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  • Author or Editor: Clarence Johnson x
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Asparagus (Asparagus officinalis)plants were sprayed and drenched with different concentrations of Promalin (0, 250, and 500 ppm) The varieties for the spraying experiment were `Mary Washington', `Emeral', `UC-157-F1', and `UC157F2'. Six replications for each treatment were used in a randomized complete-block design. The drenching experiment used two varieties (Mary Washington and UC-157-F2) with six replications of each treatment in a randomized complete-block design. Pots were numbered and labeled for each experimental unit. Plants (ferns) were counted and recorded in order to obtain the initial number of ferns before or after the spraying or drenching. In the spraying experiment, the plants were sprayed to run-off using a hand sprayer whereas; in the drenching experiment, 1000 mL or 1 L of the solution was used to drench each plant. The response to the chemical was measured in two ways: weekly stimulation of emergence of new-shoots and percent increase in final number of shoots over the initial number. In the spraying treatments differences were not found among the treatments used. In the drenching experiment with `Mary Washington' variety, a lower initial number of ferns at 250 ppm as compared to the 0 ppm of Promalin (8.82 to13.00) was observed. Differences for `Mary Washington' variety was not found for cumulative number of ferns on weeks 1, 2, and 3. However, the percent increase in number of ferns was higher for the 250 ppm as compared to the 0 ppm (174.55% to 78.14%). `UC-157-F2' showed no difference among the different concentrations. This indicates a difference in varietal response.

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Spraying 9-month-old UC157F1 asparagus plants (Asparagus officinalis L.) with aqueous solutions of GA4/7, BA, and promalin ranging from 0 to 200 ppm in 200-ppm increments and using the mother-stalk method showed that BA continued to produce the most marketable shoots and obtained a higher level of effectveness. GA4/7 showed significance on several days during the harvest period. On the final day, there was no significant difference found for either GA4/7 or promalin. BA produced marketable shoots earlier than promalin, but in the end, both these chemicals were equally effective. Early interaction with GA4/7 × BA resulted in delayed shoot emergence. Promalin is a mixture of GA4/7 and BA.

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During Fall 2003, a study similar to that of Fall 2002 was conducted to determine the effect of crown manipulation on shoot production in four cultivars of daylily. Three crown manipulation treatments: (1) the shoot cut back two centimeters from crown, (2) the shoot cut back to the crown, and (3) shoot cut back to the crown and scooped out were compared to a control. Four daylily cultivars, `Bull Durham', `Amber Lamp', `Angus McLeod', and `Alvatine Taylor' were used in this study. After eight weeks of observations, the results showed that the cut back to crown treatment caused a significant increase in the number of shoots when compared to the control and other two treatments. Shoot production for the cultivar `Angus McLeod' was significantly better than the other cultivars. Results obtained for Fall 2003 study were similar to that of Fall 2002. These results imply that cutting the shoots back to the crown in some daylily cultivars could possibly be used to enhance multiplication of daylilies during propagation.

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Abstract

Field studies conducted during the summers of 1983 and 1984 evaluated the influence of different types of mulching materials on growth and development of ‘Black Beauty’ eggplant (Solanum melongena L.). Treatments consisted of a) pine needles, b) newspaper, c) black plastic, and d) no mulch. The effects of mulching on earliness, growth index, soil moisture, temperature, pH, leaf nutrient content, weed control, and yield were measured. In 1983, a year of limited rainfall, all of the mulching treatments caused a significant increase in growth when compared to the unmulched treatment. Growth was unaffected by mulching in 1984, a year of abundant rainfall. Earliness, measured by the number of fruit per plant prior to the first harvest, was significantly increased by black plastic in 1983 but was not affected in 1984, which suggests the effectiveness of mulching under limited rainfall. In both years, mulching did not affect soil pH, leaf nutrient content, or soil temperature. Black plastic or pine needles were significantly more effective than newspaper in conserving moisture and controlling weeds. Black plastic increased yields significantly compared to the unmulched control in 1983, whereas black plastic or pine needles increased yields in 1984.

Open Access

One-year-old greenhouse-grown `Mary Washington', `Emerald', `UC 157 F,', and `UC 157 F,' asparagus (Asparagus officinalis L.) seedlings were sprayed on 23 Sept. 1988 with dikegulac concentrations ranging from O to 750 mg·liter-1 in 150-mg·liter-1 increments. No significant shoot emergence occurred before frost killed the ferns in December. With increasing temperature in Jan. and Feb. 1989, dikegulac promoted shoot emergence in all cultivars, except `Mary Washington'. At 600 mg·liter-1 dikegulac had increased shoot emergence in `Emerald', `UC 157 F,', and `UC 157 F2' by 310%, 161%, and 305%, respectively, over the control on 2 Feb. After frosts killed the first shoots, all cultivars responded to treatment as temperature increased. Dikegulac did not affect the height and dry weight of `Mary Washington' ferns, but it reduced the height of `Emerald' without affecting its dry weight. Both height and dry weight of `UC 1571 F' and `UC 157 F2' were reduced by the chemical. There was a significant effect of cultivar on shoot production regardless of treatment, but no significant cultivar × dikegulac interaction on shoot emergence. However, there were significant effects of cultivar and cultivar × dikegulac interaction on height and dry weight of the ferns. After the ferns had been cut off on 9 Aug. 1989, only `UC 157 F1' and `UC 157 F2' showed increased shoot emergence. A second treatment of the plants with the chemical on 23 Sept. 1989 resulted in no significant increase in shoot emergence before or after freezing temperatures killed the ferns. Chemical name used: 2,3:4,6-bis-0-(l-methyl ethylidene)-a-L-xylo-2 -hexulofuranosonic acid (dikegulac).

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Mary Washington, UC157F1, and UC157F2 asparagus cultivars were grown from 1-year-old crown under greenhouse conditions in 30-liter pots containing Pro-Mix medium. The roots were cut to 10 cm prior to planting on 12 Feb. 1991. On July 12, 1991 the plants were transferred outdoors and sprayed with BA, GA4/7 and Promalin at 400 mg. liter-1 using tap water as control. On July 16, 1991 the treated ferns were cut at ground level and the plants were returned to the greenhouse, and arranged in a RCB design. Seven reps with one pot/rep were used. Data on time of emergence of first shoots were recorded daily until all pots had produced at least 1 shoot. When all plants had sprouted, cumulative number of all shoots/pots was recorded weekly thereafter over 5 weeks. BA and Promalin reduced time of emergence of shoots and increased the number of shoots/plant. GA4/7 had no effect on shoot emergence or shoot number.

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During the summer of 1988, a study was conducted to determine the effect of an inexpensive reusable styrofoam container on the percent weight loss in collards (bunch and head) after 30 days in a walk-in cooler. This container was designed and constructed for precooling, shipping, and storing fruits and vegetables. The insulated container was provided with a lid-mounted ice cavity that was removable and could be replaced through an access door without removing the lid. The ice cavity melted and was dispersed throughout the container onto the collards. The three treatments used in this study were (1) no top (2) top without ice, and (3) top with ice. Results indicated that both the bunches and heads responded similarly to treatments. The top with ice treatment significantly reduced percent weight loss when compared to the other treatments (top no ice and no top).

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On Sept. 23, 1988, 12-month-old greenhouse-grown `Mary Washington', `Emerald', `UC 157 F1' and `UC 157 F2' asparagus seedlings were sprayed with dikegulac solutions ranging from 0 to 750 mg·l-1 with 150 mg·l-1 increments. The potted plants were then transferred to a lathhouse to simulate the weather conditions in the field. No significant shoot emergence occurred prior to killing frosts and low temperatures in December. The rise of the temperature in Jan. and Feb. 1989, promoted shoot emergence in all cultivars; but `Mary Washington' did not respond to the treatments. At 600 mg·l-1, the chemical increased shoot emergence in `Emerald', `UC 157 F1' and `UC 157 F2' by a respective cumulative average of 310, 161 and 305% over the control on 2 Feb. After intervening killing frosts and low temp, at the resumption of growth in late February 1989, `UC 157 F,' and `Mary Washington' were first to respond to the residual effects of the chemical, giving at 750 mg·l-1 a respective cumulative increase of 65 and 77% over the control. Dikegulac did not affect the height and dry weight of `Mary Washington' ferns. But it reduced the height of `Emerald' without affecting its dry weight.

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Abstract

Spraying 9-month-old asparagus seedlings (Asparagus officinalis L.) with dikegulac-sodium (atrinal) solutions ranging from 0 to 500 ppm in 100-ppm increments increased the number of new shoots, particularly within the range of 300 to 500 ppm. The response was elicited 4 weeks after the treatment and continued thereafter over the 10 weeks, during which measurements were taken. Dikegulac did not affect the height or the fresh and dry weights of the plants for this first phase. Emergence of new shoots after the plants had been cut off was equally affected by dikegulac; 300 to 500 ppm was still the most effective. However, effectiveness was significant after 2 weeks. The height of plants was significantly reduced by the chemical, but the fresh and dry weights were not affected. At the third phase, none of the growth characteristics, including shoot emergence, was affected by the chemical. This lack of response may be attributable to the depletion of carbohydrate reserves in the fleshy roots. Chemical name used: 2,3:4,6-bis-O-(1-methylethylidene)-α-L-xylo-2-hexulofuranosonic acid (dikegulac).

Open Access