Species and cultivars of Dieffenbachia Schott. (Araceae Juss.) have been important ornamental foliage plants for many decades. Their attractive foliar variegation, adaptability to interior environments, and ease of production are major reasons for their importance as ornamental foliage plants. Approximately 20 cultivars are commercially produced in Florida. Previously, most new cultivars were clones introduced from the wild or chance mutations of existing cultivars. Currently, cultivars are introduced into production from plant breeding programs (Henny 1995a, b; Henny and Chen, 2003; Henny et al., 1987). The hybrid Dieffenbachia `Sterling' was developed by the tropical foliage plant breeding program at the Mid-Florida Research and Education Center.
R. J. Henny, J. Chen, and D.J. Norman
R. J. Hutton
The Plant Patent Act of 1930 was a tremendous step forward in the development of new cultivars for ornamental horticulture and for the benefit of the American public. The `Peace' rose, PP 591, was the single breakthrough that had maximum impact. Prom the Plant Patent Act, other forms of breeders' rights were spawned worldwide, including our own Plant Variety Protection Act (PVPA). Proof of the success has been the increasing use and acceptance of plant patents and the lack of challenges to the act and plant patent litigation.
Christine E. Coker, Patricia R. Knight, and John M. Anderson
Sun coleus (Solenostenum scutellarioides) are commonly used in the southern landscape. However, with the introduction of new cultivars, producers and consumers may be unaware of the selection and landscape performance of sun coleus. Sun coleus cultivars were trialed under landscape conditions at the South Mississippi Branch Station in Poplarville, Miss., in 2000 and 2001. The objective of this study was to evaluate sun coleus cultivars based on landscape performance criteria including flowering, durability, vigor, uniqueness, and insect and disease resistance. Cultivars performing well over both years included `Ducksfoot Red,' `Ducksfoot Tricolor', `Ducksfoot Yellow', `Sunflower Red', `Pineapple', Mardi Gras', and `Saturn'.
A. A. Bee
Seeds from arborvitae, Thuja occidentalis L., cultivars were grown to determine phenotypic variations which might be useable as new cultivars. Seeds were germinated and grown under greenhouse and lath house condition. Many seedlings from isolated plants of T. occidentals `Hetz Midget' and `Holmstrup' were similar or identical to the parent plant (98% and 58%, respectively). Seedlings grown from seeds of plants in a mixed planting produced seedlings similar to the seed parent as follows: `Hetz Midget' 100%, `Minima' 78%, `Little Giant' 0%, `Sherwood Moss' 11%, `Spiralis' 24%, `Hoseri' 36%; cultivars that produce a high percentage of true to type seedling could be propagated sexually.
J. D. Norton, G. E. Boyhan, and B. R. Abrahams
Plum production in the Southeastern United States is limited because cultivars are susceptible to bacterial canker (Pseudomonas syringae), bacterial fruit and leaf spot (Xanthomonas pruni), black knot (Apisporina morbosa) and plum leaf scald (Xylella fastidiosa). Evaluation of four new cultivars developed by the Alabama Agricultural Experiment Station indicated that AU-Rubrum, AU-Rosa and AU -Cherry were resistant to all the diseases listed, and AU-Amber was resistant to all excapt A. morbosa. Disease ratings were made on trees in six experimental plantings in Alabama, in Georgia test plantings and in grower trials.
Gladiolus is one of the most popular flower crops grown in Romania. The breeding program at the University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca of this species has been especially focused on the improvement of main characteristics, such as color, number and form of florets, plant height, multiplication capacity, diseases resistance, etc. A program for genetic breeding of gladiolus varieties using different genitors (Romanian and foreign cultivars) was initiated. An intraspecific crossing between cultivars has been made followed by clonal selection and vegetative multiplication of the selections. In this paper, we show 15 new gladiolus selections, which were observed and analyzed in 2004–05. The selections obtained have a great uniformity of their morphological characteristics. These selections are more vigorous, producing greater number of florets with superior quality, have new colors of flower, and are distinguished by a long blooming time. The intraspecific variability of the above-mentioned characteristics was more than low, and rarely medium, high, or very high. These data suggest fair possibilities to choose the best selections that will be proposed for testing and homologation as new cultivars. The hybrids represent a step forward in combining high qualities in gladiolus. They will contribute to improving the assortment of gladiolus for cut flowers, landscape, or as genetic material, which can be used for new crossing in order to obtain new cultivars. Scientifically, a series of findings appeared considering the combining capacity of genitors, transmission of some useful qualities, and other aspects that contribute to improve of the new varieties.
Richard L. Fery, Blair Buckley, and Dyremple B. Marsh
The USDA, Louisiana State University, and Lincoln University have released a new southernpea cultivar named WhipperSnapper. The new cultivar is the product of a plant breeding effort to incorporate genes conditioning superior yield and seed characteristics of Asian vegetable cowpeas into American snap-type southernpeas. The new cultivar was developed for use by home gardeners and market gardeners as a dual-purpose cultivar that can be used to produce both fresh-shell peas and immature, fresh pods or snaps. Typical ready-to-harvest WhipperSnapper snaps are green colored, 6.4 mm in diameter, 7.6 mm in height, and 24 cm long; the pods are slightly curved at the attachment end. Typical mature-green pods suitable for fresh-shell harvest exhibit an attractive yellow color, are 25 cm long, and contain 14 peas. Fresh peas are cream-colored, kidney-shaped, and weigh 24.5 g/100 peas. Dry pods exhibit a light straw color, and the dry peas have a smooth seed coat. The quality of WhipperSnapper seed is excellent. In replicated field trials, WhipperSnapper produced significantly greater yields of both snaps and peas than the snap-type cultivar Bettersnap. WhipperSnapper has potential for use as a mechanically-harvested source of snaps for use by food processors in mixed packs of peas and snaps. Protection for WhipperSnapper is being sought under the Plant Variety Protection Act.
Richard L. Fery
The USDA–ARS has released a new pinkeye-type southernpea cultivar named GreenPack-DG. GreenPack-DG is the first pinkeye-type southernpea to be released that has a persistent green seed phenotype conditioned by both the green cotyledon gene (gc) and the green testa (gt) gene. The new cultivar was developed from a cross between Charleston Greenpack (green cotyledon phenotype) and the breeding line USVL 97-296 (green testa phenotype). Except for longer pods, GreenPack-DG is similar in appearance and maturity to Charleston Greenpack. Dry GreenPack-DG seeds have a richer and more-uniform green seed color than dry seeds of Charleston Greenpack. GreenPack-DG seeds are much less susceptible to color loss due to blanching when harvest is delayed than are seeds of green-cotyledon cultivars such as Charleston Greenpack. Color loss is a critical problem in production systems where preharvest desiccants are used to facilitate mechanical harvesting operations. The 7-day delay between application of the desiccant and initiation of harvesting operations can result in serious color degradation. Results of 3 years of replicated field tests at Charleston, S.C., indicate that GreenPack-DG yields are comparable to Charleston Greenpack yields. The new cultivar has excellent field resistance to blackeye cowpea mosaic virus and does not produce hard seeds. GreenPack-DG is recommended for trial by the frozen food industry as a replacement for Charleston Greenpack. Protection for GreenPack-DG is being sought under the Plant Variety Protection Act.
D. Scott NeSmith, Arlen D. Draper, and James M. Spiers
Released in 2004 by the University of Georgia and U.S. Dept. of Agriculture, `Vernon' is an early season rabbiteye blueberry (Vaccinium ashei Reade), having large fruit size, good yields and excellent plant vigor. `Vernon', tested as T-584, was selected in 1990 at the Coastal Plain Experiment Station in Tifton, Ga. from a cross of T-23 × T-260. `Vernon' fruit ripens early with the cultivar Climax in south Georgia, and few days before `Premier'; however, `Vernon' flowers 5 to 10 days after the standard cultivars. On average over a 6 year period, `Vernon' yielded 5.8 kg/plant per season, compared to 3.1 and 4.5 kg/plant for `Climax' and `Premier', respectively. Berry stem scar, color, firmness, and flavor of the new cultivar are good to excellent. Berry size of `Vernon' is considerably large, averaging 2.05 g/berry over 4 locations in 2003, compared to only an average weight of 1.56 g/berry for `Climax'. `Vernon' berries are firmer than `Premier'. Propagation of the new cultivar is easily accomplished from softwood cuttings. Chill hour requirement is estimated to be in the range of 500 to 550 hours (<7 °C). `Vernon' should be planted with other rabbiteye blueberry cultivars with a similar time of bloom to provide optimum pollination. Propagation rights are controlled by Georgia Seed Development Commission, 2420 S. Milledge Avenue, Athens, GA 30606 (for more information go to www.gsdc.com).
Henry M. Donselman
Tissue culture labs based in countries with high labor costs are becoming more dependent on proprietary plants. This has increased the necessity of high profile plant breeding programs. Foliage and flowering plant breeding programs have evolved rapidly to take advantage of the benefits associated with tissue culture labs.
Breeding strategies and methods will be discussed on existing flowering and foliage programs for Anthuriums, Euphorbia, Aloe, Spathiphyllum, Homalomena, and Dieffenbachia. Embryo rescue in the lab has increased the survival of wide crosses from different species within a genera. Rapid multiplication of selected clones has increased the efficiency of screening for disease and insect resistance in the selection of new cultivars. Marketing, along with improved horticultural characteristics, determine the success of new releases.