Search Results

You are looking at 1 - 10 of 32 items for :

  • "sulfur dioxide" x
  • Journal of the American Society for Horticultural Science x
Clear All

Three watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] cultivars with different ozone (O3) sensitivities were grown in a charcoal-filtered greenhouse and exposed in continuous-stirred tank reactor chambers to five levels (0, 100, 200, 300, or 400 nL·L-1) of sulfur dioxide (SO2) in the presence (80 nL·L-1) or absence (0 nL·L-1) of ozone (O3) for 4 hours/day, 5 days/week for 22 days. In the presence of O3, SO2 increased foliar injury in all three cultivars, but the impact was greatest for the most O3-sensitive cultivar, `Sugar Baby,' moderate for `Crimson Sweet,' and least for the least O3-sensitive cultivar, `Charleston Gray.' For all cultivars, SO2 intensified O3 suppression of leaf area for the first seven mainstem leaves and of dry weights for aboveground and total plant tissues. Root dry weight was independently suppressed by both pollutants, and the root: top ratio was linearly suppressed by SO2 alone. Sulfur dioxide combined with O3 can be detrimental to crop species such as watermelon. Thus, the potential for SO2 phytotoxicity should not be summarily dismissed, especially in the vicinity of SO2 point sources where O3 co-occurs.

Free access

Three-year-old `Valencia' orange [Citrus sinensis (L.) Osbeck] trees were exposed to air pollutants for 4. years in open-top field chambers to determine the chronic effects of ambient oxidants (primarily ozone) or sulfur dioxide (SO2) on fruit yield and quality and tree growth. Ozone concentrations averaged 0.012,0.040, and 0.075 ppm for 0800 to 2000 hr during April to October for filtered, half-ambient, and full ambient oxidant chambers. Sulfur dioxide was applied continuously at 0.09 ppm. Oxidant and SO2 effects were only marginally significant, as there was considerable variability in response among individual trees and between years. Across two “on” production years, yields were 31% lower with ambient oxidants, 11% lower with half-ambient oxidants, and 29% lower with sulfur dioxide compared to filtered air. Number of fruit per tree was reduced by ambient oxidants and SO2. Individual fruit weights were reduced by ambient oxidants, but no other fruit quality characteristics showed definite responses to ambient oxidants or SO2. Ambient oxidants had no effect on yield or quality of fruit during one “off' production year. Neither ambient oxidants nor SO, affected tree growth.

Free access

Abstract

The radish cv. Cherry Belle was exposed to 5 pphm ozone and/or 5 pphm sulfur dioxide for 40 hr per week for 5 weeks and compared with controls grown in charcoal filtered air. Ozone and/or sulfur dioxide significantly reduced the plant fresh wt, leaf fresh wt, root fresh and dry wt and root length and width. The effects of the combinations of the 2 gases were additive except for plant fresh wt, root length and root fresh and dry weights where the effects were significantly less than additive. Low concns of ozone and sulfur dioxide can be significant factors in the growth and yield of radishes.

Open Access

Abstract

Three separate experiments were conducted in a mature Vitis labruscana Bailey ‘Concord’ vineyard in New York to determine the response of grapevines to daily, season-long sulfur dioxide (SO2) exposure, or to intermittent SO2 exposure simulating emissions from a 1700 MW coal-fired power plant. There was little SO2-induced necrosis on grape foliage from daily or power plant SO2. However, both treatments in ambient air increased susceptibility of leaves to oxidant stipple injury due to ambient ozone (O3). Daily SO2 increased leaf chlorosis. Power plant SO2 had no effect on vine growth, yield, or shoot maturation. Daily SO2 reduced soluble solids, growth, yield, and shoot maturation of grapevines. Damage to grapevines from SO2 seemed to be independent of SO2 induced leaf necrosis. SO2 reduced foliage tolerance to O3 injury in grapevines already stressed by ambient O3.

Open Access

Abstract

No appreciable signs of phytotoxicity were observed for 4 days following fumigation of plants (including begonias, petunias, snapdragons) with ozone of up to 80 parts per hundred million (pphm) or sulfur dioxide of up to 400 pphm for 2 hr. Thereafter, there was considerable necrosis, particularly on begonias fumigated with the highest concn of the pollutants. Growth suppression was reflected in reduced shoot and flower wt, and to a lesser degree in reduced flower number. Overall, begonias and petunias were the most sensitive. Coleus and snapdragons were moderately sensitive, while marigold, celosia, impatiens and salvia were tolerant. ‘White Tausendschon’ was the most sensitive begonia cultivar while blue-flowered ‘Capri’ was the most sensitive petunia. Mixed color petunias exhibited varying degrees of tolerance. ‘Scarlet Rainbow’ coleus was more sensitive than ‘Pastel Rainbow’. Measurements of growth alterations in plants were found very useful in determining latent forms of air pollutant injury.

Open Access

Abstract

Eighteen lines of Euvitis grapes in 1980, and 30 in 1981, were stored for 9 weeks at 0°C in 5.7-liter telescoping, corrugated cardboard shipping containers with polyethylene liners, with and without commercially available sulfur dioxide (SO2) generators (1 in 1980; 2 in 1981). Decay during storage without SO2 varied greatly among lines (2% to 81% in 1980 and 0% to 62% in 1981). The generator producing SO2 for the entire 9 weeks in 1981 eliminated decay of most grape lots. By comparison, the generators producing SO2 for only 2 weeks permitted 4 times as much decay. Two weeks of SO2, however, permitted only one-fifth as much decay as that associated with no SO2 during storage. Both generators reduced degradation of appearance and flavor of the grapes. The long-term generator was associated with more SO2 damage to the fruit than was the short-term generator. The lines varied widely in tolerance to SO2. SO2 damaged the fruit by entering openings in their surfaces caused by stem tears and cracks.

Open Access

Abstract

N-[2-(2-oxo-l-imidazolidinyl)ethyl]-N’-phenylurea, (EDU or ethylenediurea) reduced the sensitivity of petunia plants (Petunia hybrida Vilm.) to ozone when treated with foliar or root applications. For most plants, EDU gave protection from visible injury within 24 hours of its application as a spray or soil drench. It was much more effective than butanedioic acid mono-(2,2-dimethylhydrazide) (daminozide) as a protectant from ozone injury. The activity of EDU was unaffected by the addition of a surfactant to the spray solution or soil drench, by day length, light conditions, temperature, and physiological preconditioning of the plants. Protection from injury by ozone lasted for at least 14 days. Furthermore, a concentration of 500 ppm either as a foliar spray of 1 to 2 ml per plant or as a soil drench of 100 ml per 10-cm diameter pot protected an ozone sensitive cultivar, ‘Snow Magic,’ the moderately sensitive cultivars, ‘White’ and ‘Pink Cascade,’ and the least sensitive cultivars, ‘Comanche Improved’ and ‘Sugar Plum’. Treatment with EDU afforded no protection against sulfur dioxide exposure doses which produced acute injury.

Open Access

Abstract

Three cultivars of greenhouse-grown apple trees (Malus domestica, Borkh.) were fumigated for single, 4-hour exposures with ozone (O3) and/or sulfur dioxide (SO2) at 0.40 and 0.80 ppm. Fumigations were performed in a plexiglass chamber situated within a controlled environment walk-in growth chamber. All 3 cultivars responded to treatments in a similar manner. When applied separately both gases induced characteristic foliar injury. In general, apple trees were more sensitive to 0.40 ppm O3 than to 0.40 ppm SO2; but they responded similarly to 0.80 ppm O3 or SO2. Foliar injury, leaf abscission, and shoot growth reduction were greatest when 0.80 ppm O3 and 0.80 ppm SO2 were combined. The data showed a less-than additive response when the 2 pollutants were combined; a response due, in part, to the high amount of injury induced by single pollutants at these concentrations. All O3 and/or SO2 fumigations resulted in stomatal closure.

Open Access
Authors: and

Abstract

Eighteen cultivars representing 6 species (Poa pratensis L., Agrostis alba L., Agrostis palustris Huds., Agrostis tenuis Sibth., Festuca rubra Gaud., and Lolium perenne L.) of cool season turfgrass were exposed to 15 pphm ozone for 6 hours daily, 15 pphm sulfur dioxide continuously, 15 pphm nitrogen dioxide continuously, or a mixture of all three at these concentrations for 10 days. The most common symptoms of injury on sensitive cultivars in response to these gases were bleaching and necrosis of leaves with some cultivars exhibiting dark brown necrosis and stippling in response to O3 alone. Cultivars varied in sensitivity to O3 or SO2 from very sensitive to insensitive while few cultivars were sensitive to NO2 alone at the concentration used. Exposure of some cultivars resulted in less leaf area production but no visible injury symptoms, while other cultivars had leaf injury without reduction of area of uninjured leaves. The combined exposure caused more leaf injury and greater reduction in the leaf area production by most cultivars compared with plants exposed to single gases. Exposure to single pollutants could provide inaccurate estimates of turfgrass cultivar sensitivity outdoors where several pollutants may occur simultaneously.

Open Access

Abstract

Eight cultivars of poinsettia, Euphorbia pulcherrima Willd., were evaluated for sensitivity to α-cyclopropyl-α (4-methoxyphenyl)-5-pyrimidine methanol (ancymidol) and protection from ozone and sulfur dioxide injury afforded by applications of ancymidol and (2-chloroethyl) trimethyl ammonium chloride (chlormequat). Foliar sprays of ancymidol were at least 80 to 500 times and the soil drench 1000 times more active than chlormequat in retarding stem elongation. The diam of the bracts was reduced, but branching increased more on plants treated with ancymidol than on untreated plants. The cv. Annette Hegg (AH) was more sensitive to ozone fumigations than was ‘Eckespoint C-l’ (C-l). Sulfur dioxide also caused more injury to AH than to C-l. Ancymidol and chlormequat reduced visible injury induced by ozone and sulfur dioxide.

Open Access