Flowering of Macadamia integrifolia trees was monitored following application of 220 mg/liter gibberellic acid (GA3) at various times preceding the onset of the flowering season. In untreated trees, flowering extended over a 4-5 month period. When GA3 was applied at 2, 3 and 4 months before the onset of anthesis, raceme production during the entire flowering season was inhibited. A slight reduction in raceme production was observed when GA3 was applied at 1 month preceding anthesis. This application coincided with appearance of the earliest infloresceuces. GA3 application after the onset of anthesis did not alter the flowering pattern of trees during the remaining 4 months of the flowering season. Results suggest that GA3 inhibits flower initiation, but has no effect on raceme emergence after flower bud differentiation has occurred. The relationship between flower initiation and raceme emergence will be discussed.
Mike A. Nagao, Elodie B. Ho-a, and Judy M. Yoshimoto
S. Severmutlu, N. Mutlu, R.C. Shearman, E. Gurbuz, O. Gulsen, M. Hocagil, O. Karaguzel, T. Heng-Moss, T.P. Riordan, and R.E. Gaussoin
Traditionally cool-season turfgrasses such as perennial ryegrass ( Lolium perenne ), tall fescue, and kentucky bluegrass ( Poa pratensis ) are the dominant species used as turf in the Mediterranean region of Turkey and in similar regions of
Timothy M. Spann*, Robert H. Beede, Steven A. Weinbaum, and Theodore M. DeJong
Rootstock significantly alters the pattern of shoot growth of pistachio (Pistacia vera) cv. Kerman. Trees on P. atlantica typically produce a single flush of spring growth whereas trees on P. integerrima selection PGI and P. atlantica × P. integerrima selection UCB-1 can produce multiple flushes during the season. Terminal buds of shoots on all three rootstocks were dissected during the dormant season to determine the number of preformed nodes. Data indicate that there are 8-9 nodes preformed in the dormant terminal bud of shoots from Kerman trees and that this number is independent of rootstock, canopy location, crop load, and shoot carbohydrate concentration, suggesting genetic control. This number corresponds with the number of nodes typically found on a shoot at the end of the spring growth flush. Unlike the spring flush which is preformed in the dormant bud, later flushes are neoformed, that is, nodes are initiated and extended during the same season. Neoformed growth depends on current season photosynthates and may compete with fruit growth for available resources. Neoformed growth is sensitive to water stress and trees on all three rootstocks grown under two levels of regulated deficit irrigation showed a reduction in both the number and length of neoformed shoots. Preformed shoot growth did not appear to be reduced under water stress conditions, supporting the hypothesis that preformed shoots are more dependent on environmental conditions during the season they are initiated than during the season they are extended. Additionally, preformed shoots on well irrigated trees were similar in length for all rootstocks, further supporting the idea that preformed shoots are under genetic control and are not easily manipulated.
William James Lamont Jr.
Plasticulture, simply defined, is a system of growing crops wherein a significant benefit is derived from using products derived from plastic polymers. The discovery and development of the polythylene polymer in the late 1930s, and its subsequent introduction in the early 1950s in the form of plastic films, mulches, and drip-irrigation tubing and tape, revolutionized the commercial production of selected vegetable crops and gave rise to plasticulture. The later discovery of other polymers, such as polyvinyl chloride, polyproplene, and polyesters, and their use in pipes, fertigation equipment, filters, fittings and connectors, and row covers further extended the use of plastic components in this production system. The plasticulture system consists of plastic and nonplastic components: plastic mulches, drip irrigation, fertigation/chemigation, fumigation and solarization, windbreaks, stand establishment technology, season-extending technology, pest management, cropping strategies, and marketing.
Gerry Neilsen, Denise Neilsen, Shufu Dong, Peter Toivonen, and Frank Peryea
Calcium application trials were undertaken in a 'Braeburn' apple (Malus ×domestica Borkh.) orchard with a history of bitter pit development at harvest. In 2000, an early season calcium chloride application strategy was compared with the unsprayed control and a late season application strategy. From 2001–03, the assessment of timing of calcium chloride sprays was extended by comparing effects of five weekly sprays applied during the growing season either early, middle, or late season. Other Ca application strategies tested included sprays of acidified calcium carbonate suspensions and soil application of calcium thiosulphate. In the first experiment, early application of calcium chloride reduced the occurrence of bitter pit at harvest and after 3 months cold air storage, despite having low harvest fruit Ca concentrations. Late sprayed fruit had a higher incidence of bitter pit. In the second experiment, the later calcium chloride was sprayed in the growing season, the higher the fruit Ca concentration at harvest. Despite this, no bitter pit was measured at harvest for 2 years for early and midseason calcium chloride spray regimes. In 2003, when Ca disorders were severe and fruit large, bitter pit was observed despite early season calcium chloride sprays. Soil calcium thiosulphate application and foliar sprays of acidified calcium carbonate suspensions failed to meaningfully augment harvest fruit Ca concentrations and affect bitter pit incidence.
Owen M. Rogers
Current lilac breeding programs at the University of New Hampshire focus on the later (June) blooming species of Syringa with goals of extending the season of bloom selecting slower growing forms and developing lines with double flowers. Progress toward these goals and others, e.g., true dwarfs, will be discussed and illustrated.
Every university in the northeast includes woody ornamentals in its program to some degree. The University of New Hampshire is an official test site for ornamental from NE-9 and NC-7 germplasm programs and the National Arboretum's new introduction program. The value of these programs and their future direction will be discussed.
R.B. Beverly, Sonni George, and G.O. Gaye
Vegetable gardening in The Gambia provides an important supplemental income for women farmers who grow tomato, onion, cabbage and other vegetables for sale on the local market, to restaurants and for export to Europe. Government and international agencies provide research and technical support, while non-governmental organizations (NGO's) provide production capital (such as wells) and marketing support. Production problems include pest management and the labor intensity of hand irrigation and harvesting. Growers cite low prices as their greatest constraint. Small local canning facilities may help alleviate market gluts and extend marketing and consumption opportunities beyond the fresh market production season.
Serge Bégin, Joe Calandriello, and Pierre A. Dubé
In Québec the intensive use of plastic films in field production of vegetables and fruit is evident by increased acreage for this sector of agriculture since 1985. This technique is used particularly for sweet corn, cucurbitaceae and solanaceae, and strawberry production. Since 1987 some research projects have been established by the research and development division of the Quebec ministry of agriculture (MAPAQ) to adapt this technology to the Québec climate and to the needs of producers. The objectives of MAPAQ researchers are to extend the production season, improve the quality and productivity of fruit and vegetable crops, diminish production costs, and propose profitable alternatives for controlling crop pests.
R.C. Shearman, L.A. Wit, S. Severmutlu, H. Budak, and R.E. Gaussoin
Dormant buffalograss (Buchloë dactyloides) turfs, grown under field conditions, were treated with a colorant and evaluated for turfgrass color, quality, and cover. In addition, turfgrass canopy and soil temperatures were measured. Colorant treatments improved turfgrass color and quality when compared to the untreated control, and resulted in a color response that appeared similar to cool season turfgrasses growing in areas adjacent to the studies. Colorant treatments increased canopy and soil temperatures, and enhanced spring green-up. These results support the use of colorants as a means of extending the green appearance, and enhancing dormant buffalograss turf performance.
Karen L.B. Gast and Melinda McMillan
Peony flowers are among the few fresh-cut flowers that can be stored dry at cold temperatures for weeks and still produce a viable product for the marketplace. Devising new ways to extend that storage period could open new markets for peony growers. In the northern hemisphere, more peonies could be available for summer weddings, and in the southern hemisphere, red peonies could be used for Valentine's Day. Being able to control and extend the vaselife of peony flowers could also be useful for companies that freeze-dry peonies. Their production is limited by the length of their processing cycle and the size of their freeze dryer. Being able to extend their production season could make them more profitable. Three treatments were applied to peony flowers harvested in the colored bud stage before flowers where placed in cold storage, 2°C. An untreated control was included. Flowers were removed from storage every 2 weeks for 14 weeks. Vaselife and fresh weights were evaluated. Total nonstructural carbohydrate levels of the petals, leaves, and stems of the flowers are to be analyzed. Preliminary analysis of the data shows some treatment differences.