Abstract
Hybrid lisianthus [Eustoma grandiflora (Raf.) Shinn.] was evaluated as cut flower and flowering pot plants. Lisianthus is a day neutral summer blooming plant blooming earlier at high growing temperatures (18°/26°C night/day) than at low temperatures. It is a slow growing plant, requiring about 5 to 6 months from sowing to flowering. Forcing period is about 2 months. Three color variants are available: blue, pink, and white. Only the blue and white are suitable as cut flowers. About 3 cut flower stems are produced per plant in the 1st harvesting cycle, and retaining the plant for a 2nd crop is considered uneconomical. Keeping quality of the cut flowers can be improved by pulsing for 24 hr with a solution containing 5% to 10% sugar, and desirable blue and pink pot plants were obtained by spraying with butanedioic mono-2.2-dimethylhydrazide (daminozide, B-Nine). The white cultivar did not respond to daminozide but did respond to soil application of a-cyclopropyl-a-(p-methyoxyphenyl)-5-pyrimedine methyl (ancymidol). Flowering pot plants should be grown in the greenhouse until about half of the flower buds on the plants open, since buds do not develop properly under home conditions.
More than three dozen species of Heliconia have entered the cut flower trade since the expanded interest in bold tropical cut flowers began in the early 1980s. Most were wild-collected originally with little information on their habitats or season of bloom. A natural flowering season for some species can be found in the taxonomic literature, but it may be influenced locally by rainfall and drought periods as well as by photoperiod and therefore not reliable in indicating production periods in Hawaii. Sales records from 1984 through 1990 or several heliconia growers on Oahu reflected not only the quantities produced but also the time and duration of the blooming season. Such information is helpful in coordinating with the flower markets. Heliconia species of commercial interest with strong seasonal flowering periods are noted: angusta, bihai, caribaea, caribaea X bihai, collinsiana, farinosa, lingulata, rostrata, sampaioana, stricta, subulata, wagneriana.
Eighteen New Guinea impatiens cultivars were evaluated for performance as bedding plants and for suitability as hanging basket plants. The cultivars were treated with three growth retarding chemicals (B-9, Sumagic and Cutless) to determine their effect on plant growth, branching and overall flower development. Two applications of 2500 ppm B-9 produced the most commercially acceptable plants. Height and spread were reduced by approximately 30 percent with no reduction in the number of flowers produced or the number of days to bloom. Cutless and Sumagic applications reduced growth approximately 50 percent and delayed blooming as much as 2 weeks when compared to the untreated control. Growth regulator treatment had no effect on the number of branches produced except with Sumagic which resulted in an overall reduction in branching.
Interspecific hybridizations among members of the genus Hamamelis (the witchhazels) and Corylopsis were carried out in 1993, 1994, 1995, and 1996 at the U.S. National Arboretum. Specifically, crosses involving the native witchhazel (H. vernalis and H. virginiana) and the Asian taxa (H. mollis, H. japonica, and H. × intermedia) were attempted in order to combine the ornamental qualities of the Asian species with the adaptability and fall blooming characteristics of the native species. Additionally, C. platypetala, a hardy species with small inflorescences, was crossed with C. himalaica, which has large showy inflorescences but is less hardy. Approximately 50 seedlings resulting from these crosses have been analyzed using randomly amplified polymorphic DNA (RAPD) markers to verify interspecific hybridization. Based on these assays, we report the first incidence of controlled interspecific hybridization between the Asian and native witchhazel taxa.
The proportion of spurs blooming on `McIntosh' apples (Malus domestica Borkh.) was reduced significantly in 1986 and 1988, but not in 1987, following seasonal programs of six bitertanol or flusilazole treatments applied at two and three rates, respectively. The fungicides were not associated with any visible phytotoxic effect nor was shoot length reduced by any fungicide treatment. In two of three experiments conducted in May and June 1986, transpiration was reduced by the low rate of flusilazole and the high rate of bitertanol relative to both the captan and nonsprayed trees. In all three experiments, flusilazole at 1.4 g a.i./100 liter was associated with transiently reduced transpiration rates, lasting a minimum of 48 hours, relative to the nonsprayed control. Fungicides affected the diffusive resistance of apple leaves in all three experiments; however, there were no consistent treatment effects on diffusive resistance among the three experiments.
Cleistogamy in Salpiglossis sinuatu L. involves a sequence of events, including arrested corolla development, precocious pollen germination inside anther, pollen tube penetration of the pistil, and eventual self fertilization, that takes place. within a tightly closed flower bud. A single dominant gene (C) controls cleistogamy in this plant. During early blooming period, cleistogamous (CC, Cc) plants produce both chasmogamous (open) and cleistogamous (closed) flowers. Enzymes in various tissues of both cleistogamous and chasmogamous buds were detected by isozyme banding patterns in starch gel electrophoresis. The onset of cleistogamy may be signalled in the calyx and corolla tissues in the early stage of flower development. The levels of specific enzymes (PGM, PGI, G-6PD, PGD, MPI) involved in gluconeogenesis, pentose phosphate shunt and glycolysis in both calyx and corolla tissues of the cleistogamous buds were greatly reduced. These enzymes were present in the pistil and anthers of cleistogamous buds and in all floral parts of the chasmogamous buds.
Rootstock influence on bloom date and fruit maturation of `Redhaven' peach [Prunus persica (L.) Batsch] was studied over a 3-year period. Rootstock included seedlings (Lovell, Halford, Bailey, and Siberian C) and cuttings (GF677, GF655.2, Damas 1869, and `Redhaven'). Bloom dates of the various combinations differed in all 3 years, with a range of 3.6, 9.1, and 7.3 days in 1988, 1989, and 1990, respectively. Fruit development period differed each year with a range of 3.9, 5.8, and 4.4 days in 1988, 1989, and 1990, respectively. `Weighted-average harvest date also differed with a range of 3.6,2.9, and 5.6 days in 1988, 1989, and 1990, respectively. `Redhaven'/Lovell was the latest blooming and maturing combination in all 3 years of the study.
We determined the influence of demographic characteristics and floral knowledge (measured as product experience) on the type of floral product purchased. A sample of 401 Pennsylvania residents was divided into fresh flower and flowering plant consumer segments. Results of discriminant analyses showed the two segments were moderately distinct. Purchasers of fresh flowers were younger and more likely employed outside the home than those who purchased flowering plants, but the latter had more blooming plants in their homes than did consumers of fresh flowers. Consumers of flowering plants and of fresh flowers did not differ in their level of floral knowledge or demographic characteristics. Minor differences were found between the two segments that were not substantial enough to justify distinct marketing strategies.
The author investigated, recorded, observed and analyzed the major wildflowers in Mount Huangshan---the natural and cultural heritages listed by the ESC0 of UN for the first time. On the basis of their desirable characteristics, more than 300 wild ornamental species are divided into 8 categories -–-historical old trees, rare and endangered species, evergreen ornamentals, blooming trees and shrubs, plants with colored foliage and fruit in fall, vines, herbaceous ornamentals and ground covers, and ornamental ferns. Mount Huangshan is one of the richest regions of native ornamentals in Eastern China and the most famous natural beauty in Pan-China. There are about 1500 wild landscape plants in and around it. Finally the paper puts forth some proposals and methods for introduction and utilization of wild ornamental plants. That is, investigation, classification,acclimatization and cultivation of them, and building a sort-out botanical garden for the germplasmic preservation and the flourishing landscape tourism.
Abstract
Temperate zone (deciduous) fruit crops are cultivated largely in areas far removed from their center of origin. Selection and breeding have improved climatic adaptation in these perennial crops. Current breeding programs are attempting to broaden this adaptation by developing cultivars with high mid-winter cold tolerance, late blooming to avoid spring freezes, and increased disease resistance. The attainment of these and other breeding objectives will recessitate the use of noncommercial exotic germplasm. The range of these fruits also is being extended to the subtropics and tropical highlands through selection and breeding. It is only through genetic manipulation that more productive and adapted plant materials are likely to be developed. Germplasm centers are needed to maintain and provide the array of genetic variability necessary for continued scion and rootstock improvement.