/acre through 5 D-4, #24 disc disc type cone nozzles at 3 mph. The numbers of small, medium, and large larvae and pupae of diamondback moth (DBM), parasitized DBM pupae, beet armyworm (BAW) larvae, and cabbage budworm (CBW) larvae were recorded on 8 plants/replicate on 10 dates. Foliage injury was rated on 8 plants/replicate on 27 Mar and 2 Apr, and on 24 plants/replicate at harvest (4 Apr), using a scale from 1°6 (1 = no apparent insect feeding, 6 = severe damage to head and wrapper leaves). Percentages of marketable heads were determined for ratings ≤ 3.

Management of Lepidopterous Pests on Cabbage, 1989

Abstract ‘Rio Verde’ cabbage seeds were incorporated into a germination mix (Pro-Mix) and direct seeded at the University of Florida’s Tropical Research and Education Center on 1 Feb ‘89. Plants were spaced 1 ft apart within rows and 30 inches apart between rows on 72 inch center beds. Treatments were replicated 4 times in a randomized complete block design. Treatment plots were 4 rows (2 beds) by 40 ft long. A 10-ft long section of nontreated plants separated replicates; treatments within a replicate were separated by one nontreated bed and a 6 ft alleyway. Applications were made on 3, 10, 16, 23, and 31 Mar and 11, 20, and 28 Apr using a tractor-mounted single-bed boom sprayer that operated at 250 psi and delivered 100 gal/acre through 5 D-4, #24 disc type cone nozzles at 3 mph. All treatments were applied in water. The numbers of small, medium, and large larvae and pupae of diamondback moth (DBM), parasitized DBM pupae, small, medium, and large larvae of beet armyworm (BAW), and small and large larvae of cabbage budworm (CBW) were recorded on 8 plants/replicate, on 7 dates. Foliage injury was rated on 24 plants/replicate using a scale from 1°6 (1 = no apparent insect feeding, 6 = severe damage to head and wrapper leaves). Percentages of marketable heads were determined for each of 2 quality levels, ratings ⁤ 2 and ⁤ 3.

Effect Insecticides on Lepidopter and Leafminers on Tomatoes, 1987:

Abstract Seedlings were transplanted in a sandy loam type soil on 7 Jul at the University of California’s South Coast Field Station in Santa Ana. Experimental plots were 4 rows wide (5-ft centers) by 40 ft long and separated by a 5-ft buffer. The tomato transplants were sprinkle irrigated for 1 wk and drip irrigated thereafter (water pH 7.2-7.5). Treatments were replicated 4 times in a randomized complete block design. Weekly applications were initiated at first fruiting. Application dates were 7, 20, and 27 Aug; 3, 10, 17, and 14 Sep; and 1 and 8 Oct. A tractor-mounted boom sprayer with 4-6 nozzles/row (as plant height and density increased) incorporated D-3 orifice disks, 23-25 cores, and 50-mesh screens. Operating pressure was 100 psi delivering 100 gal/acre. Spreader-sticker (Leaf Act 80) was included for some treatments at 0.04%. Leafminer populations were evaluated by weekly counts of leafminer prepupae and pupae in 4 9- by 11-inch trays/replicate from 26 Aug through 7 Oct. On 14 and 15 Oct, 200 mature green to ripe fruit were harvested from the center 2 rows of each replicate (800/treatment) and examined for internal damage (primarily tomato fruit worm) and external damage (primarily beet army worm) and for tomato pinworm.