coordinating activities to aid expansion of the industry. The most consistent limitation to industry expansion has been freeze stress. More recently, however, warmer water temperatures in the Atlantic and Gulf of Mexico have fueled hurricanes that cause wind
A daminozide plus chlormequat chloride tank mix spray was applied to six Coleus cultivars or breeding lines at different times during propagation. For UF 03-8-10 and `Coco Loco', plants sprayed on day 7 or day 10 were shorter than control plants at transplant, but plants sprayed on day 13 were not. Other cultivars did not respond to single applications. Five of the six cultivars responded to application on days 7 and 13. Plants of UF 03-8-3 and `Coco Loco' were significantly shorter than control plants at transplant. Plants of UF 03-8-10, UF 03-6-1, and UF 03-17-8 were shorter than control plants at 3 weeks after transplant. `Hurricane Louise' did not respond to the tank mix. A second study found a cultivar specific response to three chemical treatments applied as a spray on day 10 of propagation. At transplant, UF 03-8-10, UF 03-8-3, UF 03-6-1, and `Coco Loco' plants sprayed with the tank mix at 2500 plus 1500 mg·L-1, respectively, were significantly shorter than the control plants. A uniconazole spray at 2 mg·L-1 reduced elongation in UF 03-8-10, UF 03-8-3, and UF 03-6-1, compared to control plants. Ethephon at 250 mg·L-1 reduced elongation in UF 03-8-10, UF 03-8-3, and `Coco Loco' plants. None of the chemical sprays reduced elongation in `Hurricane Louise' at the concentrations applied. Ethephon increased axillary branching in all cultivars, and induced lower leaf abscission in UF 03-17-8 and `Hurricane Louise'; leaf malformation in UF 03-6-1 and `Coco Loco'; and color alteration in UF 03-6-1, UF 03-8-3, and `Coco Loco'.
Three hurricanes in Florida starting in late Summer 2004 caused severe leaf loss, which stimulated many fall shoots. Flush occurred after each hurricane and by December, shoots were 6- to 12-weeks-old when cool temperatures capable of causing flower bud induction started. To evaluate the potential for these flushes to mature buds that could be induced to flower, flushes that were stimulated on potted trees in a greenhouse were allowed to mature 4, 6, 8, or 10 weeks before moving trees to flower-inducing conditions for 6 weeks (15 °C day/10 °C night). Plants were then returned to the greenhouse, which was kept at 20 °C or higher (ambient), until buds sprouted. Only 1% of sprouting buds on shoots that matured for 4 weeks had flowers. In shoots that matured for 6 weeks, 18% of sprouting buds had flowers. After 8 weeks of growth, 57% of the buds that sprouted were flower buds, while after allowing 10 weeks for shoots to mature, induction resulted in 76% of the sprouting buds producing flowers. Consequently, 8 weeks of development were necessary for citrus shoots to develop mostly mature buds that responded to flower inductive conditions. This is about the same amount of time required for new citrus leaves to fully mature.
Trees were pruned by removing 1, 2, or 3 leader limbs per year or not pruned from 1975 through 1993. Cuts were made flush with another limb below 9 m from the ground. Pruning induced trees to respond like younger trees. Pruning increased leaf N, P, Mg, Mn, Fe, Zn, vigor, color intensity, terminal growth, nut size, and nuts per terminal. Kernel grade was reduced slightly by pruning. Yield was reduced by two or three pruning cuts per year, but not by one cut. Pruned trees were lower, more spreading, and more efficient to spray. Removal of one leader per year satisfactorily held the tree within the 21.3 × 21.3 m spacing without reducing yield. The lower height of pruned trees should decrease loss from high winds. All pruned trees survived a hurricane and a small tornado, while many unpruned trees in the area were blown down.
The 199 sweetpotato growing season was one of extremes: early high temperatures, cool temperatures at planting, drought early and extended, and then hurricane floods. Insect species and population levels were highly variable. Thrips early and armyworms late. Insect control tactics and management strategies were used and include the following. Insect presentations and handouts were made at field days, annual meeting and at several county meetings. A sweetpotato insect field guide was prepared to assist fieldmen with insect scouting. Insect scouting schools were held in several counties to show insects, their damage, and traps to use in detecting their presence and numbers over time. Control studies with insecticide formulations and rates along with timing studies were conducted and prepared for the annual report. Spintor and Admire received registations for worms late and for early season insect control. Aphid vector studies centered on aphid suction traps, yellow sticky traps, and aphid identifications. Foliar and soil insecticides were discussed as to their use and impact. Insecticides of the future were presented and discussed. Cooperative studies and long term plans were discussed.
Working on the basic idea that the small fruit industries in Virginia, South Carolina, Georgia, Arkansas, and other states in the south have a great deal of growth potential, especially in strawberries, the Southern Region Small Fruit Center is now becoming a very focused collaboration between several land-grant institutions to develop a virtual small fruit center web site that will serve to keep specialists, agents, growers, and students well informed on the latest small fruit research and technical findings. It would also give instant access to a variety of small fruit extension publications, budgets, and crop advisories. The site, www.smallfruits.org, opened on 17 Sept. 1999, and was immediately utilized after Hurricane Floyd “hit” to post a series of berry info advisories on specific postplant management strategies to minimize further yield losses due to the extra week of delayed planting caused by Floyd's flooding. The main benefit of regional or multistate institutional approach is that it gives us the “extra horsepower” for tackling some fairly ambitious projects, like the creation of a virtual small fruit center. Recently, the center has begun to offer more in-depth regional training courses for agents and growers, such as the “Extension Strawberry Plasticulture” short course that was conducted on North Carolina State Centennial Campus, 1-5 Nov. 1999. We currently have a “critical mass” of some of the best small fruit research and extension workers you will find anywhere across the whole southern region, and by working together we can develop stronger, more economically viable small fruit industries.
Florida tomato growers have been managing tomato mottle mosaic virus (TMoV), vectored by the silverleaf whitefly (Bemesia argentifolia) since 1990. Bean growers in the Dade and Palm Beach County area have tried to control bean golden mosaic virus (BGMV) since it entered the area with Hurricane Andrew in 1992. During Summer 1997, tomato yellow leaf curl virus (TYLCV) was found in summer-grown tomatoes in Dade County. In Fall 1997, tomato growers were notified of the new problem and attended a workshop discussing the rigorous control that would be needed to minimize its effects. They instituted scouting and roguing programs in conjunction with appropriate pest management procedures. Dade bean growers worked with the Florida Fruit & Vegetable Assn. to obtain a Section 18 for imidacloprid. Bean and tomato growers learned about gemini viruses affecting both crops and the distribution of these viruses in the Americas in the fall of 1998. Bean growers have also learned how to use imidacloprid in late 1998/early 1999. Extension methods used and their success will also be discussed.
The Production of the cut flowers of Anthurium andreanum was in decline after Hurricane Gilbert in 1988 and the subsequent wide-spread problem of bacterial blight in Jamaica and the Caribbean. New methods of cultivation and new varieties were necessary for the development of the industry. In addition, with the destruction of coconut trees, the supply of commonly used coconut husk became difficult. The present work has focused on the development of alternative media to coconut husk and on the development of cultural and fertilizer practices that increase plant productivity and reduce incidence of disease. The variety Honduras was chosen for the study. A 3 × 3 latin square design was used to evaluate four media—coconut husk, brick chips, gravel, and basalt igneous rock—two methods of cultivation—pots and beds; at three levels of fertilizer—244, 448 and 896 kg N/ha per year. While the coconut husk was still the better medium, the other media have resulted only in about 15% decline in the marketable blooms. This was offset by the requirement for low maintenance and lower fertilizer rates in inorganic media compared to coconut husk. Pot culture proved to be better for management purposes as well as production for the same area of production, as density of the plants could be increased and the incidence of disease could be easily managed. These results will be discussed with emphasis on a simple cost–benefit analysis of various combinations of cultivation methods and practices for commercial cultivation of A. andreanum var. Honduras in the Caribbean.
Yellow and zucchini squash (Cucurbita pepo L.) cultivars/elite lines (cultigens) were evaluated over two seasons (fall 1995 and spring 1996) in North Carolina. Different cultigens were tested over the 2-year period for both yellow and zucchini squash, although some cultigens were tested both years. Cultigen recommendations are based on yield, quality, disease resistance, and season grown. Yellow squash cultigens that yielded well include: Destiny III, Freedom III, Multipik, TW 941141, Liberator III (fall 1995); and HMX 4716, Superpik, PSX 391, Monet, Dixie, Picasso, and XPH 1780 (spring 1996). Superior-yielding zucchini squash cultigens were: TW 940981, Tigress, TW 940982, ZS 19, Elite, and Noblesse (fall 1995); and Leonardo, Hurricane, Elite, HMX 4715, Noblesse, and Tigress (spring 1996). Virus ratings for fall 1995 indicated that some transgenic plants with virus resistance withstood virus infection better than those without resistance. These were Freedom III, Destiny III, Freedom II, Liberator III, Prelude II, and TW 941121 (yellow), and Tigress, TW 940982, TW 940981, TW 940866 (zucchini). Virus-infected plants were assayed and viruses were determined to be zucchini yellow mosaic, watermelon mosaic II, and papaya ringspot.
A study was conducted in 2004 comparing commercial plant restraint systems with a grower standard consisting of a steel rod driven through the container into the soil. Commercial systems included wire baskets, aboveground plastic pot-in-pot, trellis with straps, and brackets on individual posts. This test was conducted on 15-gallon containers. Costs and efficacy of the systems were recorded. All of the commercial systems worked well, but the annualized cost of the grower standard was much less even though more blow-over occurred with the grower standard. A different system consisting of a horizontal rod over the top of containers and held down with J-stakes was tested on 4-gallon containers. Not enough stakes were used and the system was less effective than vertical stakes in each pot. A new study was initiated in 2005 to refine the grower standard through the use of one or two stakes per container, longer stakes, and the use of rebar instead of smooth rod. More stakes, longer stakes, and rebar were also evaluated with the horizontal rod system. The 2005 test was lost due to Hurricane Katrina. It will be repeated in 2006.