Control Of Blue Mold Research Articles

Controlling Tobacco Aphids on Flue-Cured Tobacco, 1996

Abstract Flue-cured tobacco, variety K-326, was transplanted on 10 Apr at the Georgia Coastal Plain Experiment Station Bowen Farm. Production practices were used according to Georgia Cooperative Extension Service guidelines and included a preplant tank mixture of Tillam and Devrinol for weed control, Ridomil for blue mold control, and Nemacur for nematode suppression. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 pounds of acre. Plots 2 rows wide (44-inch row spacing) by 20 ft long were arranged in a RCBD with 4 replications. Plots were separated on each side with one fallow border row and on each end with a 6 ft wide alley. Two Orthene attransplant treatments were applied in the transplant water at transplanting. On 30 May, 9 foliar insecticide treatments were applied using a CO2-powered backpack sprayer equipped with three TX-12 nozzles directed over a single row, delivering 24.5 gpa at 40 psi. The number of live aphids on plants 2, 4 and 6 of the second row was recorded from each plot prior to treatment (Pre-t) and 4,7,14 and 21 days after treatment (DAT). Plants 2-11 on the second row were harvested on 21 Jun and cured weights determined by factoring out the moisture content. All data were subjected to analysis of variance and the means were separated using Duncan’s multiple range test (P = 0.05).

Tobacco Budworm and Hornworm Control in Flue-Cured Tobacco, 1996

Abstract Full-Season Test. In Test 1, flue-cured tobacco, variety K-326, was transplanted on 10 Apr at the Georgia Coastal Plain Experiment Station Bowen Farm. Production practices were used according to Georgia Cooperative Extension Service guidelines and included a preplant tank mixture of Tillam and Devrinol for weed control, Ridomil for blue mold control, and Nemacur for nematode suppression. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots, two rows wide (44-inch row spacing) by 25 ft long, were arranged in a RCBD with 4 replications. Plots were separated on each side with a fallow border row and on each end with a 6-ft wide alley. On 31 May, 9 insecticide treatments were applied using a CO2 powered backpack sprayer equipped with three TX-12 nozzles directed over a single row, delivering 24.5 gpa at 40 psi. The number of live budworms and hornworms on all plants of both rows were recorded from each plot prior to treatment (pre-t) and 3,7,10 and 14 days after treatment (DAT). Plants 2-11 on the second row were harvested on 21 Jun and cured weights were determined by factoring out the moisture. All data were subjected to analysis of variance and the means were separated using DMRT. In Test 2, the K-326 tobacco used in Test 1 was striped of all leaves on 21 Jun, the stalks chopped down to a height of about 20 inches and allowed to regrow. This tobacco was side dressed with 16-0-0 at 100 lb/a after chopping. The plot size, randomization, and design remained the same as in trial 1. On 16 July, pre-treatment counts were made and the 9 treatments plus 2 TD 2344 treatments were applied on the regrowth tobacco. The number of live budworms and hornworms on all plants was recorded from each plot 3,7,10 and 15 DAT. The percent defoliation was visually determined for all plants in each plot on 25 and 31 Jul. All data were analyzed with an analysis of variance (P = 0.05).

Tobacco Aphid Control in Flue-Cured Tobacco, 1996

Abstract Flue-cured tobacco, variety K-326, was transplanted on 11 Apr 1996 at the Georgia Coastal Plain Experiment Station Entomology Farm. Production practices were used according to Georgia Cooperative Extension Service guidelines and included a preplant tank mixture of Tillam and Devrinol for weed control, Ridomil for blue mold control, Lorsban for soil insect control, and Nemacur for nematode suppression. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 pounds/acre. Plots two rows wide (36 inch row spacing) by 20 ft long were arranged in a randomized complete block design with four replications. Plots were separated on each side with one un-treated border row and on each end with an alley 6 ft wide. Two Orthene at transplant treatments were applied in the transplant water at transplanting. On 27 May, 4 foliar insecticide treatments were applied using a CO2-powered backpack sprayer equipped with 3 TX-12 nozzles directed over a single row, delivering 29.9 gpa at 40 psi. The number of live aphids on plants 2, 4 and 6 of the left hand row was recorded from each plot prior to treatment (Pre-t) and 4,7 and 14 days after treatment (DAT). All plants were harvested on 17 Jun and 25 Jun, then weighed. All data were subjected to analysis of variance and the means were separated using Duncan’s multiple range test (P = 0.05).

Postharvest Biological Control of Blue Mold of Apple and Brown Rot of Sweet Cherry by Natural Saprophytic Yeasts Alone or in Combination with Low Doses of Fungicides

Abstract Six yeast strains isolated from the surface of pear fruits were evaluated for their ability to control postharvest blue mold (caused by Penicillium expansum ) on Golden Delicious apple fruits. All strains significantly reduced blue mold incidence and severity when applied simultaneously with the pathogen. Cryptococcus infirmo-miniatus strain YY6 and Cryptococcus laurentii strain HRA5 were the most effective, and populations in apple wounds increased approximately 1.2 log units within 10 days at 0°C and approximately 1.4 log units in 2 days at 5, 10, or 20°C. Control of blue mold by these two yeasts alone or in combination with a low dose of thiabendazole (15 μg/ml) was tested at 5, 10, and 20°C. Yeasts combined with thiabendazole controlled the disease significantly better at all temperatures (except at 10°C during 1994) than the low dose of thiabendazole alone, and the control was comparable to that achieved using a commercially recommended high dose of thiabendazole (525 μg/ml). C. infirmo-miniatus controlled disease incidence better than C. laurentii at 5, 10, and 20°C during 1993 and 1994. On sweet cherry, C. infirmo-miniatus or C. laurentii combined with a low dose (20 μg/ml) of iprodione controlled brown rot caused by Monilinia fructicola as did a high dose (1175 μg/ml) of iprodione.

Ecological Diversity, Niche Overlap, and Coexistence of Antagonists Used in Developing Mixtures for Biocontrol of Postharvest Diseases of Apples

A method was developed to select antagonists to be combined in mixtures that controlled blue mold of apple better than individual antagonists alone. Microorganisms selected for these mixtures were isolated from exposed apple tissue at weekly intervals over 5 weeks before harvest. The isolated microorganisms were classified and grouped into various nutritional clusters on the basis of their utilization of 95 carbon sources in Biolog plates using MicroLog and MLCLUST programs, respectively. Yeasts dominated isolations on nutrient yeast-dextrose agar at all isolation times. Bacteria were isolated only occasionally. Isolates were screened for their ability to control blue mold caused by Penicillium expansum on Golden Delicious apple fruit. The most promising antagonists from different clusters were paired in subsequent tests to control blue mold, with preference given to antagonists colonizing the same fruit, secondly to those colonizing different fruit, but isolated at the same time, and finally to those colonizing different fruit at different times of isolation. Among 21 yeast antagonists tested in 13 combinations, four combinations were superior to individual antagonists. In a more extensive test, control of blue mold by a combination of antagonist isolates T5-D3 and T5-E2 was consistently superior to the individual isolates. Nutritional profiles of these antagonists, based on utilization of 35 carbon and 33 nitrogen sources, revealed significant differences in carbon catabolism. These differences caused niche differentiation and allowed populations of both antagonists to flourish in the same wound. De Wit replacement series revealed a high level of coexistence between the two antagonists. This was further confirmed by the relative yield that was close to unity at all antagonist proportions tested. Combining antagonists on the basis of niche differentiation was an effective method of improving control of postharvest blue mold, and probably also for other pre- and postharvest diseases.

Control of Late Season Hornworms in Georgia Flue-Cured Tobacco, 1995

Abstract Flue-cured tobacco, CV K-326, was transplanted on 3 Apr at the Coastal Plain Experiment Station in Tifton, GA. Production practices were used according to Georgia Cooperative Extension Service guidelines. A pre-plant incorporated tank mix of the following was applied: Tilliam and Devrinol for weed control, Ridomil for blue mold control, Nemacur for nematode suppression, and Lorsban for wireworm and mole cricket control. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots 4 rows wide (36 inch row spacing) by 20 feet long were arranged in a RCB design with 4 replications. On 10 Jul, all plants in each plot were cut down to a 12 inch mainstalk, all leaves were removed, and 100 lb/acre of additional nitrogen (16-0-0) was applied. All cut plants were then allowed to regrow with 2-3 main shoots. On 25 Jul, 5 insecticide treatments (plus an untreated control) were applied to the center 2 rows of selected plots using a CO2-powered backpack sprayer equipped with 3, TX-12 nozzles directed over a single row, delivering 22.6 gpa at 40 psi. The number of live hornworms was recorded per 5 plants on row 2 of each plot prior to the application, and 5, 9, and 13 d after this spray. The percent defoliation was visually estimated 10 d after treatment. All data were subjected to ANOVA and Duncan’s multiple range tests (P = 0.05).

Control of Hornworms and Budworms and the Impact on Tobacco Aphid in Georgia Flue-Cured Tobacco, 1994

Abstract Flue-cured tobacco, CV ‘K-326’, was transplanted on 22 Mar, 1994 at the Coastal Plain Experiment Station in Tifton, GA. Production practices were used according to Georgia Cooperative Extension Service guidelines. A pre-plant incorporated tank mix of the following was applied: Tillam and Devrinol for weed control, Ridomil for blue mold control, Nemacur for nematode suppression, and Lorsban for wireworm and mole crickei control. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots, 4 rows wide (44 inch row spacing) X 50 ft, were arranged in a RCBD with 4 replications. In early Jun, all plants in each plot were cut down to an eighteen inch mainstem and all leaves were removed. All cui plants were then allowed to regrow with 2-3 main suckers. On 14 Jun, additional nitrogen (16-0-0) was applied at a rate of 100 lb/acre. On 28 Jun. nine insecticide treatments (plus an untreated control) were applied to the first 3 rows of selected plots using a CO2-powered backpack sprayer equipped with 3 TX-12 nozzles directed over a single row, delivering 23.2 gpa at 40 psi. The number of live homworms and budworms was recorded per 20 plants from the center row of each plot prior to application, and 3, 7, 14, and 21 DAT. Aphid populations also were recorded on plants 2, 4, and 6 of the center row on each sampling date. On 26 Jul, plants 2-9 on the center row were visually examined for both hornworm and budworm defoliation. All data were subjected to ANOVA and Duncan’s multiple range tests.

Late Season Control of Hornworms in Ga Flue-Cured Tobacco, 1994

Abstract Flue-cured tobacco, CV ‘K-326’, was trans-planted on 29 Mar at the Coastal Plain Experiment Station in Tifton, GA. Production practices were used according to Georgia Cooperative Extension Service guidelines. A pre-plant incorporated tank mix of the following was applied: Tillam and Devrinol for weed control, Ridomil for blue mold control, Nemacur for nematode suppression, and Lorsban for wireworm and mole cricket control. Fertilizer (6-6-18) was applied in a split application at a rate of 0.5 ton/acre. Plots 4 rows wide (44 inch row spacing) X 20 ft long were arranged in a RCB design with 4 replications. On 11 Jul, all plants in each plot were cut down to a 12 inch mainstalk, all leaves were removed, and 100 lb/acre of additional nitrogen (16-0-0) was applied. All cut plants were then allowed to regrow with 2-3 main shoots. On 26 Jul, 9 insecticide treatments (plus an untreated control) were applied to the center 2 rows of selected plots using a CO2-powered backpack sprayer equipped with three TX-12 nozzles directed over a single row, delivering 23.2 gpa at 40 psi. The granular materials were hand applied on all available foliage. The number of live hornworms was recorded per 5 plants on row 2 of each plot prior to the application, and 3, 7, and 10 d after treatment (DAT). The percent defoliation was visually estimated 10 DAT. All data were subjected to ANOVA and DMRT (P = 0.05).

Biocontrol of postharvest diseases of apple usingBacillusspp. isolated from stored apples

Ninety-five bacterial isolates were recovered from 38 of 77 apples that had been stored at 1 °C for 6–7 months. The highest number of bacteria were recovered in nutrient, dextrose, and V8 juice broths, respectively. The bacteria were screened as biocontrol agents on cultivar Red Delicious apples primarily for control of blue mold caused by Penicillium expansum. Three bacteria effective against P. expansum were also tested against Botrytis cinerea for control of gray mold. Ten, four, and five isolates significantly reduced blue mold decay when apples were stored at 5, 10, and 20 °C. Two isolates tested against gray mold decay significantly reduced decay at 5 and 10 °C and one isolate was effective at 20 °C. Thirty-six isolates that had been selected for identification by the Biolog Microstation™ System were Gram positive and contained endospores, and 30 of these were positively identified as Bacillus spp. Further testing of 15 isolates that were effective biocontrol agents identified 7 as Bacillus subtilis on the basis of 15 microbiological tests used for determining species within the genus Bacillus.Key words: endophytic, bacteria, biocontrol, postharvest.

Controlling Aphids in Georgia Flue-Cured Tobacco with Foliar Insecticides, 1993

Abstract Flue-cured tobacco was transplanted on 9 Apr at the Coastal Plain Experiment Station in Tifton, GA. Production practices were carried out according to Georgia Cooperative Extension Service recommendations. A pre-plant incorporated tank mix of the following was applied; Tillam and Devrinol for weed control, Ridomil for blue mold control, and Nemacur for nematode suppression. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots 3 rows wide (36 inch row spacing) × 20 ft long were arranged in a RCBD with 4 replications. Seven insecticide treatments (plus an untreated check) were applied on 31 May to control an aphid population that averaged around 500 per 3 plants (4 upper leaves). The foliar sprays were applied with a CO2-powered backpack sprayer equipped with three TX-12 nozzles directed over a single row, delivering 30 gpa at 40 psi. Each plot was separated by an untreated border row and a 4 ft alley on each end. The number of live aphids on the 4 uppermost leaves was recorded on plants 3, 4 and 6 on row 2 of each plot prior to application and 3, 7, and 14 DAT. On each sampling date the number of live tobacco budworms also was recorded from 8 plants on row 2 of each plot. On 6 and 12 Jul, 8 plants on row 2 were harvested and yield estimates obtained. Data were subjected to ANOVA and Duncan’s Multiple Range Test

Control of Hornworms in Georgia Flue-Cured Tobacco, 1993

Abstract Flue-cured tobacco was transplanted on 29 Mar at the Coastal Plain Experiment Station in Tifton, GA. Production practices were used according to Georgia Cooperative Extension Service guidelines. A preplant incorporated tank mix of the following was applied: Tillam and Devrinol for weed control, Ridomil for blue mold control, Nemacur for nematode suppression, and Lorsban for wireworm and mole cricket control. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots 4 rows wide (44 inch row spacing) × 20 ft long were arranged in a RCBD with 4 replications. On 9 Jul all plants in each plot were cut down to a 12 inch mainstalk and all leaves were removed. All cut plants were then allowed to regrow with 2-3 main shoots. On 23 Jul, 5 insecticide treatments (plus an untreated control) were applied to the center 2 rows of selected plots using a CO2-powered backpack sprayer equipped with three TX-12 nozzles directed over a single row, delivering 30.3 gpa at 40 psi. The number of live hornworms was recorded per 10 plants on row 2 of each plot prior to the application, and 5, 10, and 14 DAT. All data were subjected to ANOVA and Duncan’s Multiple Range Test.

Budworm and Aphid Control in Georgia Flue-Cured Tobacco, 1993

Abstract Flue-cured tobacco, CV K-326’, was transplanted on 6 Apr at the Coastal Plain Experiment Station, Tifton, GA. Production practices were carried out according to Georgia Cooperative Extension Service recommendations. A pre-plant incorporated tank mix of the following was applied: Tillam and Devrinol for weed control, Ridomil for blue mold control, and Nemacur for nematode suppression. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots 3 rows wide (36 inch row spacing) × 20 ft long were arranged in a RCBD with 4 replications. Seven insecticide treatments, plus an untreated control, were applied on 4 weekly intervals in Test 1 beginning on 14 May and continuing until 4 Jun to control tobacco budworms that averaged around 3 worms per 8 plants. The foliar sprays were applied with a CO2-powered backpack sprayer equipped with three TX-12 nozzles directed over a single row, delivering 30.3 gpa at 40 psi. Each plot was separated by an untreated border row and an alley 4 ft wide on each end. The number of live small, medium, and large tobacco budworms per 8 plants on row 2 of each plot was recorded prior to treatment and 4 and 7 DAT. The number of live aphids on the 4 uppermost leaves was recorded on plants 2, 4 and 6 on row 2 of each plot on each sampling date. The number of live thrips was recorded on plant 6 on row 2 of each plot on each sampling date in May, then these counts were discontinued due to low population densities. Budworm damage ratings (% defoliation) also were taken on 14 Jun. Beginning on 1 Jul the lower leaves on 8 plants on row 2 were harvested. A total of 4 harvests (primings) was gathered from each plot and yield estimates and quality ratings were obtained. All data were subjected to ANOVA. In this same field of tobacco additional plots were cut back to 1 ft stalks and all leaves removed on 1 Jul. This tobacco was allowed to regrow (2-3 main suckers per plant). On 14 Jul, 11 insecticide treatments plus an untreated control were applied to plots 3 rows wide × 20 ft long arranged in a RCBD with 4 replications, using application techniques previously described. All treatments were reapplied on 22 Jul. The number of live budworms and hornworms per 8 plants on row 2 of each plot was recorded prior to treatment and 5 and 8 DAT following the 1st applications and 5, 8, and 14 DAT following the second applications. Budworm and hornworm defoliation ratings were obtained on 5 Aug. All data were subjected to ANOVA.

Aphid and Budworm Control in Tobacco, 1992:

Abstract Flue-cured tobacco was transplanted on 31 Mar at the Coastal Plain Experiment Station in Tifton, GA. Production practices were used according to Georgia Cooperative Extension Service guidelines. A pre-plant incorporated tank mix of the following was applied; Tillam and Devrinol for weed control, Ridmil for blue mold control, Nemacur for nematoda suppression, and Lorsban for wireworm and mole cricket control. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots 4 rows wide (44 inch row spacing) by 20 ft long were arranged in a RCB design with 4 replications. On 15 May, 2 insecticide treatments (Sevine and Orthene) plus an untreated control were applied to the center 2 rows of selected plots using a CO2-powered backpack sprayer equipped with 3 TX-9 nozzles directed over a single row, delivering 13.7 gal/acre at 40 psi. On 27 May, these 2 treatments plus 6 additional treatments were applied as previously described. Each of the 8 treatments was reapplied on 3 Jun. Prior to tbe 27 May application, and 3 and 6 d after the first spray and 5 and 8 d after the 2nd spray, the number of live aphids and thrips on plants 2, 4 and 6 on row 2 was recorded. Also on these dates, the number of budworms were counted per 10 plants on row %. All data were subjected to ANOVA and DMRT (P = 0.05).

Budworm and Aphid Control in Tobacco, 1992:

Abstract Flue-cured tobacco was transplanted on 16 Mar at the Coastal Plain Experiment Station in Tifton, GA. Production practices were used according to Georgia Cooperative Extension Service guidelines. A pre-plant incorporated tank mix of the following was applied. Tillam and Devrinol for weed control, Ridomil for blue mold control, Nemacur for nematode suppression, and Lorsban for wireworm and mole cricket control. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots 4 rows wide (36 inch row spacing) by 20 ft long were arranged in a RCB design with 4 replications. On 11 Jun, 11 insecticide treatments (plus an untreated control) were applied to the center 2 rows of selected plots using a CO2-powered backpack sprayer equipped with 3 TX-9 nozzles directed over a single row, delivering 13.7 gal/acre at 40 psi. Each treatment was reapplied on 18 Jun. Prior to the initial application, and 4 and 7 d after each treatment (DAT), the number of live budworms was recorded per 8 plants on row 2 of each plot. The number of live aphids on the 4 upper leaves on plants 2,4, and 6 on row 2 also was recorded. All data were subjected to ANOVA and DMRT (P = 0.05).

Aphid Control in Georgia Flue-Cured Tobacco, 1991

Abstract Flue-cured tobacco, 'Speight G-70', was transplanted on 29 Mar at the Coastal Plain Experiment Station in Tifton, GA. Production practices were carried out according to Georgia Cooperative Extension Service recommendations. A preplant incorporated tank mix of the following was applied: Tillam and Devrinol for weed control, Ridomil for blue mold control, Nemacur for nematode suppression, and Lorsban for wireworm and grub control. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots 4 rows wide (36- inch row spacing) by 20 ft long were arranged in a randomized complete block design with 4 replications of nine insecticide treatments (plus an untreated check). Treatments were applied on 13 May to control an aphid population that averaged around 500 per plant (4 upper leaves). The foliar sprays were applied with a CO2-powered backpack sprayer equipped with 3, TX-12 nozzles directed over a single row, delivering 27 gal/acre at 35 psi. Each plot was separated by an untreated border row and a 4 ft alley on each end. The number of live aphids on the 4 uppermost leaves was recorded on plants 2, 4, and 6 on row 2 of each plot prior to application and 3, 7, and 14 DAT. Aphid damage ratings also were taken on 3 Jun from each of the 8 plants in row 2 of each plot. Damage scores ranged from 0 (no visible aphid damage) to 10 (all upper leaves essentially covered with aphids, honeydew, and sooty mold). The number of thrips, flea beetles, hornworms, and budworms on plants 2, 4, and 6 also were recorded 14 DAT. On 12 Jun, the 8 plants on row 2 were harvested and yield estimates obtained. DATA were subjected to ANOVA and Duncan's multiple range test (P = 0.05).

Thrips Control in Georgia Flue-Cured Tobacco, 1991

Abstract Flue-cured tobacco, K-326, was transplanted on 12 April at the Coastal Plain Experiment Station Bowen Farm in Tift County, GA. Production practices followed recommendations of the Georgia Cooperative Extension Service, and included Tillam and Devrinol for weed control, Lorsban for wireworms and grubs, Nemacur for nematode suppression, and Ridomil for blue mold control. Fertilizer (6-6-18) was applied at a rate of 1000 lb/acre in a split application. Plots 4 rows wide (44 inch row spacing) by 30 ft long were arranged in a randomized complete block design with 4 replications of four insecticide treatments (plus an untreated control). Treatments were applied on 18, 26 Apr, 2, and 10 May to control thrips. Foliar sprays were applied with a CO2-powered backpack sprayer equipped with 3, TX-12 nozzles directed over a single row, delivering 27 gal/acre at 35 psi. Each plot was separated by an untreated border row and an alley 4 ft wide on each end. The number of live thrips on plants 2, 4, and 6 of row 2 were counted on 22 Apr, 2, and 10 May prior to applying treatments, and on 13 and 27 May. The aphids per 10 plants in row 2 also were counted on these dates. All data were subjected to AN OVA and Duncan's multiple range test (P = 0.05).

Controlling Tobacco Insect Pests with Transplant and Foliar Insecticide Treatments, 1991

Abstract Flue-cured tobacco, 'CV K-326', was transplanted on 12 Apr at the Coastal Plain Experiment Station Bowen Farm in Tift County, GA. Production practices were carried out according to Georgia Cooperative Extension Service recommendations. A pre-plant incorporated tank mix of the following was applied; Tillam and Devrinol for weed control, Ridomil for blue mold control, and Nemacur for nematode suppression. Fertilizer (6-6-18) was applied at a rate of 1000 lb/acre in a split application. Prior to planting, plots 4 rows wide (44 inch row spacing) by 20 ft long were arranged in a randomized complete block design with 4 replications. Six transplant insecticide treatments were applied at planting and included NTN 33893 in the transplant water, NTN 33893 as a foliar spray after transplant, Orthene in the transplant water, Orthene as a foliar spray after transplant, Temik in a 6-inch band to the side of the row and incorporated after transplant, and Furadan in an incorporated band after transplant. Also, Orthene was foliar-applied at 2 and 4 wk after transplant. The eighth treatment was an untreated control. Transplant water treatments were applied at a rate of 4 oz of form per plant. Foliar sprays were applied with a CO2-powered backpack sprayer equipped with 3, TX-12 nozzles directed over the row, delivering 22 gal of form/acre at 35 psi. Granular materials were applied with a Gandy applicator as sidedress applications in a 6-inch band to the right of the row and lightly incorporated. The center 2 rows of each plot were treated with an untreated border row on each side. All plots were separated on each end with an alley 4 ft wide. The number of live aphids and thrips was recorded on plants 2, 4, and 6 of row 2 of each plot 10, 21, 40, and 70 days after transplant. Also, the number of budworms and hornworms per 10 plants was recorded on these same sampling dates. Aphid damage ratings were taken on 27 Jun from each of the 10 plants in row 2 that were being used to determine yield estimates. Damage scores ranged from 0 (no visible aphid injury) to 10 (all upper leaves essentially covered with aphid injury, honeydew, and sooty mold). Also on 27 Jun each of the 10 plants were visually rated for percent defoliation. Between mid-Jun and late Jul each plot was harvested (4 primings) and cured. All data were subjected to ANOVA and Duncan's multiple range test (P = 0.05).

Budworm and Hornworm Control in Tobacco, 1991

Abstract Flue-cured tobacco, 'CV K-326", was transplanted on 28 Mar at the Coastal Plain Experiment Station in Tifton, GA. Production practices were used according to Georgia Cooperative Extension Service guidelines. A pre-plant incorporated tank mix of the following was applied: Tillam and Devrinol for weed control, Ridomil for blue mold control, Nemacur for nematode suppression, and Lorsban for wireworm and mole cricket control. Fertilizer (6-6-18) was applied in a split application at a rate of 1000 lb/acre. Plots 4 rows wide (36-inch row spacing) by 20 ft long were arranged in a randomized complete block design with 4 replications. Because budworm and hornworm populations were low at this test site during the regular growing season, all plots were cropped in early Jun and one main sucker was allowed to regrow. On 21 Jun, 9 insecticide treatments (plus an untreated control) were applied to the center 2 rows of selected plots using a CO2-powered backpack sprayer equipped with three TX- 12 nozzles directed over a single row, delivering 28.6 gal/acre at 40 psi. Each treatment was reapplied on 8 Jul. Prior to the initial application, and 3, 7, and 12 d after the first spray and 3, 7, and 14 d after the second spray, the number of live budworms and hornworms was recorded per 8 plants on row 2 of each plot. The number of live aphids also was recorded from the 8-plant samples on these dates. All data were subjected to ANOVA and DMRT (P=0.05).

Factors affecting the efficacy of post‐harvest fungicide applications for the control of blue mould (Penicillium expansum) in stored apples

The effects of apple fruit maturity, temperature of fruit or dip solution, period of time in fungicidal dip, storage conditions, and spore inoculum concentration, on the efficacy of fungicides for control of blue mould (Penicillium expansum) were examined in various experiments.Iprodione and imazalil were only effective when inoculum concentration was low, whilst prochloraz was highly effective in controlling rot on fruit inoculated with 3 × 106 spores/ml. There was no consistent effect of dip temperature or fruit maturity on the efficacy of the fungicides. Iprodione was more effective on warm fruit (19°C) than cold fruit (6°C) whilst the reverse was true of imazalil. Extended periods of immersion in the fungicides slightly reduced the incidence of rotting but not to any useful degree.The incidence of rotting in fruit treated with prochloraz and etaconazole was less in fruit stored under controlled‐atmosphere cold storage conditions than in fruit stored in air cold‐storage. Both fungicides were also effective for short‐term storage at 20 C in air. Captan, benomyl, captan plus benomyl or vinclozolin were either ineffective or of poor efficacy under all storage conditions.

Efficacy of Fungicides Applied at Various Times in Relation to Inoculation for Control of Blue Mould in Apples Caused by Penicillium Expansum.

The fungicides imazalil and prochloraz were effective against blue mould infection of apples when applied as a dip before or after inoculation, or when incorporated in a dip solution containing spores. Prochloraz was highly effective at all spore concentrations tested, but the efficacy of imazalil decreased with increasing spore concentration.