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  • Author or Editor: J. L. Morris x
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Abstract

Several Arkansas commercial grape growers operating tractor-mounted, low-boom vineyard spray rigs were monitored for potential dermal, respiratory, and internal exposure to paraquat (1-1′-dimethyl-4,4′-bipyridinium ion) during the 1980 and 1981 growing seasons. Workers followed their usual mixing and spraying routines with as little influence as possible from the test. Analyses by colorimetric methods revealed very low levels of paraquat exposure. Greatest dermal exposure levels averaging 0.015 mg paraquat/kg body weight were detected on persons operating the spray rigs. Respiratory exposure was minimal and there was no paraquat detected in any of the urine samples collected from each worker. Those persons receiving the highest levels of paraquat exposure had measurements which were well below those found to be toxic to laboratory animals. Hazards from using this material by this method of application should be low when used in accordance to label directions and precautions.

Open Access

Abstract

Four of 7 strawberry (Fragaria X ananassa Duch.) clones tested did not benefit in total yield from 1 or 2 hand pickings prior to once-over machine harvest. Four of the clones could be hand picked once without a significant reduction in machine harvested yields. Two clones were low yielding regardless of the harvest method. ‘Sunrise’, a high once-over yielding clone, increased in total yield with hand harvesting but fruit were soft and poorly colored and lacked good field holding and in-plant handling capabilities. ‘Cardinal’ represented a clone with fruit quality and a ripening pattern suitable to a combination of hand and machine harvesting. Fruit remaining on the plants after 1 or 2 hand harvests had a higher percentage of ripe fruit in the once-over harvest than machine harvested fruit not preceded by a hand harvest. The composite once-over machine harvested fruit after 1 or 2 hand pickings showed the same or higher soluble solids, shear press firmness, puree viscosity and color intensity as hand harvested fruit. In clones with high quality fruit, the presence of immature fruit in the onceover harvest did not detract from puree color or flavor acceptability. Selection A-5344 possessed both yield and quality characteristics desired for a completely mechanized harvest for processing.

Open Access

Abstract

The response of an Arkansas breeding-line 5344 of strawberry (Fragaria X ananassa Duch.) to 0, 1 or 2 hand pickings prior to once-over machine harvest and to the timing of the machine harvest was examined for 3 years on the same planting. Increased yields from 1 or 2 hand pickings prior to machine harvest were lost by delaying machine harvest past the estimated optimum time (80 to 85% ripe fruit). Machine-harvested yield was reduced by hand picking and/or by delaying the time of machine harvest past the optimum period. Machine- harvested fruit quality was reduced in % soluble solids, acidity and color compared to the quality of hand-picked fruit but tended to improve as the number of hand pickings prior to machine harvest increased. Organoleptic evaluations of fruit puree from all harvesting treatments were rated acceptable.

Open Access

Abstract

Fruit samples of grape (Vitis labrusca L., cv. Concord) from 6 vineyard locations were collected at 7 to 10-day intervals beginning prior to veraison and continuing through development of 16% soluble solids for a period of 19 years. The 19-year average date for peak bloom in these vineyards was May 19, for 8% soluble solids development was July 27 (69 days from peak bloom), and for 16% soluble solids development was August 23 (96 days from peak bloom). Heat unit summations were more closely related to development of soluble solids than to changes in either titratable acidity or color. Using degree-day accumulations and effective heat unit summations did not prove to be methods superior to use of the number of calendar days for predicting grape maturation. Predictions from 8 to 16% soluble solids development were more accurate than predicting from peak bloom (when 50% of clusters showed bloom). Variations between years and between vineyard locations within a given year prevented accurate predictions from the 3 methods. Other deterrents observed in predicting development of soluble solids included the cultural variables of fruit load and soil moisture.

Open Access

In the United States, urban population growth, improved living standards, limited development of new water supplies, and dwindling current water supplies are causing the demand for treated municipal water to exceed the supply. Although water used to irrigate the residential urban landscape will vary according to factors such as landscape type, management practices, and region, landscape irrigation can vary from 40% to 70% of household use of water. So, the efficient use of irrigation water in urban landscapes must be the primary focus of water conservation. In addition, plants in a typical residential landscape often are given more water than is required to maintain ecosystem services such as carbon regulation, climate control, and preservation of aesthetic appearance. This implies that improvements in the efficiency of landscape irrigation will yield significant water savings. Urban areas across the United States face different water supply and demand issues and a range of factors will affect how water is used in the urban landscape. The purpose of this review is to summarize how irrigation and water application technologies; landscape design and management strategies; the relationship among people, plants, and the urban landscape; the reuse of water resources; economic and noneconomic incentives; and policy and ordinances impact the efficient use of water in the urban landscape.

Free access