Search Results
Abstract
Potato plants (Solanum tuberosum L.) were propagated in controlled environments from tubers or stem cuttings and exposed to SO2 and/or NO2. Cultivar, propagation method, and air quality affected intumescence formation on leaves. Tuber-propagated ‘Kennebec’ and ‘Russet Burbank’ plants developed intumescences in clean air, SO2, or NO2, but not in a SO2-NO2 mixture, whereas tuber-propagated ‘Superior’ and ‘Norchip’ had little or no intumescence formation. Cutting-propagated ‘Kennebec’, ‘Russet Burbank’, and ‘Norchip’ plants had no intumescence development. Intumescence development may be related to carbohydrate status of plants and maturity classification of cultivars.
Table grapes cvs. Flame Seedless, Black Monukka and Canadice were fumigated with 2 levels of Deccodione smoke tablets for 30 minutes. Grapes were packed in TKV lugs with Botrytis inoculum planted among the clusters and stored at 0° C for up to 9 weeks. Size of smoke particles was determined. Fruit was evaluated at weekly intervals for decay and quality parameters. Deccodione residues on fruit were determined and found to be within acceptable limits set for this chemical. It was possible to store the grapes for up to 4 weeks at 0° C in good condition. Beyond this period effect of fumigation was lost. There was no bleaching of pigments around the capstem as is seen with sulfur dioxide fumigation. Storage for prolonged periods will necessitate increasing the dose of Deccodione tables and/or repeating the fumigation.
Abstract
The occurrence of solution pockets in brined sweet cherries has increased during the past 15 years. Affected fruits exhibit translucent pockets beneath the epidermis, filled with ruptured cell contents and brine solution. Pockets may occur anywhere in the fruit but are commonly at the suture. Affected fruits sometimes are not firm enough to pass through a pitting machine without being torn, increasing cullage and lowering grade. Sweet cherries are brined in a solution of sulfur dioxide and lime rather than the usual salt-brine method used on other crops (4).
Abstract
Diesel exhaust was used for CO2 enrichment of vegetable crops in inflated plastic houses. Fuel source and components of the recovery system crucially affected the elimination of other harmful gases. The absence of an activated charcoal filter and the use of fuel high in sulfur content increased ethylene, sulfur dioxide, nitrogen dioxide, and probably others. In the gas-added environment, as compared with the ambient one, lettuce grew more slowly, and leaf size and yield decreased in cucumber and eggplant. Plants were exposed to the gas-added environment for about 5 months, after which the system was discontinued. Plants did not recover, and symptoms continued despite discontinuing gas addition.
An Air Quality Learning and Demonstration Center has been developed within the Arboretum at Penn State Univ.. The Center provides opportunities where students (of all ages) and teachers (grade-school through to classes within the Univ.) can learn about air quality as one of our most important natural resources. A seasonally interactive display of air quality monitoring instrumentation, self guided walkways through gardens of air pollution sensitive plant species, innovative techniques for demonstrating the effects of air pollutants on plants, displays of recent research findings, industry supported displays of pollution abatement technologies, and a teaching pavilion are within the Center. A Pennsylvania Dept. of Environmental Protection air quality monitoring station with ozone, sulfur dioxide, nitrogen oxides, carbon dioxide, PM < 2.5 u mass and speciation samplers, and a complete meteorological station provide data on the immediate environmental parameters. These data are relayed to an LCD crystal display board that has been mounted on the outside of the monitoring building; visitors are able to see the various measures of the air quality on a real time basis. Pannier type fiberglass display panels provide understandings of the various facets of air pollution formation and transport phenomena, air quality monitoring methods, the functions of open-top chambers, foliar symptoms expressed by pollution sensitive plants within the bioindicator gardens, and the impacts of pollution on agricultural and forested ecosystems. Handicapped accessible walkways lead visitors throughout the Center to the Teaching Pavilion that easily accommodates 80 persons. The pavilion is equipped with drop down curtains, electric power, and internet connections.
Abstract
Lettuce (Lactuca sativa L. cv. Grand Rapids) and radish (Raphanus sativus L. cv. Cherry Belle) plants growing at baseline environmental conditions were exposed to charcoal-filtered air, 0.40 ppm (v/v) ozone, and 0.80 ppm sulfur dioxide alone or in combination for 6 hours at 14 days from seeding. Analysis of covariance was used to account for significant within-treatment variation in plant growth. Covariates used were: planar leaf area (PLA) at 14 days for leaf area, fresh weight, and dry weight at harvest; plastochron index (PI) at 14 days for PI at harvest; and hypocotyl diameter for hypocotyl weights of radish roots at harvest. The covariates reduced the variability (standard geometric errors) of the response variables and increased the precision of statistical tests substantially for lettuce but much less for radish. For lettuce, the effect of the gas mixture on plant growth and foliar injury was less severe than that of the single gases. Radish plants, in contrast, exhibited no response to SO2 and the effects of O3 and the mixture on foliar injury and plant growth were similar.
fermentation was halted by reducing the temperature and clarified using 0.45-μm filters. Alcohol, density, and TA were measured and sulfur dioxide was added for sterilization. Finally, the cider was carbonated and bottled. The final cider was evaluated by four
. The amount of fruit processed ranged from 15 to 50 kg per cultivar. The grapes were stored overnight at 2 °C, removed from cold storage, crushed, and destemmed, and the must (juice, seeds, and skins) was placed in a food grade container. Sulfur dioxide
wet springs and warm and humid summers ( Hartman and Kaiser, 2008 ). Currently, synthetic fungicides applied in the field before harvest, and sulfur dioxide fumigations after harvest remain the common methods to fight gray mold on grapes ( Dean et al
postharvest organic program include controlled-atmosphere (CA) storage, sulfur dioxide, and ethylene gas ( Table 1 ). Chlorine, which is used extensively in conventional systems for washing produce, can be used for organic systems if the residual chlorine