This research was supported by the Florida Agricultural Experiment Station and grants from the Gloeckner Foundation and the Florida Caladium Growers Association, and approved for publication as Journal Series R-08379.
Gary J. Wilfret, B.K. Harbaugh, and B.D. Miranda
Zhanao Deng and Brent K. Harbaugh
This research was supported by the Florida Agricultural Expt. Station and grants from the Florida Caladium Growers Association and the Gloeckner Foundation. We thank Richard Kelly, Nancy West, Joyce Jones and Gail Bowman for their excellent
Brent K. Harbaugh, B.D. Miranda, and G.J. Wilfret
This research was supported by the Florida Agricultural Experiment Station and grants from the Gloeckner Foundation and the Florida Caladium Growers' Association, and approved for publication as Journal Series R-08380.
Fahrettin Goktepe, Zhanao Deng, Brent K. Harbaugh, Teresa Seijo, and Natalia A. Peres
Caladiums, widely used in containers and landscapes as ornamental plants for their bright colorful leaves, are generally forced or grown from tubers. Commercial production of these tubers in central Florida is through dividing “seed” tubers and growing them in fields. Tuber quality is therefore of critical importance to success in container forcing, landscape use, and tuber production. Fusarium tuber rot (Fusarium solani) has been recognized as the most-destructive disease that affects caladium tuber quality. There is anecdotal evidence from growers indicating the existence of resistance in commercial caladium cultivars. To identify and confirm the source of fusarium tuber rot resistance in caladium, F. solani isolates have been collected from rotting tubers grown under different soil conditions and from different locations. The pathogenecity of these isolates has been tested through artificial inoculation of fresh harvested and/or stored tubers, and a number of highly virulent isolates have been identified. These isolates have been used to refine inoculation and disease evaluation techniques. Two techniques, spraying a conidial suspension onto fresh cut surfaces and inserting Fusarium-infested carnation leaf segments into artificial wounds, have proven to yield consistent resistance/susceptibility ratings among cultivars of known difference in resistance to fusarium tuber rot. Appropriate incubation temperatures and humidity seem to be very critical for disease development and evaluation. The two techniques have been used to evaluate 35 cultivars. Several cultivars, including `Candidum', showed a high level of resistance to fusarium tuber rot, and may be good breeding parent for developing new resistant cultivars.
Zhanao Deng and Brent K. Harbaugh
As a common pot and landscape plant, caladium ( Caladium ×hortulanum Birdsey, Araceae Juss.) is valued for its colorful leaves and low maintenance requirements ( Evans et al., 1992 ). Commercial caladium plants are grown from tubers. Central
Charles F. Gager and Gary J. Wilfret
The mode of leaf spot color, venation color and pattern inheritance and differences in the apparent strength of leaf petioles were investigated. Progeny from self pollinations of Caladium bicolor cv. Painter's Palette and two commercial cultivars (`Florida Cardinal' and `Aaron') were utilized in a pedigree and back cross breeding program to delineate and prove a proposed model for the mechanisms controlling spot and vein color inheritance as well as the inheritance of venation patterns. Differences in the apparent strength of leaf petioles in Caladium were observed in the field, Anatomical and mechanical analysis using a Kramer Shear Cell, showed significant differences among 12 experimental lines, The relative strength of the petioles were correlated to petiole pigmentation, with darker colored petioles being stronger and less prone to bending than lighter colored petioles.
Gary J. Wilfret
Two lance-leaf caladium cultivars are to be released from the ornamental breeding program at the University of Florida. `Red Ruffles', whose pedigree is Red Frill × (`Red Frill' × `Candidum Jr.'), has elongated medium red leaves with ruffled green margins. Plants are upright with strong petioles, have leaf blades 25 cm long and 14 cm wide, and attain a height of 61 cm when grown in full sun in the field. Plants have more leaves and are more cold tolerant than `Red Frill', the major red lance-leaf cultivar of commerce. Tuber yields of `Red Ruffles' are similar to `Red Frill' but less than `Rosalie', with production indices of 95.0, 97.8, and 121.0, respectively. Foliage of `Red Ruffles' is more upright and less likely to elongate under reduced light than the other cultivars. `Irish Lace', an F2 selection from a cross of “Candidum Jr.' × “Red Frill', has elongated dark green leaves with heavily ruffled margins, which are etched with a thin red border. Leaf blades are 26 cm long and 8 cm wide and have heavy substance. Plant height is 65 cm in the field. Tuber yields of `Irish Lace' are greater than `White Wing', a major green/white cultivar. Use of a green caladium would be as a border or a mixture with red or white lance-leaf cultivars.
Zhanao Deng and Natalia A. Peres
Caladiums ( Caladium × hortulanum Birdsey, Araceae Juss.) can be grown in containers or planted in the landscape as accent and border plants ( Evans et al., 1992 ). They are valued for their long-lasting colorful foliage. Most of the commercially
Zhanao Deng and Brent K. Harbaugh
Caladiums ( Caladium ×hortulanum Birdsey, Araceae Juss.) are often used to provide color and a tropical ambiance to container gardening or the landscape ( Evans et al., 1992 ). Approximately 95% of the caladium tubers used in the United States and
Eakhlas U. Ahmed, Takahiro Hayashi, and Susumu Yazawa
The developmental pattern of leaf color distribution during plant development in 10 cultivars of Caladium ×hortulanum Birdsey was investigated. We used the color occupying the largest area in the terminal leaf as the dominant color, and expressed the leaf color stability during plant development by the ratio of the percentage of the dominant color area in the terminal leaf to that of the dominant color area in the initial leaf (leaf color stability index). In some cultivars, leaf color stability index was clearly greater than 1 (leaf-color-unstable cultivar), but in some cultivars it was close to 1 (leaf-color-stable cultivar). In plants regenerated from leaf explants of leaf-color-unstable cultivars, many (21% to 43%) color variants were observed but only a few (0% to 6%) occurred from leaf explants of leaf-color-stable cultivars. Tissue culture appears to be a useful technique for rapid propagation based on leaf color stability in leaf-color-stable and leaf-color-unstable cultivars.