Journal of the American Society For Horticultural Science, Jul 1, 1994
14 C-urea penetration of isolated tomato (Lycopersicon esculentum Mill. cv. 'Pik Red') fruit cuti... more 14 C-urea penetration of isolated tomato (Lycopersicon esculentum Mill. cv. 'Pik Red') fruit cuticular membranes (CM) was studied as a function of concentration and temperature. There was no significant effect of cuticular wax on urea penetration at 25C, permeances for the CM being 8.4 × 10 -10 and dewaxed CM (DCM) 11.1 × 10 -10 ·m·s -1 . Time lags were near zero for both CM and DCM. Steady-state diffusion analysis suggests that the relatively low cuticular permeance of urea is due to low partitioning that offsets high diffusivity. Urea flux through the CM and DCM showed ≈1.5and 1.9-fold increases, respectively, for each 10C increase between 5 and 45C. Urea flux across CM and DCM increased linearly with concentration (10 µM to 1 M) and, thus, was a first-order process.
The Abstracts that follow are arranged in numerical sequence by the abstract number. For Poster S... more The Abstracts that follow are arranged in numerical sequence by the abstract number. For Poster Sessions, session numbers (in parentheses) follow the abstract numbers. Example: 003 (PS 1) represents abstract 003 in Poster Session 2; 304 (PS 14) represents abstract 304 in Poster Session 14. .
Journal of the American Society For Horticultural Science, May 1, 1995
The effect of temperature on uptake of 14 C-labeled NAA was determined using detached apple leave... more The effect of temperature on uptake of 14 C-labeled NAA was determined using detached apple leaves. Uptake by both adaxial and abaxial surfaces was measured at 15 and 35C over a 24-hotm period. Foliar absorption of NAA by the abaxial surface was greater than that by the adaxial surface. Absorption by the abaxial surface increased linearly (P < 0.001) with temperature over the range of 15 to 35C. These results are discussed in relation to fruit thinning. Chemical name used: 2-(1-naphthyl)acetic acid (NAA).
The Abstracts that follow are arranged by type of session (Posters first, then Orals, Colloquia, ... more The Abstracts that follow are arranged by type of session (Posters first, then Orals, Colloquia, and Workshops). The Poster abstract numbers correspond to the Poster Board number at which the Poster will be presented.
The Abstracts that follow are arranged in numerical sequence by the abstract number. For Poster S... more The Abstracts that follow are arranged in numerical sequence by the abstract number. For Poster Sessions, session numbers (in parentheses) follow the abstract numbers. Example: 002 (PS II) represents abstract 002 in Poster Session II; 180 (PS VIII) represents abstract 180 in Poster Session VIII.
The Abstracts that follow are arranged by type of session (Posters fi rst, then Orals, Colloquia,... more The Abstracts that follow are arranged by type of session (Posters fi rst, then Orals, Colloquia, and Workshops). The Poster abstract numbers correspond to the Poster Board number at which the Poster will be presented. Cranberry plants exclusively utilize ammonium forms of nitrogen. Nitrifi cation of applied ammonium and subsequent leaching through sandy soils is a potential problem for growers. Peat, sand, and striped soils were collected in cranberry beds in central Wisconsin and soil pH was adjusted to 3.5, 4.5, or 5.5. Twenty-fi ve grams of dry soil was placed in fl asks and half the fl asks were sterilized. Distilled water was added to half of the samples, and the other half received 15 N-labeled ammonium. Flasks were incubated at 20°C for up to 70 days. Striped soils showed no nitrifi cation at pH 3.5 or 4.5 during the 70 day incubation. At pH 5.5, nitrifi cation began at 20 days and was almost complete at 70 days. Nitrifi cation did not occur at any pH in sandy soils. This research suggests that ammonium fertilizer applied to cranberry is likely taken up before nitrifi cation would occur. Annual ryegrass (Lolium multifl orum), which grows prolifi cally during the strawberry production season in the Gulf South, has the potential to serve as a living mulch if its growth is controlled. Sublethal dosages of Embark, a plant growth regulator, and the herbicides Poast and Rely were determined on ryegrass. Growth retardation was rated from 0 = none to 6 = dead. In 1993, all Poast dosages (1/8X -1X, where X = 8 ml•L -1 ) were lethal. Embark regulated ryegrass growth, but its study was discontinued because of the unlikelihood that it could be labeled for use on strawberries. Results of the 1994 study suggested that prime oil in the spray may cause an inordinate amount of vegetative browning. In 1995, three levels of oil (1/256X, 1/64X, and 1/32X, where X = 8 ml•L -1 ) were HORTSCIENCE, VOL. 32(3), JUNE 1997 428 used with each of four levels of Poast (0, 1/32, 1/64, and 1/128X). Increased levels of oil generally caused increased browning at each level of Poast, but no browning occurred where oil only was applied in the spray. In contrast to results in 1995, oil at 1/32X with no Poast caused considerable browning (score = 3.25) in 1996. The most desirable control (score = 2.75) was accomplished by a spray containing 1/128X Poast and 1/64X oil. The most desirable control by Rely (score = 3.25) was accomplished by 1/64 and 1/32X sprays. Rely is not labeled for strawberries although it is labeled for other fruit crops. Chemical names used: 2-[1-(ethoxylmino)buty1]-5-[2-(ethylthio)propy1]-3-hydroxy-2-cyclohexen-1one (Poast); Paraffi n Base Petroleum Oil + polyol Fatty acid Esters (Prime oil); N- [2,4dimethyl-5-[[(trifl uoromethyl)-sulfony]amino]phenyl] acetamide (Embark); ammonium-Dl-homoalanin-4-yl-(methyl) phosphinate (Rely). A fi eld study was conducted to evaluate individual and collective infl uences of three soil moisture-supplementing practices (irrigation, incorporated peatmoss, and mulching) on root system development in 'Gulfcoast' southern highbush blueberries. Root growth was least in plants not mulched and greatest in plants receiving all three supplements. Ranking of individual treatments on root dry weight production was mulch > incorporated peatmoss = irrigation. Mulching resulted in uniform root distribution from the plant crown outward and in root growth concentrated in the upper 15 cm of soil. Other practices (peatmoss > irrigation) tended to concentrate the root system near the crown area and resulted (peatmoss = irrigation) in greater root depth. Soil moisture appeared to be the major factor infl uencing root distribution. Experiments were conducted to determine the temperatures at which different densities of INA bacteria incite ice crystallization on 'Totem' strawberry fl owers and to determine if there is a relationship between densities of INA bacteria on strawberry fl owers and fl oral injury. Primary fl owers were inoculated with Pseudomonas syringae at 10 6 cells/ml buffer, incubated at 25°C day/10°C night and 100% RH for 48 h, and exposed to -2.0°C. No ice nucleation occurred on these inoculated fl owers and all of the fl owers survived. However, when inoculated fl owers were subjected to lower temperatures, ice nucleation occurred at -2.2°C and few of the fl owers survived. In contrast, ice crystals formed on the surface of most non-inoculated fl owers at -2.8°C and 21% of the fl owers survived exposure to -3.5°C. When INA bacterial densities were ≈10 5 colony forming units/g dry wt, fl oral injury occurred at a warmer temperature than to fl owers that had lower bacterial densities. Apartado Postal No. 125, Caborca, Son.
The Abstracts that follow are arranged by type of session (Posters fi rst, then Orals, Colloquia,... more The Abstracts that follow are arranged by type of session (Posters fi rst, then Orals, Colloquia, and Workshops). The Poster abstract numbers correspond to the Poster Board number at which the Poster will be presented. Cranberry plants exclusively utilize ammonium forms of nitrogen. Nitrifi cation of applied ammonium and subsequent leaching through sandy soils is a potential problem for growers. Peat, sand, and striped soils were collected in cranberry beds in central Wisconsin and soil pH was adjusted to 3.5, 4.5, or 5.5. Twenty-fi ve grams of dry soil was placed in fl asks and half the fl asks were sterilized. Distilled water was added to half of the samples, and the other half received 15 N-labeled ammonium. Flasks were incubated at 20°C for up to 70 days. Striped soils showed no nitrifi cation at pH 3.5 or 4.5 during the 70 day incubation. At pH 5.5, nitrifi cation began at 20 days and was almost complete at 70 days. Nitrifi cation did not occur at any pH in sandy soils. This research suggests that ammonium fertilizer applied to cranberry is likely taken up before nitrifi cation would occur. Annual ryegrass (Lolium multifl orum), which grows prolifi cally during the strawberry production season in the Gulf South, has the potential to serve as a living mulch if its growth is controlled. Sublethal dosages of Embark, a plant growth regulator, and the herbicides Poast and Rely were determined on ryegrass. Growth retardation was rated from 0 = none to 6 = dead. In 1993, all Poast dosages (1/8X -1X, where X = 8 ml•L -1 ) were lethal. Embark regulated ryegrass growth, but its study was discontinued because of the unlikelihood that it could be labeled for use on strawberries. Results of the 1994 study suggested that prime oil in the spray may cause an inordinate amount of vegetative browning. In 1995, three levels of oil (1/256X, 1/64X, and 1/32X, where X = 8 ml•L -1 ) were HORTSCIENCE, VOL. 32(3), JUNE 1997 428 used with each of four levels of Poast (0, 1/32, 1/64, and 1/128X). Increased levels of oil generally caused increased browning at each level of Poast, but no browning occurred where oil only was applied in the spray. In contrast to results in 1995, oil at 1/32X with no Poast caused considerable browning (score = 3.25) in 1996. The most desirable control (score = 2.75) was accomplished by a spray containing 1/128X Poast and 1/64X oil. The most desirable control by Rely (score = 3.25) was accomplished by 1/64 and 1/32X sprays. Rely is not labeled for strawberries although it is labeled for other fruit crops. Chemical names used: 2-[1-(ethoxylmino)buty1]-5-[2-(ethylthio)propy1]-3-hydroxy-2-cyclohexen-1one (Poast); Paraffi n Base Petroleum Oil + polyol Fatty acid Esters (Prime oil); N- [2,4dimethyl-5-[[(trifl uoromethyl)-sulfony]amino]phenyl] acetamide (Embark); ammonium-Dl-homoalanin-4-yl-(methyl) phosphinate (Rely). A fi eld study was conducted to evaluate individual and collective infl uences of three soil moisture-supplementing practices (irrigation, incorporated peatmoss, and mulching) on root system development in 'Gulfcoast' southern highbush blueberries. Root growth was least in plants not mulched and greatest in plants receiving all three supplements. Ranking of individual treatments on root dry weight production was mulch > incorporated peatmoss = irrigation. Mulching resulted in uniform root distribution from the plant crown outward and in root growth concentrated in the upper 15 cm of soil. Other practices (peatmoss > irrigation) tended to concentrate the root system near the crown area and resulted (peatmoss = irrigation) in greater root depth. Soil moisture appeared to be the major factor infl uencing root distribution. Experiments were conducted to determine the temperatures at which different densities of INA bacteria incite ice crystallization on 'Totem' strawberry fl owers and to determine if there is a relationship between densities of INA bacteria on strawberry fl owers and fl oral injury. Primary fl owers were inoculated with Pseudomonas syringae at 10 6 cells/ml buffer, incubated at 25°C day/10°C night and 100% RH for 48 h, and exposed to -2.0°C. No ice nucleation occurred on these inoculated fl owers and all of the fl owers survived. However, when inoculated fl owers were subjected to lower temperatures, ice nucleation occurred at -2.2°C and few of the fl owers survived. In contrast, ice crystals formed on the surface of most non-inoculated fl owers at -2.8°C and 21% of the fl owers survived exposure to -3.5°C. When INA bacterial densities were ≈10 5 colony forming units/g dry wt, fl oral injury occurred at a warmer temperature than to fl owers that had lower bacterial densities. Apartado Postal No. 125, Caborca, Son.
Journal of the American Society For Horticultural Science, Jul 1, 1994
14 C-urea penetration of isolated tomato (Lycopersicon esculentum Mill. cv. 'Pik Red') fruit cuti... more 14 C-urea penetration of isolated tomato (Lycopersicon esculentum Mill. cv. 'Pik Red') fruit cuticular membranes (CM) was studied as a function of concentration and temperature. There was no significant effect of cuticular wax on urea penetration at 25C, permeances for the CM being 8.4 × 10 -10 and dewaxed CM (DCM) 11.1 × 10 -10 ·m·s -1 . Time lags were near zero for both CM and DCM. Steady-state diffusion analysis suggests that the relatively low cuticular permeance of urea is due to low partitioning that offsets high diffusivity. Urea flux through the CM and DCM showed ≈1.5and 1.9-fold increases, respectively, for each 10C increase between 5 and 45C. Urea flux across CM and DCM increased linearly with concentration (10 µM to 1 M) and, thus, was a first-order process.
The Abstracts that follow are arranged in numerical sequence by the abstract number. For Poster S... more The Abstracts that follow are arranged in numerical sequence by the abstract number. For Poster Sessions, session numbers (in parentheses) follow the abstract numbers. Example: 003 (PS 1) represents abstract 003 in Poster Session 2; 304 (PS 14) represents abstract 304 in Poster Session 14. .
Journal of the American Society For Horticultural Science, May 1, 1995
The effect of temperature on uptake of 14 C-labeled NAA was determined using detached apple leave... more The effect of temperature on uptake of 14 C-labeled NAA was determined using detached apple leaves. Uptake by both adaxial and abaxial surfaces was measured at 15 and 35C over a 24-hotm period. Foliar absorption of NAA by the abaxial surface was greater than that by the adaxial surface. Absorption by the abaxial surface increased linearly (P < 0.001) with temperature over the range of 15 to 35C. These results are discussed in relation to fruit thinning. Chemical name used: 2-(1-naphthyl)acetic acid (NAA).
The Abstracts that follow are arranged by type of session (Posters first, then Orals, Colloquia, ... more The Abstracts that follow are arranged by type of session (Posters first, then Orals, Colloquia, and Workshops). The Poster abstract numbers correspond to the Poster Board number at which the Poster will be presented.
The Abstracts that follow are arranged in numerical sequence by the abstract number. For Poster S... more The Abstracts that follow are arranged in numerical sequence by the abstract number. For Poster Sessions, session numbers (in parentheses) follow the abstract numbers. Example: 002 (PS II) represents abstract 002 in Poster Session II; 180 (PS VIII) represents abstract 180 in Poster Session VIII.
The Abstracts that follow are arranged by type of session (Posters fi rst, then Orals, Colloquia,... more The Abstracts that follow are arranged by type of session (Posters fi rst, then Orals, Colloquia, and Workshops). The Poster abstract numbers correspond to the Poster Board number at which the Poster will be presented. Cranberry plants exclusively utilize ammonium forms of nitrogen. Nitrifi cation of applied ammonium and subsequent leaching through sandy soils is a potential problem for growers. Peat, sand, and striped soils were collected in cranberry beds in central Wisconsin and soil pH was adjusted to 3.5, 4.5, or 5.5. Twenty-fi ve grams of dry soil was placed in fl asks and half the fl asks were sterilized. Distilled water was added to half of the samples, and the other half received 15 N-labeled ammonium. Flasks were incubated at 20°C for up to 70 days. Striped soils showed no nitrifi cation at pH 3.5 or 4.5 during the 70 day incubation. At pH 5.5, nitrifi cation began at 20 days and was almost complete at 70 days. Nitrifi cation did not occur at any pH in sandy soils. This research suggests that ammonium fertilizer applied to cranberry is likely taken up before nitrifi cation would occur. Annual ryegrass (Lolium multifl orum), which grows prolifi cally during the strawberry production season in the Gulf South, has the potential to serve as a living mulch if its growth is controlled. Sublethal dosages of Embark, a plant growth regulator, and the herbicides Poast and Rely were determined on ryegrass. Growth retardation was rated from 0 = none to 6 = dead. In 1993, all Poast dosages (1/8X -1X, where X = 8 ml•L -1 ) were lethal. Embark regulated ryegrass growth, but its study was discontinued because of the unlikelihood that it could be labeled for use on strawberries. Results of the 1994 study suggested that prime oil in the spray may cause an inordinate amount of vegetative browning. In 1995, three levels of oil (1/256X, 1/64X, and 1/32X, where X = 8 ml•L -1 ) were HORTSCIENCE, VOL. 32(3), JUNE 1997 428 used with each of four levels of Poast (0, 1/32, 1/64, and 1/128X). Increased levels of oil generally caused increased browning at each level of Poast, but no browning occurred where oil only was applied in the spray. In contrast to results in 1995, oil at 1/32X with no Poast caused considerable browning (score = 3.25) in 1996. The most desirable control (score = 2.75) was accomplished by a spray containing 1/128X Poast and 1/64X oil. The most desirable control by Rely (score = 3.25) was accomplished by 1/64 and 1/32X sprays. Rely is not labeled for strawberries although it is labeled for other fruit crops. Chemical names used: 2-[1-(ethoxylmino)buty1]-5-[2-(ethylthio)propy1]-3-hydroxy-2-cyclohexen-1one (Poast); Paraffi n Base Petroleum Oil + polyol Fatty acid Esters (Prime oil); N- [2,4dimethyl-5-[[(trifl uoromethyl)-sulfony]amino]phenyl] acetamide (Embark); ammonium-Dl-homoalanin-4-yl-(methyl) phosphinate (Rely). A fi eld study was conducted to evaluate individual and collective infl uences of three soil moisture-supplementing practices (irrigation, incorporated peatmoss, and mulching) on root system development in 'Gulfcoast' southern highbush blueberries. Root growth was least in plants not mulched and greatest in plants receiving all three supplements. Ranking of individual treatments on root dry weight production was mulch > incorporated peatmoss = irrigation. Mulching resulted in uniform root distribution from the plant crown outward and in root growth concentrated in the upper 15 cm of soil. Other practices (peatmoss > irrigation) tended to concentrate the root system near the crown area and resulted (peatmoss = irrigation) in greater root depth. Soil moisture appeared to be the major factor infl uencing root distribution. Experiments were conducted to determine the temperatures at which different densities of INA bacteria incite ice crystallization on 'Totem' strawberry fl owers and to determine if there is a relationship between densities of INA bacteria on strawberry fl owers and fl oral injury. Primary fl owers were inoculated with Pseudomonas syringae at 10 6 cells/ml buffer, incubated at 25°C day/10°C night and 100% RH for 48 h, and exposed to -2.0°C. No ice nucleation occurred on these inoculated fl owers and all of the fl owers survived. However, when inoculated fl owers were subjected to lower temperatures, ice nucleation occurred at -2.2°C and few of the fl owers survived. In contrast, ice crystals formed on the surface of most non-inoculated fl owers at -2.8°C and 21% of the fl owers survived exposure to -3.5°C. When INA bacterial densities were ≈10 5 colony forming units/g dry wt, fl oral injury occurred at a warmer temperature than to fl owers that had lower bacterial densities. Apartado Postal No. 125, Caborca, Son.
The Abstracts that follow are arranged by type of session (Posters fi rst, then Orals, Colloquia,... more The Abstracts that follow are arranged by type of session (Posters fi rst, then Orals, Colloquia, and Workshops). The Poster abstract numbers correspond to the Poster Board number at which the Poster will be presented. Cranberry plants exclusively utilize ammonium forms of nitrogen. Nitrifi cation of applied ammonium and subsequent leaching through sandy soils is a potential problem for growers. Peat, sand, and striped soils were collected in cranberry beds in central Wisconsin and soil pH was adjusted to 3.5, 4.5, or 5.5. Twenty-fi ve grams of dry soil was placed in fl asks and half the fl asks were sterilized. Distilled water was added to half of the samples, and the other half received 15 N-labeled ammonium. Flasks were incubated at 20°C for up to 70 days. Striped soils showed no nitrifi cation at pH 3.5 or 4.5 during the 70 day incubation. At pH 5.5, nitrifi cation began at 20 days and was almost complete at 70 days. Nitrifi cation did not occur at any pH in sandy soils. This research suggests that ammonium fertilizer applied to cranberry is likely taken up before nitrifi cation would occur. Annual ryegrass (Lolium multifl orum), which grows prolifi cally during the strawberry production season in the Gulf South, has the potential to serve as a living mulch if its growth is controlled. Sublethal dosages of Embark, a plant growth regulator, and the herbicides Poast and Rely were determined on ryegrass. Growth retardation was rated from 0 = none to 6 = dead. In 1993, all Poast dosages (1/8X -1X, where X = 8 ml•L -1 ) were lethal. Embark regulated ryegrass growth, but its study was discontinued because of the unlikelihood that it could be labeled for use on strawberries. Results of the 1994 study suggested that prime oil in the spray may cause an inordinate amount of vegetative browning. In 1995, three levels of oil (1/256X, 1/64X, and 1/32X, where X = 8 ml•L -1 ) were HORTSCIENCE, VOL. 32(3), JUNE 1997 428 used with each of four levels of Poast (0, 1/32, 1/64, and 1/128X). Increased levels of oil generally caused increased browning at each level of Poast, but no browning occurred where oil only was applied in the spray. In contrast to results in 1995, oil at 1/32X with no Poast caused considerable browning (score = 3.25) in 1996. The most desirable control (score = 2.75) was accomplished by a spray containing 1/128X Poast and 1/64X oil. The most desirable control by Rely (score = 3.25) was accomplished by 1/64 and 1/32X sprays. Rely is not labeled for strawberries although it is labeled for other fruit crops. Chemical names used: 2-[1-(ethoxylmino)buty1]-5-[2-(ethylthio)propy1]-3-hydroxy-2-cyclohexen-1one (Poast); Paraffi n Base Petroleum Oil + polyol Fatty acid Esters (Prime oil); N- [2,4dimethyl-5-[[(trifl uoromethyl)-sulfony]amino]phenyl] acetamide (Embark); ammonium-Dl-homoalanin-4-yl-(methyl) phosphinate (Rely). A fi eld study was conducted to evaluate individual and collective infl uences of three soil moisture-supplementing practices (irrigation, incorporated peatmoss, and mulching) on root system development in 'Gulfcoast' southern highbush blueberries. Root growth was least in plants not mulched and greatest in plants receiving all three supplements. Ranking of individual treatments on root dry weight production was mulch > incorporated peatmoss = irrigation. Mulching resulted in uniform root distribution from the plant crown outward and in root growth concentrated in the upper 15 cm of soil. Other practices (peatmoss > irrigation) tended to concentrate the root system near the crown area and resulted (peatmoss = irrigation) in greater root depth. Soil moisture appeared to be the major factor infl uencing root distribution. Experiments were conducted to determine the temperatures at which different densities of INA bacteria incite ice crystallization on 'Totem' strawberry fl owers and to determine if there is a relationship between densities of INA bacteria on strawberry fl owers and fl oral injury. Primary fl owers were inoculated with Pseudomonas syringae at 10 6 cells/ml buffer, incubated at 25°C day/10°C night and 100% RH for 48 h, and exposed to -2.0°C. No ice nucleation occurred on these inoculated fl owers and all of the fl owers survived. However, when inoculated fl owers were subjected to lower temperatures, ice nucleation occurred at -2.2°C and few of the fl owers survived. In contrast, ice crystals formed on the surface of most non-inoculated fl owers at -2.8°C and 21% of the fl owers survived exposure to -3.5°C. When INA bacterial densities were ≈10 5 colony forming units/g dry wt, fl oral injury occurred at a warmer temperature than to fl owers that had lower bacterial densities. Apartado Postal No. 125, Caborca, Son.
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