Progress 12/27/01 to 09/30/05
Outputs
Several categories of orchids have been successful for use as blooming potted plants. Dendrobium orchid is one such category, with increasing popularity in the international floricultural scene for use in offices and homes and for interiorscaping of hotels and restaurants. The main attraction of Dendrobium relative to other potted orchids was reviewed and includes their floriferous flower sprays, a wide range of colors, sizes and shapes, year-round availability, and long flowering life of several weeks to months. Two anthocyanin biosynthetic genes from Dendrobium orchid were characterized to assist in breeding strategies and their complete coding sequences published in GenBank. Virus resistance was identified by lack of foliar symptoms and lack of systemic spread, monitored by tissue blot ELISA, in plants bioengineered with a variant movement protein gene of Cymbidium mosaic virus.
Impacts
Breeding of new varieties of Dendrobium orchid has progressed for both cut flower and potted plant use. The attribute of flower color is being defined at the molecular genetic level. Efforts to produce a virus-resistant dendrobium are progressing. We remain one of the few publicly funded flower breeding programs in the U.S. that fully integrates greenhouse-based hybridization with lab-based discovery research.
Publications
- Kuehnle, A.R. 2005. Orchids, Dendrobium. In: Flower Breeding & Genetics: Issues, challenges, and opportunities for the 21st century (N. Anderson, ed.) Springer Verlag, Heidelberg, pp. 533-554.
- Mudalige-Jayawickrama, R.G., Champagne, M.M., Hieber, A.D. and Kuehnle, A.R. 2005. Cloning and characterization of two anthocyanin biosynthetic genes from Dendrobium orchid. J. Amer. Soc. Hort. Sci. 130:611-618.
- Amore, T.D. and Kuehnle, A.R. 2004. New dendrobium cultivars and update on current dendrobium research. Hawaii Floriculture Conference Maui, March 2004 (K. Leonhardt, P. Nakao, eds.), pp. 50-52.
- Obsuwan, K., Borth, W.B., Hu, J. and Kuehnle, A.R. 2005. Virus resistance in orchid plants transformed with a mutated movement gene of Cymbidium mosaic virus. HortScience 40: 1050.
- Kuehnle, A.R. and Amore, T. 2005. Tropical flower breeding at the University of Hawaii. HortScience. 40:945.
- Kuehnle, A.R. 2005. Adventures in orchid bioengineering for improved color and disease resistance. 16th biennial meeting of the New Zealand branch of the IAPTC&B, pg. 9.
- Mudalige-Jayawickrama, R.G., Champagne, M.M., Hieber, A.D. and Kuehnle, A.R. 2004. Dendrobium hybrid cultivar chalcone synthase mRNA and putative dihyroflavonol 4-reductase mRNA, complete coding sequences. GenBank submissions AY741318-AY741319.
- Borth, W.B., Osbuwan, K., Barry, K., Kuehnle, A.R. and Hu, J.S. 2005. Movement of Cymbidium mosaic virus and transgenic resistance in Dendrobium orchids. Acta Hort. (in press)
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Progress 10/01/03 to 09/30/04
Outputs
Cloning and characterization of two key anthocyanin biosynthetic genes of Dendrobium, dihyroflavanol 4-reductase and chalcone synthase, is nearing completion. A virus resistance gene was introduced into two commercial varieties of Dendrobium x Jaquelyn Thomas via particle bombardment of protocorm-like bodies with 12% to 14% transformation efficiency. Fifty plants of Dendrobium UH800 and 25 plants of Dendrobium UH306 representing a total of at least 25 distinct transgenic orchid lines were identified. Of those plants challenged with a1:1000 dilution of cymbidium mosaic virus, 41% remain free of virus after 9 months. Progress in biotechnology applications in the Orchidaceae since 1997 was reviewed. This review addressed functions of some cloned orchid genes affecting flower induction, flavonoid biosynthesis, flower senescence, and disease defense. Advances made in other applications of biotechnology in orchid production and improvement were also covered including
methods of transgenesis, engineering disease resistance, engineering novel flower colors, engineering for increased vase life, virus detection, antiviral strategies, DNA markers to improve breeding strategy, and flower color gene activity tests.
Impacts
Orchids are one of the fastest growing segments of potted plant market. Dendrobium orchid breeding has benefitted greatly from using molecular tools in understanding genetic control of flower color and disease resistance. Our cloning and characterization of key flower color genes in particular will enable more productive hybridization strategies to be implemented to meet market demands. Our efforts to produce a virus-resistant dendrobium is progressing.
Publications
- Mudalige, R.G. and Kuehnle, A.R. 2004. Orchid biotechnology in production and improvement. HortScience. 39:11-17.
- Kuehnle, A.R., Fujii, T., Mudalige, R. and Alvarez, A. 2004. Gene and genome melange in breeding of Anthurium and Dendrobium orchid. Acta Hort. 651:115-122.
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Progress 10/01/02 to 09/30/03
Outputs
Perianths of 34 Dendrobium species and hybrids were examined to elucidate the roles of pigment distribution and shape of upper epidermal cells in determining color intensity, perception, and visual texture. Anthocyanins were confined to the epidermal layer or subepidermal layer in flowers with low color intensity, whereas they were also in several layers of mesophyll in more intensely colored flowers. Striped patterns on the perianth were due to the restriction of pigment to cells surrounding the vascular bundles. Anthocyanins in combination with carotenoids resulted in a variety of flower colors ranging from red, maroon, bronze to brown, depending on the relative location of the two pigments. Four types of epidermal cell shapes were identified in Dendrobium flowers: flat, dome, elongated dome and papillate. Epidermal cell shape and cell packing in the mesophyll affected the visual texture. Petals and sepals with flat cells and a tightly packed mesophyll had a glossy
texture, whereas dome cells and loosely packed mesophyll contributed a velvety texture. The labella in the majority of flowers examined had a complex epidermis with more than one epidermal cell shape, with papillate epidermal cells being predominant. Dendrobium growers in the State of Hawaii were surveyed in 2001 regarding traits that they would like to see in future varieties of potted dendrobiums intended for export to the continental USA. Results indicate that varietal improvement for the mass market should focus on compact growth, early flowering, full flowers, and an array of color.
Impacts
Dendrobium growers in the State of Hawaii were surveyed regarding traits that they would like to see in future varieties of potted Dendrobiums intended for export to the continental USA. Growers identified traits consistent with the Univ. of Hawaii breeding program's criteria for potted plant desirability. Color and visual texture of orchid flowers can be attributed to the combination of pigments within different tissue layers of the petal and to the shape of surface cells of petals.
Publications
- Mudalige R.G., Kuehnle A.R. and Amore, T.D. 2003. Pigment distribution and epidermal cell shape in dendrobium species and hybrids. HortScience. 38:573-577
- Kuehnle, A.R., Amore, T.D., Mersino, E., Sewake, K. and T. Wagoner. 2003. What do Dendrobium orchid producers want in their potted flowers? Results of a grower survey. Univ. of Hawaii CTAHR Coop. Ext. Ser. Series NPH-8
- Obsuwan, K., Borth, W.B., Hu, J., Barry, K. and Kuehnle, A.R. 2003. Development of transgenic Dendrobium orchids resistant to CyMV. Plant Biology 2003 Program. p. 166
- Kuehnle, A.R. 2002. Orchid Genes and Biotechnology Application. International Symposium on Tropical Floriculture Industry and Biotechnology. National Pingtung University of Science and Technology, Pingtung, Taiwan. Abstracts. pg. 8
- Mudalige, R.G. 2003. Dendrobium flower color: Histology and genetic manipulation. Ph.D. Thesis. Univ. Hawaii, Manoa. 150p.
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Progress 10/01/01 to 09/30/02
Outputs
Seeds from crosses made utilizing desirable, usually amphidiploid, parent were germinated for 2 crosses aimed for potted plant development, 13 for cut flower development, and 4 for purposes such as novelty, germplasm maintenance. An additional dozen crosses were advanced in tissue culture, and other crosses were advanced from transflask, to compot, and into larger containers for flowering. Data collection on over two dozen flowering crosses is underway in the greenhouse. A total of 224 seed pods of 12 different cut flower and potted plant cultivars were provided to three growers associations in 2001. Clonal propagules of D. Ethel Kamemoto and Dendrobium Icy Pink `Sakura' protocorm-like bodies were also provided to growers associations. Expression of two critical genes in the flower color pathway, chalcone synthase (CHS) and dihydroflavonal reductase (DFR), were found to be restricted to the developing flower buds and not detectable in the open flower. One CHS, but not
DFR, was also expressed in leaves. cDNA (RT-PCR) from tight buds was used to extract the genes using degenerate primers. We isolated two forms of CHS, a DFR gene, and partial clones with some sequence similarity to flavonoid 3' hydroxylase and flavonoid 3'5' hydroxylase. One of the potential CHS clones isolated previously was found to encode bibenzyl synthase, closely related to chalcone synthase. The other clone was confirmed to be encoding for chalcone synthase with 90% similarity to the CHS of the orchid Bromheadia at the amino acid level.
Impacts
Good progress was made for every objective of the Dendrobium breeding program in both sexual hybridization and genetic engineering. Numerous seed pods and clonal flasks were provided to the orchid industry and new crosses are underway. Pioneering work on isolation and characterization of Dendrobium gene sequences for critical flower color enzymes is underway.
Publications
- Mudalige, R.G. and Kuehnle, A.R. 2002. Floral flavonoid genes in orchids. In: Plant, Animal & Microbe Genome Conferences. Final Abstracts Guide. Applied Biosystems, Foster City CA. pp. 59.
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Progress 10/01/00 to 09/30/01
Outputs
A complete cDNA clone encoding the anthocyanin biosynthesis enzyme dihyroflavanol 4-reductase (DFR) was isolated from floral buds of lavender Dendrobium. Temporal expression showed DFR transcription throughout bud development, declining sharply just before flower opening. No expression was detected in leaves. The deduced amino acid sequence contains 352 residues of 39.7 kD. Multiple alignment of DFR sequences revealed closest similarity of Dendrobium DFR with the orchids Bromheadia (87%) and Cymbidium (84%). Comparison with 18 other sequences showed 66-74% similarity to other monocots, and 65-72% similarity with dicots. Of interest with DFR enzymes is their substrate specificity for dihydroflavonols. Chromatography of floral anthocyanidins in 22 Dendrobiums showed lavender cyanidin to be predominant. Orange pelargonidin is rare and a major anthocyanidin only in light pink-peach hybrids such as Dendrobium Icy Pink. Pedigree analysis suggests that this novel color
arises from a mutation of two-tone light lavender flowers. Moreover, D. Icy Pink accumulated only kaempferol as the major copigment aglycone while the two-tone parent accumulated kaempferol, quercetin and myricetin. Together these data suggest that the Dendrobium DFR prefers dihydroquercetin as substrate, and in the presence of a mutation accepts dihydrokaempferol to a lesser extent. Northern and enzyme analysis as well as flowering of D. Icy Pink plants transgenic for snapdragon DFR will help elucidate the biochemical and genetic basis for differences in Dendrobium flower color.
Impacts
Floral anthocyanins in flower petals are key attractants of pollinators and consumers alike. The first committed step in the genetically-defined pathway of anthocyanin biosynthesis is the conversion of dihydroflavonols into leucoanthocyanidins by the enzyme dihyroflavanol 4-reductase (DFR). We are characterizing this gene in Dendrobium orchids to directly benefit both ornamental researchers and orchid consumers through directed varietal development.
Publications
- No publications reported this period
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Progress 10/01/99 to 09/30/00
Outputs
Recovery of high-quality RNA from plant tissues is often hindered by the presence of carbohydrates, phenolics, and other compounds that co-precipitate with RNA. A method employing polyvinylpyrrolidone was successful in extracting RNA from Dendrobium perianth, flower buds, and leaves. The average yield of total RNA ranged from 189 microgram per gram buds to 48.5 micrograms per gram leaf. RNA was determined to be of sufficient quality to construct a cDNA library with an average insert size of 1.9 kb.
Impacts
Knowledge of RNA extraction methods for orchids is essential for molecular characterization of transgenic plants and for orchid gene cloning. The reported protocol may be useful for a variety of orchid genera. This will directly benefit orchid researchers and indirectly orchid consumers through varietal development.
Publications
- Champagne, M. and Kuehnle, A.R. 2000. An effective method for isolating RNA from tissues of Dendrobium. Lindleyana. 15:165-168.
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Progress 10/01/98 to 09/30/99
Outputs
Agrobacterium tumefaciens was tested as a bioengineering method for Dendrobium. Protocorm-like bodies of a Dendrobium hybrid, (D. Caesar x D. Waipahu) x D. Waipahu, were co-cultivated with A. tumefaciens strain LBA4301 harbouring the T-DNA plasmid, pUCD2716, and a high copy number virulence helper plasmid, pUCD2614. The T-DNA contained genes encoding hygromycin phosphotransferase (pNOS-hpt) for hygromycin resistance and b-glucuronidase (pCaMV 35S-uidA) for GUS expression. Hygromycin-resistant protocorm-like bodies that survived over 1 year of antibiotic selection were confirmed transgenic for hpt by Southern bolt analyses. DNA near the left border of the T-DNA was not completely integrated as tissues were negative for GUS expression and sequences. This is the first report of Agrobacterium-mediated gene transfer for a highly evolved non-graminaceous monocotyledon and for any orchid.
Impacts
Knowledge of gene transfer methods for orchids permits the next step of creating new orchid varieties with improved economical and aesthetic traits. This will directly benefit the flower industry and flower consumers everywhere.
Publications
- Kamemoto, H., Amore, T.D. and Kuehnle, A.R. 1999. Breeding Dendrobium Orchids in Hawaii. University of Hawaii Press, Honolulu. 166 pp.
- Nan, G.-L., Kuehnle, A.R. and Kado, C.I. 1998. Transgenic Dendrobium orchid through Agrobacterium-mediated transformation. Malayan Orchid Review. 32:93-96.
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Progress 10/01/97 to 09/30/98
Outputs
Dendrobium D'Bush Pansy with regular peloria crossed to normal-lip plants produced offspring with a normal-lip indicating that pansy-lip is recessive to normal-lip. Three F1 offspring backcrossed to the pansy-lip parent produced 1:1 ratios, and one F2 progeny segregated into 3 normal-lip: 1 pansy-lip. Thus pansy-lip is controlled by a single recessive gene pair. The Dendrobium-Agrobacterium interaction was evaluated bichemically using an Agrobacterium/lux gene assay with chromatographically separated orchid tissue exudate to assess vir gene induction. Compound characterization by gas chromatography/mass spectometry identified a water soluble aryl beta-glycoside, possibly conferin, which yields the vir gene inducer coniferyl alcohol. Nuclei were successfully extracted from Dendrobium leaves, pollinia and, to a lesser extent, roots. Yield of 2C nuclei were best from young leaf tissues. In vitro leaf material also provided ample 2C nuclei. Flow cytometric analysis of
young leaf nuclei resulted in accurate detection of ploidy level in the hybrid cultivar D. Neo-Hawaii. Endopolyloidy with ploidy levels up to 16C was found in somatic tissues. 2C DNA content values for 70 orchid species from 26 genera, including 37 Dendrobium species from eight taxonomic sections, were determined using flow cytometry. The resulting nuclear DNA content values for species other than Dendrobium ranged from 1.91 pg 2C-1 to 15.19 pg 2C-1 nuclei for Cadetia taylori and Vanilla phaeantha, respectively. Dendrobium nuclear DNA content values ranged from 1.53 pg 2C-1 to 4.23 pg 2C-1 nuclei for D. cruentum and D. spectabile, respectively. DNA content measurements varied greatly within Dendrobium sections Latouria, from 1.88 pg for D. macrophyllum to 4.23 pg per 2C nuclei for D. spectabile, and for section Spatulata, from 1.69 pg for D. discolor to 4.05 pg per 2C nuclei for D. samoense. The least variation in DNA content was found within the section Phalaenanthe, with values of
1.79 pg to 1.98 pg per 2C nuclei.
Impacts
(N/A)
Publications
- AMORE, T.D. and KAMEMOTO, H. 1997. Inheritance of pansy-lip in Dendrobium. Lindleyana 12:12-15.
- JONES, W.E., KUEHNLE, A.R. and ARUMUGANATHAN, K. 1998. Nuclear DVA content of 26 orchid (Orchidaceae) genera with emphasis on Dendrobium. Annals Bot. 82:189-195.
- JONES, W.E. and KUEHNLE, A.R. 1998. Ploidy identification using flow cytometry in tissues of Dendrobium species and cultivars. Lindleyana 13:11-18.
- NAN, G.-L., TANG, C.S., KUEHNLE, A.R. and KADO, C.I. 1997. Dendrobium orchid contains an inducer of Agrobacterium virulence genes. Physiol. Mol. Plant Pathology. 51:391-399.
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Progress 10/01/96 to 09/30/97
Outputs
The possibility of Cymbidium mosaic potexvirus (CyMV) transmission by individual Dendrobium pollinia from an infected stud plant to an uninfected mother breeding plant during pollination is considered remote. While pollinia from infected plants are found by ELISA to harbor virus, mechanical inoculation of Dendrobium leaves with large numbers of macerated pollinia, 10 to 153 flowers, produced only infrequent (25%) systemic transmission of CyMV. Dendrobium hybrid seedlings derived from parent plants infected with CyMV were tested for the presence of virus to determine if seed transmission occurred during green capsule culture. ELISA tests on 7050 seedlings of seed-propagated D. Jaquelyn Thomas 'Uniwai Supreme' and 'Uniwai Prince' were negative for the virus, indicating that CyMV is not seed transmitted. The genome of tetraploid Dendrobium, at about 4 - 5 pg DNA per 2C nucleus, is found to be of a size suitable for techniques used in molecular breeding.
Impacts
(N/A)
Publications
- KUEHNLE, A.R. 1997. Molecular biology of orchids. In: Orchid Biology: Reviews and Perspectives, VII (Arditti, J., ed.) Kluwer Academic, p 75-116
- PORTER, K., KUEHNLE, A.R., HU, J.S. 1996. Lack of seed transmission of Cymbidium mosaic virus in Dendrobium. Lindleyana 11:211-213
- KUEHNLE, A.R. 1996. Towards control and eradication of virus in Dendrobium by hybridization, tissue culture, and genetic engineering. J. Orchid Soc. India 10:43-51
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Progress 10/01/95 to 09/30/96
Outputs
DNA content values for 70 orchid species from 26 genera, including 37 Dendrobiumspecies from eight taxonomic sections, were analyzed using now cytometry. C-values for species other than Dendrobium ranged from 2.12 pg 2C-1 nuclei for Broughtonia sanguinea to 18.56 pg 2C-1 nuclei for Doritis pulcherrima. Dendrobium C-values ranged from 1.53 to 4.23 pg 2C-1 nuclei for D. cruentum & D. spectabile, respectively. DNA content measurements varied greatly within Dendrobium sections Latouria & Spatulata, from 1.88 pg 2C-1 nuclei for D. macrophyllum to 4.23 pg 2C-1 nuclei for D. spectabile in Latouria, & from 1.69 pg 2C-1 nuclei for D. discolor to 4.05 pg 2C-1 nuclei for D. samoense in Spatulata. The least variation in DNA content was found within the section Phalaenanthe, with C-values of 1.79, 1.86, & 1.98 pg 2C-1 for D. bigibbum, D. affine & D. phalaenopsis, respectively. Observation & evaluation of 23 clones obtained from Thailand and Singapore, representing currently
important or promising clones of both countries, showed the majority to be unsuitable for cut flower production in Hawaii. The Dendrobium-Agrobacterium interaction was evaluated biochemically using an Agrobacterium/lux gene assay with chromatographically separated orchid tissue exudate to assess vir gene induction. Compound characterization by gas chromatography/mass spectometry identified a water soluble aryl B-glycoside, possibly coniferin, which yields the vir gene inducer coniferyl alcohol.
Impacts
(N/A)
Publications
- JONES, W.E., KUEHNLE, A. R., and ARUMUGANATHAN, K. 1995. Nuclear DNA content of eDendrobium orchid species as determined by laser flow cytometry. HortScience. l31:322.
- JONES, W. 1996. Determination of nuclear DNA content in orchids by flow cytometry. M.S. Thesis. Univ. Hawaii, Manoa. 103p.
- KAMEMOTO, H., KUEHNLE, A. R., AMORE, T.D. and SUGII, N. 1995. Observation and evaluation of Dendrobium accessions. Univ. of Hawaii Hort. Digest No. 107:1-5.
- KUEHNLE, A.R. 1995. Blooming Research at the Univ. of Hawaii. Orchid Digest Oct-Dec:183-183.
- KUEHNLE, A.R. and NAN, G.L. 1995. Explosive Breeding in Orchids. Tropical & Subtropical Research Notes. Summer 1995:5, 8-9.
- KUEHNLE, A.R. and NAN, G.L. 1995. Explosive Breeding in Orchids: From Mendel to Molecular. Ka Lono Pua ("The Flower News") 2:3-4.
- KUEHNLE, A.R. and KAMEMOTO, H. 1994. Breeding dendrobiums - the Hawaiian way. In: Kent, L. (ed) Proc. of the 13th Australian Orchid Conf. Orchid Society of the N.T. Darwin p45-50.
- KUEHNLE, A.R. and SUGII, N. 1993. Use of biotech. in breeding Dendrob. orchid. In: Ichihashi, S, Nagata, H (eds) Proc. Nayoga Intl. Orchid Cong. '93. Nayoga Intl. Orchid Show. Japan. p52-54.
- NAN, G.L. and KUEHNLE, A.R. 1995. Methods for orchid genetic engineering. In: T.
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Progress 10/01/94 to 09/30/95
Outputs
Pansy-lip of Dendrobium is a peloric form of the labellum resembling the other two petals. It appeared in Australia in a hybrid named D'Bush Pansy. This crossed to several normal Dendrobium produced normal offspring, indicating that pansy- lip is recessive to normal-lip. Three F1 offspring backcrossed to pansy-lip produced 1:1 ratios and one F2 progeny segregated into 3 normal-lip: 1 pansy-lip. Thus, pansy-lip is controlled by a single recessive gene pair. Four genetic engineering methods - seed imbibition, pollen tube-mediated DNA delivery, electroinjection, and biolistics - were explored with Dendrobium. Transient transformation rate of seeds imbibed in DNA solution was 0.1-0.2%; stable transformation after one year was 0.005%. From over 25,000 seeds resulting from pollen tube- application of DNA, seven (0.028%) plantlets were recovered after 6 to 12 months of selection; no plants survived longer selection. Using 1200 uF capacitance, 500 V/cm for 10 msec, in 40-80
mM KCl medium, an average of 10-16% of electroinjected protocorms expressed transient GUS; a vigorous plantlet was found to contain the neo gene. Biolistic transformation rates were as high as 11.7% and suitable for protocorms, protocorm-like bodies, and etiolated shoots.
Impacts
(N/A)
Publications
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Progress 10/01/92 to 09/30/93
Outputs
Floral characters, meiotic behavior at Metaphase I and sporad formation were compared in three amphidiploids and their diploid counterparts. The flowers of the tetraploids were larger than those of the diploids. The meiotic behavior of the diploids was highly variable with mean configurations ranging from 14.3 bivalents plus 9.4 univalents to 18.9 bivalents plus 2 univalents. In the amphidiploids, nearly all cells had 38 bivalents. Sporad formation also varied; diploids had 36-70% tetrads while the tetraploids had 97-100% tetrads. Preferential pairing and small chromosome size may promote the formation of bivalents in the amphidiploids. In Dendrobium, PPPC tetraploids carry 3 sets of the Phalaenanthe genomes and one set of the Ceratobium genome. Progeny from two groups of 17 PPPC crosses total were evaluated for uniformity, yield, bud drop and other horticultural traits. Of the 17 total crosses, 3 with D. Joanna Mesina as one of the parents produced erect sprays with
low bud drop and long vase lives of 20 to 23 days and will be released as UH1191, UH1276, and UH1233 for trial as seed-propagated PPPC cultivars. The cross between amphidiploid Dendrobium Macrobig and diploid D. spectabile produced offspring with attractive purple-violet, star-shaped flowers with conspicuous white edges on sepals, petals and lip; it was registered and released as D. Pua'ala.
Impacts
(N/A)
Publications
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Progress 10/01/91 to 09/30/92
Outputs
Eleven crosses were made with three clones of Dendrobium Louis Bleriot as femaleparents and three clones of amphidiploid D. X Jaquelyn Thomas and one clone of amphidiploid D. Neo-Hawaii as male parents to substantiate the occurrence of androgenesis. Some androgenetic diploids which strongly resembled the male parents were recovered in 10 out of the 11 crosses. Although the parent plants were infected with cymbidium mosaic virus, the androgenetic diploids were not. Androgenetic selections are being mericloned and treated with colchicine to induce amphidiploids which can be used for producing seed-propagated cultivars. Yield and morphology of 11 diploid Dendrobium hybrids and their corresponding colchicine-induced amphidiploids from intersectional combinations of Ceratobium x Eleutheroglossum, Phalaenanthe x Ceratobium an Phalaenanthe x Eleutheroglossum were compared. In general, the amphidiploids were less floriferous and produced fewer and shorter racemes, but had
greater flower size. Genetically-modified Dendrobium plants were recovered from protocorms treated by microprojectile bombardment and cultured on hormone-free half-strength MS medium containing 100 mg/1 kanamycin. Twenty-one months after treatment, Southern blot analysis of genomic DNA and PCR amplification products verified stable transformation for plantlets recovered from protocorms representing 2 out of four crosses.
Impacts
(N/A)
Publications
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Progress 10/01/90 to 09/30/91
Outputs
One new seed-propagated dendrobium potted plant cultivar, PCE- type triploid Dendrobium Cathy Beck (purple petals, light purple sepals), one new mericloned potted plant cultivar, amphidiploid Dendrobium Mini Pearl laine Fuchigami 4N' (light purple) and two seed-propagated, cut flower cultivars, UH1002 (Jaquelyn Thomas) and triploid UH1041 (Nanae) were released to dendrobium grower associations in Hawaii. Dendrobium dicuphum (semi-alba) x D. affine (alba) resulted in semi-alba offspring. The F2 segregated into 3 semi-alba: 1 alba, indicating the dominance of the gene controlling semi-alba. D. dicuphum (semi-alba) x D. phalenopsis var. compactum
auna Kea' (white) produced uniformly purple offspring through complementary gene action. F2 crosses segregated into 36 purple: 21 semi-alba: 7 white.
Impacts
(N/A)
Publications
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Progress 10/01/89 to 09/30/90
Outputs
Ten out of 11 crosses involving triploid Dendrobium x Louis Bleriot and three clones of amphidiploid D. x Jaquelyn Thomas and one clone of D. x Neo Hawaii produced androgenetic diploid offspring that strongly resembled the male parents. Chromosome numbers of the majority of the hybrid offspring fell between the triploid and tetraploid levels, which is expected for 3N x 4N crosses. Although the parents were heavily infected with Cymbidium Mosaic Virus, the virus was not detected in most of the androgenetic diploids. Two new seed-propagated dendrobium potted plant cultivars, 'Sylvia Yuen' (green-white) and 'Susan Takahashi' (dark lavender) and three seed-propagated, PPPC type, cut flower cultivars, UH800 (Jaquelyn Thomas), UH955 (Joan Kushima) and UH971 (Elaine Harada) were released to dendrobium grower associations in Hawaii. Mesophyll protoplasts of two commercial Hawaiian Dendrobium cultivars were successfully isolated and cultured to yield microcallus.
Impacts
(N/A)
Publications
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Progress 10/01/88 to 09/30/89
Outputs
An excellent opportunity arose to investigate the genetics of flower color involving three early maturing Dendrobium species, D. affine (white), D. dicuphum (semi-alba), and D. phalaenopsis var. compactum 'Mauna Kea' (white), all belonging to the Phalaenanthe section. D. dicuphum x D. phalaenopsis var. compactum 'Mauna Kea' produced uniformly purple offspring. F2 crosses segragated into 36 purple: 21 semi-alba: 7 white. Another cross between D. dicuphum (semi-alba) and D. affine (alba) resulted in semi-alba offspring. The F2 segregated into 3 semi-alba: 1 alba. It was concluded that two complementary gene pairs (C and R) are responsible for the expression of purple color similar to that proposed for Cattleya by Hurst in 1925. In addition, the presence of an independent dominant gene P controls the expression of semi-alba. Two hybrids involving Dendrobium stratiotes were released to dendrobium growers as seed-propagated flowering potted plant cultivars. These are D.
Caesar (D. stratiotes x D. phalaenopsis var. compactum and D. Samarai (D. stratiotes x D. antennatum). The attributes of D. Caesar (UH921) are attractive purple-violet flowers, free of bud drop, free flowering, and compact stature, while those of D. Samarai (UH988) are free-flowering, year-round flowering, short stature, attractive antelope-type flowers that last up to three months, and attractive foliage.
Impacts
(N/A)
Publications
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Progress 10/01/87 to 09/30/88
Outputs
Cymbidium mosaic virus is a serious disease of dendrobium orchids in Hawaii. Symptoms of the disease include foliar pitting or streaking and floral necrosis. Some plants do not express floral necrosis even though they are infected with the virus. These necrosis-free plants were defined as resistant. Crosses were made between resistant and susceptible plants, and seedlings were inoculated with the virus. Susceptible x susceptible crosses produced susceptible offspring, resistant x resistant crosses produced resistant offspring, and susceptible x resistant crosses produced susceptible offspring. Results indicate that expression of floral necrosis is genetically controlled, and expression of necrosis is dominant to non-expression. Sixteen amphidiploid progenies including the five University of Hawaii cultivars released earlier were evaluated to possibly identify new, desirable cross combinations which might complement the presently available cultivars in commercial
production. The UH cultivars were among the eight highest yielding progenies. All progenies produced higher yields during June through November than from December through May, which is typical for amphidiploid cultivars. Each progeny showed weekly fluctuations in yield. By pooling progenies, peaks and valleys of yield were reduced.
Impacts
(N/A)
Publications
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Progress 10/01/86 to 09/30/87
Outputs
A cross between amphidiploid Dendrobium Plum Jade and diploid D. antennatum produced attractive flowering potted plants with exceptionally long lasting flowers. The twisted, upright petals are white toward the base and chartreuse toward the tip. The sepals are white, and the lip is purple. This triploid progeny was registered as D. Sylvia Yuen, and seed pods of the repeat cross were released to growers' associations. Triploid D. Purple Gem crossed to D. bigibbum var. compactum produced a relatively uniform, short-statured, tetraploid progeny with attractive purple flowers. Unreduced triploid eggs from D. Purple Gem were fertilized by normally reduced haploid pollen from D. bigibbum var. compactum to give rise to tetraploid offspring. This cross was registered as D. Karen Nishimoto. Seeds pods are being produced for release. Degradation of flavonoids, carotenoids and chlorophylls in Dendrobium flowers at different stages of maturity within a raceme was examined
for three progenies. The amounts of carotenoids and chlorophylls in two crosses decreased rapidly after blooming, while in one cross a high carotenoid content was maintained in all stages of maturity. Flavonol content in all crosses did not change with maturity. The degradation of carotenoids and chlorophylls in two crosses was associated with the fading of flowers.
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Progress 10/01/85 to 09/30/86
Outputs
The cross between amphidiploid Dendrobium Macrobig and ampihidiploid D. Superbiens was named Carolie Simone and released to the dendrobium industry. This seed-propagated cut flower cultivar produces attractive Red-purple flowers predominantly during the winter months. Keeping quality is excellent, and bud drop is low. It is a trigenome, tetraploid hybrid with two sets of the P (Phalaenanthe) gerome, one set of the C (Ceratobium) genome, and one set of the L (Latourea) genome. A selection from the cross between D. strebloceras and D. canaliculatum was increased through tissue culture, named D. Autumn Lace 'Uniwai Sunset', and released to growers as a flowering potted plant cultivar. This cultivar is short-statured and floriferous, with small but attractive Greyed-yellow flowers borne on erect racemes. The chromosome number of 15 Dendrobium species in the section Ceratobium was uniformly 2n=38. Among 34 accessions of selected cultivars with yellow flower pigments,
21 were triploid, 8 were tetraploid and 5 were diploid. The popular commercial cut flower cultivars, D.Mary Mak, D. Sri Siam, and D. Betty Ho, are triploid.
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Progress 01/01/85 to 09/30/85
Outputs
Advance test of 9 mericloned selections with 6 cooperating growers was concluded. Two selections: Dendrobium Evelyn Nakasato (K251-35) as flowering potted plant, and D. Carey Miller (487-118) for cut flowers, appeared promising to warrant clonal increase by grower for commercial cropping. D. Mini Pearl 'Elaine Fuchigami' (K580-3) with small, lavender flowers on short pseudobulbs, and D. Royal Satin 'Alii' (K217-21) with velvety red-purple flowers on relatively short pseudobulbs, were released to dendrobium grower's associations as potted plant cultivars. Seedlings of a cross (K616) between a white amphidiploid D. Jaquelyn Thomas and a white tetraploid D. phalaenopsis were distributed to cooperators for trial. Also mericloned plantlets of D. Tay Swee Keng with large, dark-lavender flowers were distributed for trial. D. Sri Siam introduced from Singapore in Spring, 1984, has been placed in tissue culture for trial with cooperators. This selection produces long,
sturdy stems carrying flowers with yellow petals and sepals and dark purple lip.
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Progress 01/01/84 to 12/30/84
Outputs
Two new seed-propagated, flowering potted plant cultivars were released to dendrobium growers. UH613, registered as Dendrobium Lynne Horiuchi, is a cross between amphidiploid D. Macrobig (D. macrophyllum x D. bigibbum) and diploid D. bigibbum. The triploid offspring are uniform, compact, and floriferous with relatively small, round and attractive flowers. UH498 is a cross between amphidiploid D. Jaquelyn Thomas (D. phalaenopsis x D. gouldii) and D. canaliculatum. This is a miniature version of the cut flower cultivar, 'Uniwai Supreme' (UH232). Six carotenoids--neoxanthin, violaxanthin, lutein, zeaxanthin and beta-carotene--and chlorophyll a and b were identified. Lutein, zeaxanthin and beta-carotene were the major pigments responsible for yellow flower color in several dendrobiums. Twenty-eight species and 39 hybrids of Dendrobium were collected from Southeast Asia and Japan. These have greatly expanded our germplasm for developing new and improved dendrobium
cultivars.
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Progress 01/01/83 to 12/30/83
Outputs
Among 5 mericloned selections advance tested with cooperating growers in 1982, 2small-flowered selections performed well as potted plants, and therefore were named and released for propagation and distribution by growers' associations. 'Spiral Gem' (K230-15) is yellow with purple lip, and 'Spring Bouquet' is chartreuse to white with lavender lip. Mericlones of the following selections were distributed to cooperating growers for dvance testing in 1983: K318-11 (dark purple), K350-3 (white), K384-30 (white), K487-18 (yellow), K251-35) (large purple) and K364-4 (small yellow). Seventy-five seedlings were selected for observation and evaluation; 80 new crosses were made. Kappa carrageenan processed from the red alga, Eucheuma cottonii, was found to be an acceptable substitute for agar for aseptic culture of dendrobium seedlings. Infection of dendrobium plants with cymbidium mosaic virus increased about 15% per year. Plants resistant to virus induced flower necrosis
were identified and will be utilized for breeding virus resistant cultivars.
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Progress 01/01/82 to 12/30/82
Outputs
The selections, UH503 (purple-violet) and UH507 (light purple-violet), wre named'Uniwai Prince' and 'Uniwai Princess', respectively, and officially released in conjunction with the 75th Anniversary Celebration of the University of Hawaii. These are the fourth and fifth seed-propagated amphidiploid dendrobium cultivars released to dendrobium orchid growers associations in Hawaii. The following miniature-flowered selections were mericloned and plants distributed to five cooperators for advance testing as flowering pot plants: K230-15 (yellow with purple lip), K227-27 (white with greenish lip), and K228-21 (yellow). Mericlone plants of K364-4 (small, yellow flowers) and K251-35 (large purple flowers) are about ready for testing with cooperators. The following promising cut flower selections have been increased through shoot-tip culture for advance testing: K318-11 (purple), K350-3 (white), K384-30 (white) and K487-18 (yellow). Eighty-four new selections were made and
placed under observation and evaluation. Selection and Inbreeding of Amphidiploid Dendrobium Jaquelyn Thomas UH44 strain resulted in larger and whiter flowers but reduced yields.
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Progress 01/01/81 to 12/30/81
Outputs
During the past year we released to the Dendrobium Growers Association of Hawaiiseed pods of two additional seed-propagated, amphidiploid, hybrid cultivars, 'UH503' and 'UH507'. The former is Purple-Violet (RHS Colour Chart 80A), and the latter is light Purple-Violet (RHS Colour Chart 80B). These should complement the cultivars, 'UH44' (pink blush), 'UH232' (two-toned lavender), and 'UH306' (white) released earlier. After several years of evaluation the following selections were considered promising for cut flower purposes, and therefore, are now being increased through shoot-tip culture for eventual advance testing with selected cooperators: K318-19 (purple), K350-3 (white), K384-30 (white), K339-19 (white) and K487-18 (yellow). The following small-flowered but floriferous hybrids appear promising for flowering pot plant production, and are being increased through shoot-tip culture for advance testing: K230-15 (yellow with purple lip), K227-27 (white with greenish
lip), K228-21 (yellow) and K364-4 (yellow with purple lip). Several commercially available mericlone dendrobiums were acquired and placed under observation and evaluation.
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Progress 01/01/80 to 12/30/80
Outputs
In accordance with the request from the Dendrobium Orchid Growers Association ofHawaii we renamed 'UH44', 'UH232', and 'UH306' to 'Uniwai Blush', 'Uniwai Supreme', and 'Uniwai Pearl', respectively. During the year we released to the Association 85 mother flasks and 21 seed pods of Uniwai Pearl, 3 mother flasks and 17 seed pods of Uniwai Supreme, and 26 mother flasks and 11 seed pods of Uniwai Blush. Forty-seven new crosses were made during the year. Several seedlings, mostly with yellow flowers, were selected for observation and evaluation. Twenty-one promising selections were elevated to "advance testing." Three intersectional hybrids involving Dendrobium canaliculatum as one parent are being doubled in chromosome number in meristem culture to produce fertile tetraploids (amphidiploids) for use in our breeding program. Out of 83 plants obtained from mericloning diploid Aranda Wendy Scott, 28 plants (34%) were tetraploid. Diploid plants grew slightly faster than
tetraploid plants, produced more flower sprays, more flowers per spray and longer scapes. The tetraploid plants which arose in meristem culture were considered undesirable mutants for cut flower purposes.
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Progress 01/01/79 to 12/30/79
Outputs
We named and released the third seed-propagated dendrobium cultivar, 'Jaq-HawaiiUH306'. This is a cross between an inbred plant of 'Jaquelyn Thomas UH44' and a tetraploid Den. Neo Hawaii which arose from meristem culture. 'UH306' has larger and whiter flowers and higher yields than 'UH44'. During the year we distributed to the Dendrobium Orchid Growers Association of Hawaii 309 seedling flasks of 'UH44', 390 flasks of 'UH232' and 278 flasks of 'UH306'. Also following the newly adopted policy on cultivar release, we distributed 5 seed pods of UH44, 13 pods of UH232 and 12 pods of UH306. In addition we turned over 72 flasks of recently germinated seedlings. These distributions should fulfill the requirements of growers for seed-propagated cultivars released to date by the University of Hawaii. Through studies of meiosis in species hybrids of Dendrobium and Oncidium, the relationships of species were elucidated. Seeds obtained from dendrobium plants severely
infested with cymbidium mosaic virus produced virus free plants. It was concluded that cymbidium mosaic virus is not transmitted through seed propagation.
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Progress 01/01/78 to 12/30/78
Outputs
During 1978 we distributed to the Dendrobium Cut Flower Growers Association 742 seedling flasks of Dendrobium 'Jaquelyn Thomas UH232' and 10 seedling flasks of 'Jaquelyn Thomas UH44'. Both of these cultivars developed by the University of Hawaii are still in demand and are being cultivated in substantial numbers. A third seed propagated cultivar is undergoing germination and transflasking for release during 1979. This new cultivar is a cross between two tetraploid (amphidiploid) species hybrids, D. Jaquelyn Thomas and D. Neo Hawaii. This cross is uniform and high yielding, but has larger and whiter flowers than 'Jaquelyn Thomas UH44'. Forty-nine crosses were made during the year and 43 seedlings were selected for observation and evaluation. Emphasis has been placed on developing improved yellow cultivars. Pollination studies involving species in the sections Miltoniastrum and Cebolletae of the genus Oncidium showed good cross compatibility. The intersectional
hybrids revealed good chromosome pairing which indicated a close relationship between the Miltoniastrum and Cebolletae sections.
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Progress 01/01/77 to 12/30/77
Outputs
The selected clone of Dendrobium Jaquelyn Thomas designated '66194-7' and released earlier was named 'Nat Seefurth' in memory of the late Nathaniel (Nat) H. Seefurth who supported dendrobium and anthurium research at the University of Hawaii. Some growers who obtained a few plants have subsequently increased this cultivar through tissue culture. During 1977 we made available to growers 340 seedling flasks of 'Jaquelyn Thomas UH232' which was officially released in 1976. We also released 340 seedling flasks of 'Jaquelyn Thomas UH44'. Both of these cultivars are being cultivated by growers in substantial numbers. Twenty eight crosses were made during the year. Fifty one seedling selections were made for observation and evaluation. Self and cross pollinations involving 32 Oncidium, 2 Brassia, 1 Miltonia, 1 Odontoglossum and 1 Rodriguezia species revealed that 68% were self incompatible, 27% were self compatible and 5% showed both self and cross compatible types.
The study confirmed the common occurrence of self incompatibility in the Oncidium alliance.
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Progress 01/01/76 to 12/30/76
Outputs
The cross between 2 amphidiploids ('Jacquelyn Thomas UH44' and 'Jacquelyn Thomas580') was designated 'Jacquelyn Thomas UH232' and officially released to the Hawaii Dendrobium Growers Association. This progeny-tested, new cultivar is highly productive and has attractive two-toned lavender flowers carried on long sturdy racemes. This is the second seed-propagated dendrobium cut flower cultivar developed and released by the University of Hawaii. Growers continued to request seedlings of Jacquelyn Thomas UH44, which was initially released 4 years ago. During the year we made available to the Hawaii Dendrobium Growers Association 228 seedling flasks of UH44, 24 seedling flasks of UH232, and 600 meristemmed plants of 'Jaquelyn Thomas 66194-7' and 'Lady Hay'. Also, we provided 15 flasks each of UH44 and UH232 to the Federation of Hawaiian Orchid Societies comprised of 15 member orchid societies in Hawaii. Because of the anticipated surplus of pink-tinged flowers from
UH44 and because of the need of other colors for florist use, tests were conducted with flower absorption dyes. Among 10 dyes tested, yellow, lavender and red dyes gave excellent results. Forty crosses were made during the year. Ninety-five seedling selections were made for observation and evaluation.
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Progress 01/01/75 to 12/30/75
Outputs
The amphidiploid Dendrobium 'Jaquelyn Thomas UH44' released to growers as seedlings in flasks about 3 years ago have begun to flower, and growers have been happy with the performance of this cultivar. Due to grower demand, we havecontinued to release seedlings through the Orchid Commodity Committee of the Hawaii Association of Nurserymen. Additional mericlones of 'Jaquelyn Thomas 66194-7' and 'Uniwai Profusion' were also released. The cross 'Jaquelyn Thomas UH44' X 'Jaquelyn Thomas 05804N', has produced a relatively uniform progeny withattractive 2-tone lavender flowers carried on long sturdy racemes. Due to growerinterest in this cross, we will germinate seeds and release seedlings in flasks some time next year. Forty crosses were made during the year, several of which were intended for the production of improved yellows. Thirty seedling selectionswere made for observation and evaluation. In Spring, 1973, the project leader spent his sabbatic in Thailand to
complete the manuscript on orchid species of Thailand in collaboration with Professor Rapee Sagarik of Kasetsart University. The book, which treats horticulturally important orchid species of Thailand and features 58 colored plates, was published this year by the Orchid Society of Thailand.
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Progress 01/01/74 to 12/30/74
Outputs
The tri-genome hybrid, Den. Jaquelyn Thomas (Den. phalaenopsis X Den. gouldii) X Den. d'Albertsii was named Den. Uniwai Profusion, and selected seedlings weremericloned and released to Dendrobium growers. Mericlones of a tetraploid Jaquelyn Thomas, 66194-7, was also released. Ninety-eight seedling selections were made during the year for further observation and evaluation. Several polyploid combinations involving the Phalaenanthe and Ceratobium sections including PPPC, PPCC, PPC and PCC have flowered and showed considerable promise as cut flowers. The major weakness appears to be the relatively poor keeping quality. Chromosome numbers of 54 species and natural hybrids representing 13 genera of the Oncidium alliance were determined. The numbers form an interesting aneuploid-polyploid series of 2n=10, 14, 24, 26, 28, 30, 36, 38, 40,42, 44, 50, 56, 60, 72, 84, 112, 126, 133 and 168.
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Progress 01/01/73 to 12/30/73
Outputs
Over 400 flasks of germinated seedlings of 'Jaquelyn Thomas Strain UH 44' were released to date to dendrobium growers through the Orchid Commodity Committee ofthe Hawaii Association of Nurserymen. A new selection, Den. Jaquelyn Thomas X Den. d'albertsii has been mericloned (project 844) and will be released shortly.This white-flowered tri-genome hybrid composed of one chromosome set each of Den. phalaenopsis, Den. gouldii and Den. d'albertsee is exceptionally prolific, although flowers are relatively small. A few amphidiploid progenies flowered during the year and showed considerable promise as possible seed propagated cultivars. Also 2 new crosses with PPPC genome constitution (3 chromosome sets of Den. phalaenopsis and 1 set of Ceratobium) have shown desirable characteristics which warrant selection and further evaluation. Successful doubling of chromosomes of selected clones with colchicine in meristem culture appears to be an excellent tool in improving
cultivars through polyploidy breeding.
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Progress 01/01/72 to 12/30/72
Outputs
Progeny test of tetraploid Dendrobium Jaquelyn Thomas revealed uniformity, high yield, freedom from bud drop, good shelf life and sturdy and attractive sprays. This new seed propagated cultivar was designated 'Jaquelyn Thomas Strain UH 44' and released as seedlings in flasks to commercial cut flower growers through theOrchid Commodity Committee of the Hawaii Association of Nurserymen. Two promising selections, Jaquelyn Thomas X D. d'albertsii and Jaquelyn Thomas 66194-7 are being increased through meristem culture for eventual release. A number of new combinations in the Sarcanthinae group were produced. A combination between Doritis pulcherrima and Ascocentrum miniatum was officially registered as Doricentrum Pulcherrimin. Cytological analysis will be conducted as a substantial number of combinations reach flowering size. The chromosome numbers of 40 species in 6 genera of the Oncidium alliance were determined. Eight of these were reported for the first time:
Oncidium pulvinatum 2n=42; O. ensatum, 2n=56; O. floridanum 2n=56; Brassia allenii 2n=50; B. pumila, 2n=60; Gomesa crispa, 2n=56; Odontoglossum cariniferum, 2n=56; and O. stenoglossum, 2n=56.
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Progress 01/01/71 to 12/30/71
Outputs
As seedling progenies came into flower, exceptional plants were singled out and placed under observation and evaluation. Characters being evaluated are yield, seasonality, quality of flowers and shelf life. Among those that are promising are a pink-tinged, white, tetraploid Jaquelyn Thomas (K44) and Jaquelyn Thomas XD. d'albertsii. Outstanding selections being increased through meristem culture technique (Project 850S) for ultimate release to the orchid industry areD. Neo Hawaii, D. Lady Hay and tetraploid Vanda Miss Joaquim. About 2000 mericlones of Jaquelyn Thomas were released to the orchid industry through the Orchid Commodity Committee of the Hawaii Association of Nurserymen. Additional data were accumulated on chromosome numbers and karyotypes, cross compatibility,and meiotic behavior of hybrids of the Oncidium alliance.
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Progress 01/01/70 to 12/30/70
Outputs
Seven interspecific hybrids of Dendrobium which reached maturity were analyzed for meiotic pairing and microspore division. Two new intersectional hybrids, Phalaenanthe X Eleutheroglossum and Phalaenanthe X Nigrohirsutae, were analyzed for the first time. Both showed poor pairing indicating poor genome homology. Analysis of chromosome transmission in crosses involving polyploids were completed. 2N X 2N produced 2N, 4N X 4N produced 4N, and 2N X 4N and 4N X 2N produced 3N. 3N X 2N and the reciprocal produced predominantly 4N, while 3N X 4N and the reciprocal produced 5N and/or aneuploids between 3N and 4N. Thus triploids (3N) which are generally considered to be poor breeding plants have successfully given rise to tetraploids (4N) and pentaploids (5N) which exhibit superior horticultural characteristics to those with lower chromosome numbers. Based on this investigation, it should be possible to produce at will Dendrobiumplants with the desired chromosome number.
Evaluation of Dendrobium for commercial cut flower production was continued. During the year 123 new selections were placed under evaluation. Six selections show exceptional promise. Among the earlier selections, three outstanding selections are now undergoing multiplication through meristem culture for release to the industry.
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Progress 01/01/69 to 12/30/69
Outputs
Twenty-nine interspecific hybrids of Dendrobium which reached flowering stage were analyzed for meiotic pairing and microspore formation. Pairing at metaphase I varied from 19 complete pairs to only a few pairs and reflected the degree of genome relationships of the parental species. Chromosome numbers of 714 seedlings from the polyploidy breeding experiment were determined. Outstanding seedlings were selected for breeding purposes or for commercial cut-flower evaluation. Chromosome numbers of 29 species of Oncidium were determined. The somatic numbers represented were 26, 28, 30, 36, 38, 40, 42, 44, 50, 54, 56, 60 and 72. Evaluation of Dendrobium for commercial cut-flower production was continued. Promising selections are being propagated through themeristem culture technique (Project 850-S) for future release. Tetraploid VandaMiss Joaquim which originated through colchicine treatment has shown improvementover its diploid counterpart. Attempts are being made
to increase this clone through meristem culture for ultimate release to Vanda growers. Cytogenetic investigations on Sarcanthine and Cattleya alliances were continued.
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Progress 01/01/68 to 12/30/68
Outputs
Chromosome numbers of 21 species of Phalaenopsis and Doritis were established tobe 2n = 38. The numbers for seven species were reported for the first time. Meiotic behavior of several interspecific hybrids was analyzed to clarify species relationships. Studies on Dendrobium species compatibility, karyotypes and genome relationships have been summarized. Several intersectional species hybrids have been successfully flowered. Evaluation of seedling selections for potential commercial cut-flower production was continued. Promising types are being mericloned for possible release to commercial growers. Many species of orchids were collected and introduced from Central America. These have greatly expanded the gene pool.
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Progress 01/01/67 to 12/30/67
Outputs
Chromosome numbers were established for 5 Phalaenopsis species, 3 Bulbophyllum spp., 2 Cirrhopetalum spp., 3 Eria spp., 5 Oncidium species, Angraecum philippinensis, Coelogyne parishii, and Campylocentrum fasciola. Karyotypes of several species were analyzed. All Phalaenopsis species studied to date were determined to be diploid with 38 chromosomes. The chromosome number of Angraecum philippinensis is 2n=36. This is the first case of a sarcanthine orchid with a somatic chromosome number lower than 38. Among the Dendrobium species and putative natural hybrids of the Kingianum complex introduced from Australia, triploid, tetrapld and hexaploid plants were uncovered. A plant of Phalaenopsis Juanita with thick leathery leaves, eavy-textured flowers and sturdy upright inflorescence was determined to be an octoploid with 152 chromosomes. Siblings of this plant were tetraploid.
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