Friday, August 31, 2012

New Cymbidium Benches

My new Cymbidium benches are now finished. Part of the delay was simply getting the shade frame pipes ordered and delivered. Constructing the Jensoa bench elements was fairly easy, especially by having the hardware supply store cut the electrical conduit tubes to size. This bench represents essentially the same growing space I had back in Maryland.

The regular benchtops elements were more challenging for me to complete. It took me a few weeks to find the materials that I could work with for my designs, but I'm happy with the results. Some portions of the shade frames stick out (red flags), but that's okay with me 'cause those are segments where I'll be hanging other orchids.

All in all, my designated growing space is now three times larger than what it was back in Maryland! Now it's time to retrieve my Cyms from boarding and introduce them to their new home.

Thursday, July 12, 2012


After 6.5 years of being away, it is time to return to Fog City! Highlights of the drive will include brief visits with friends and colleagues whom I haven't seen in years, along with some family.

Although the Cymbidiums will be subjected to travel stress, I expect they will, ultimately, be happier in their new environs. I'm certainly looking forward to growing my tracyanum into a specimen plant!

Wednesday, June 13, 2012


I’ve been wondering about orchid colors and color patterns for the past few weeks, in response to an educational program at my local American Orchid Society judging center. I had noticed on the California Sierra Nevada Judging Center’s website ( that they had recently awarded an AQ to Masdevalia Ziegler’s Love, whereby siblings of this grex had different colors and/or color patterns. This range of color diversity seems fairly uncommon to me, which prompted me into doing some research about variation in Cymbidium colors and patterns.

The topics more commonly discussed amongst Cymbidium growers presently seems to be directed to peloric or feathered flowers, and their perceived increasing appearance in the modern hybrids. 

 Cymbidium (Psychotic x Valley Zenith) ‘Barbara Uno’, exhibited at the 2012 Santa Barbara Int'l Orchid Show

 Cymbidium Mimi ‘SanBar Feathered’, exhibited at the 2012 Santa Barbara Int'l Orchid Show

But the discussion below will be directed to the picotee pattern, whereby the margins of the sepals, petals and/or lip have different color than the body of these segments. 

The picotee phenotype has long been recognized in the horticulture industry. For example, Gustav Mehlquist co-authored a research paper sixty years ago discussing the genetics of flower color variation, including the picotee, in carnations (Geissman and Mehlquist, 1947). The picotee can also be seen in Cymbidium species, e.g. Cymbidium bicolor and Cymbidium canaliculatum (check out and some hybrids. 

 Cymbidium (Golden Celebration 'Pink Tinges' x Kirby Lesh 'Fay', HCC/ACS) by Ezi-Gro Orchids (photo taken in greenhouse of Hatfield Orchids)

 Cymbidium (Mighty Sensation x Paul Robeson), exhibited at the 2011 Santa Barbara Int'l Orchid Show.

If you ask any orchid hybridizer, they will likely tell you that flower color is an important consideration in consumer choice for flowers and ornamental plants. There is great interest in cultivars bearing flowers with altered color, hues and patterns. Understanding the mechanisms regulating flower coloration should aid in the breeding of new cultivars. Picotee and bicolor phenotypes are extremely desirable, and are some of the main targets in ornamental flower breeding (Nakatsuka et al, 2011). 

However, becoming familiar with all of the genes involved in pigment biochemistry and genetics is almost like learning how to play chess. There are a multitude of genes, both regulatory and structural, whose individual spatially- and temporally-controlled activity give rise to the final flower color patterns that stand out from the crowd and catch our eyes. Learning the names of these players, how each gene functions, and then using this information to enhance one or more traits in a hybridizing scheme borders on the arcane.

Flower color biochemistry and genetics has been studied in established plant model organisms such as petunia, snapdragon, morning glory, gentian, lisianthus and lily. Within orchids, Phalaenopsis is the leader for the development of molecular genetic tools applied to flower color variation. Only two of the known pigment genes have been cloned from Cymbidium: the chalcone synthase (CHS) gene (GenBank EU045579.1; Cymbidium floribundum) and the dihydroflavonol 4-reductase (DFR) gene (GenBank AF017451.1; unnamed Cymbidium hybrid).

Flower colors are made up of a combination of flavonols, flavones, and anthocyanins. Flavonols and flavones are two common co-pigments often associated with anthocyanins. They play an important role in determining flower color since they can form complexes with anthocyanins. Most flavones and flavonols are colorless; they appear to provide ‘body’ to white, cream and ivory-colored flowers. Since flavonols and flavones share common precursors with anthocyanins, down-regulation of flavonols/flavones often reduce anthocyanin levels (To and Wang, 2006). Anthocyanins accumulate in vacuoles or anthocyanoplasts. The colored anthocyanins can be further chemically modified by glycosylation, acylation or methylation in a plant species-specific manner.

Spatio-temporal inactivation of Myb
In many plant species, many flavonoid structural genes (the genes that encode the enzymes that synthesize flavonoids and anthocyanins) are co-regulated by transcription factor genes belonging to three gene families: Myb, bHLH, and WDR. Each gene family can have dozens of representatives, e.g. Myb-1 to Myb-15, each with its own purpose, but which may or may not functionally overlap with another Myb family member. Importantly, Myb-bHLH-WDR protein complexes regulate not only anthocyanin biosynthesis but also generate plant epidermal cellular diversity, which includes the different cell types of the flower (Nakatsuka et al, 2008).

Transgenic technology is being used not only to better understand mechanism of pigmentation, but also to increase the diversity of flower colors. Nakatsuka et al (2011) introduced an engineered transgene to silence the Myb3 locus, which regulates the pigmentation of gentian flowers. Starting with a blue-flowered gentian cultivar, Nakatsuka et al obtained ten stable, transgenic lines that showed no color changes, but two lines that produced white-centered flowers with a blue picotee, indicating that the Myb3 locus was silenced in the central part of the flower but not along the petal margins. Nakatsuka et al showed that expression of some anthocyanin-producing genes, e.g. flavanone 3-hydroxylase (F3H), are significantly reduced in the central flower portion, but not along margins, which is consistent with the known Myb3 activity. However, Nakatsuka et al did not explain why the silencing construct, although expressed in petal margins, does not reduce anthocyanin production along petal margins.

Yamagishi (2011) described the spatial and temporal expression of Myb12 in the ‘Sorbonne’ lily cultivar.
 (Google image search;
Myb12 expression is lower during the earlier and later stages of tepal development, and highest during the middle stages. Myb12 expression is also highest in the central tepal regions, with decreasing levels in the intermediate regions, the lowest expression in the margin tissue. This spatial and temporal expression pattern correlates with the darker pink pigmentation in the central flower portion and the white picotee margins. What is not yet known is the molecular basis for these spatio-temporal differences in Myb12, as compared to lilies that do not show the picotee phenotype.

Inactivation of Chalcone Synthase
Morita et al (2012) teach that bicolor flower traits in Petunia are caused by the spatial repression of the chalcone synthase A gene, which encodes an anthocyanin biosynthetic enzyme. While other biosynthetic genes are expressed equally in both the pigmented and white tissues, the suppression of CHS-A in the white tissue is sufficient to result in the white color. The regulatory gene that specifically governs the spatial regulation of CHS-A expression, but not the other pigmentation genes, giving rise to the picotee phenotype, is unknown. The picotee phenotype appears to be a recessive phenotype.

Change in Cell Fate
Broderick (2011) described a new Petunia picotee, whereby the margin tissue is green. 
In this cultivar, a transposable element inserted into the floral binding protein 2 (fbp2) gene, which promotes flower development over epidermal leaf tissue. Decreased expression of fbp2 in petal margins causes the induction of green margin phenotype, including the formation of epidermal tissue with stomata and tricomes. The trait is inherited as a single-gene, homozygous recessive pattern.

Somatic ploidy conversion
De Schepper et al (2001) described azalea sports having a broad, white picotee, whereby the petal edges proved to be tetraploid (4N) tissue but the rest of the flower tissue was diploid (2N). However, it is unclear why during petal development there would be a switch from 2N to 4N cell development, nor why the ploidy conversion would affect pigmentation. De Schepper et al indicate that this somatic 2N to 4N picotee phenomenon is apparently unique to these azalea sports (De Schepper, 2004).

Methods to select for picotee
Fukuta et al (2009, 2010) describe methods of selecting for picotee traits in Lisianthus, the methods comprising the steps of cultivating the plants at temperatures at or below 20 deg C. Selection at the lower temperatures in which the picotee phenotype became clear was effective for improving the stability of the picotee formation in subsequent generations. Fukuta et al suggest that selection of picotee formation stability in seed (pod) parents that show the flavonoid-type picotee is more effective for improving stability than selection of the pollen parent. Fertilizer application can also positively influence the coloring rate, but the degree of influence depended upon the picotee stability of each cultivar

It appears that pigmentation of the petal margin tissue is regulated differently than in the central portions. One hypothesis to explain this difference is that there may be a gradient of transcription factor expression along the petal axis, resulting in spatial differences in pigmentation. A second hypothesis is that changes in gene dosage, either through ploidy conversion or epigenetic mechanisms, can result in the silencing of some pigmentation genes. At this point in time, more molecular genetic tools need to be developed so that we can improve the measurement of changes in gene expression during the many spatial and temporal stages of flower development. Even in the model horticultural plants, there are still more questions than answers to explain the mechanism of picotee development.

 Dianthus ‘Siskin Clock’, Google Image search (

What I think would be really exciting to see Cymbidium flowers having a bold picotee pattern such as Siskin Clock. Even though the picotee and bicolor phenotypes are extremely desirable, and are some of the main targets in ornamental flower breeding (Nakatsuka et al, 2011), it’s not clear to me that the leading Cymbidium hybridizers have pursued a picotee breeding program. But if the buying public shows some economic appreciation towards these color patterns, then perhaps we’ll begin to see some real trait improvements in the near future Cymbidium hybrids.

Geissman and Mehlquist, Inheritance in the Carnation, Dianthus caryophyllus. IV. The Chemistry of Flower Color Variation, I, Genetics 32:410-433, 1947. 

To and Wang, Molecular Breeding of Flower Color, in Floriculture, Ornamental and Plant Biotechnology Vol. 1, Chapter 35: 300-310, 2006.

Nakatsuka et al, Production of picotee-type flowers in Japanese gentian by CRES-T, Plant Biotechnol. 28: 173-180, 2011. 

Nakatsuka et al, Identification and Characterization of R2R3-Myb and bHLH Transcription Factors Regulating Anthocyanin Biosynthesis in Gentian Flowers, Plant Cell Physiol. 49(12):1818-1829, 2008. 

Yamagishi, Oriental Hybrid Lily Sorbonne Homologue of LhMyb12 Regulates Anthocyanin Biosynthesis in Flower Tepals and Tepal Spots, Mol. Breeding 28:381-389, 2011. 

Morita et al, Tandemly Arranged Chalcone Synthase A Genes Contribute to the Spatially Regulated Expression of siRNA and the Natural Bicolor Floral Phenotype in Petunia hybrida, The Plant Journal 70:739-749, 2012. 

Broderick, Jewels in the Genome: Green Picotee Petunia, 2011. (

De Schepper et al, Somatic Polyploidy and its Consequences for Flower Coloration and Flower Morphology in Azalea, Plant Cell Rep. 20:583-590, 2001. (

De Schepper et al, Somatic Polyploid Petals: Regeneration Offers New Roads for Breeding Belgian Pot Azaleas, Plant Cell, Tissue and Organ Culture 76:183-188, 2004. 

Fukuta and Shibata, Influence of Fertilizer Application on Coloring Area Rate in Picotee Petals of Eustoma grandiflorum (Raf.) Shinn., Hort. Res. (Japan) 8(2):187-192, 2009. 

Fukuta et al, Environmental Variation and Selection Efficiency of Picotee Colored Area Rate on Petals in Lisianthus (Eustoma grandiflorum Raf. Shinn.), Hort. Res. (Japan) 9(3):255-261, 2010.

Tuesday, March 20, 2012

2012 CSA Congress

This year's Cymbidium Society of America Congress, concurrent with the SBIOS (prior post), was another quality symposium. There were two Paphiopedilum talks, presented by Masayoshi Takahashi of Tokyo Orchid Nursery and Gail Schwart of the American Orchid Society; three Cymbidium talks, presented by Collin Gillespie, Dr. Randall Robinson on behalf of Dr. Julian Coker, and Kevin Hipkins; and two, what I will categorize as conservation talks, presented by Dr. Lauren Coker and Dr. Holger Perner.

Masayoshi (a.k.a. Ma-Chan) Takahashi is following in the footsteps of his father and grandfather in regards to line-breeding of the Paph. bellatulum and Paph. rothschildianum, thereby representing over 40 years of orchid husbandry. He has presently achieved at least a fourth generation of bellatulum line-breeding from the original wild collected plant, improving upon both coloration and size. Ma-Chan described some of the history of Paph. rothschildianum 'Perfection', FCC/AOS, GM/JOGA, which was chosen from 50 blooming seedlings from amongst 2500 blooming seedlings from amongst 4000 potted seedlings of Paph. rothschildianum 'Millais' x 'Val' (50/2500/4000). Other examples of this Paph. rothschildianum line-breeding were present in his display in the SBIOS. I had the pleasure of clerking for the CSA judging team that evaluated the Paph's of the TON exhibit, and appreciated the discussion of these improved Paph species and hybrids.

Gail Schwartz discussed the present AOS standards for judging Paph. charlesworthii clones, in light of the line-breeding to improve different color, size and shape characteristics. Because of the breadth and depth of her presentation, Gail's talk was somewhat overwhelming to some audience members. However, I thought it was fairly representative of what AOS student judges need to go through to become knowledgeable of the subject matter. Her talk is to be published in the AOS Orchids magazine as a three-part series.

Gail's talk spurred discussion later in the Congress session pertaining to the arbitrary selection manner regarding the practice of species line-breeding. While certain traits may be selected for and enhanced, there is a loss of other traits (syn. genetic diversity) simply because the person who is doing the selection has established an arbitrary key of 'desirable' and 'undesirable' traits. To put it another way, and to paraphrase the issues Dr. Robinson raised, if one is selecting for Great Danes of the dogs, then one is also selecting against those genes that give rise to the Chihuahuas. I'm not a fan (the essence of arbitrariness!) of Chihuahuas, so let's change this example to.... Corgies. I think they're cute. Remember, beauty is in the eye of the beholder. Now consider the Great Danes and/or Chihuahuas and/or Corgies to the wolves, from which all domestic dogs are derived. Should we really consider the line-bred, human-derived 'species' as legitimate representatives of the species found in nature?

I had the real pleasure of visiting with Collin and Karen Gillespie over several days during the Show. What a lovely couple! Collin described his cultural practices to achieve the Cymbidium flower quality for which he is well-known. Collin described paying attention to light and temperature requirements to maximize plant growth during that part of the season, but also the use of an aerated drip system to control (efficient) water/fertilizer use. Aeration may be achieved by use of an air-pump, an air-stone and/or H2O2 to oxygenate the water.

Kevin Hipkins of Royale Orchids gave the Congress' evening plenary talk. Kevin is an entertaining and colorful person! He described his hybridizing programs using Cym. erythraeum and Cym. tracyanum to achieve new colorforms within hybrids. I particularly liked Cym. Chocolat Honeycomb. Here's a conceptual pic of this hybrid. Think chocolate petals and sepals surrounding the honey-colored, tracyanum lip. Are you salivating? Shortened breath intake, with excitement? Now you know I felt when I saw Kevin's slide of this Cymbidium hybrid. De-lish!

Dr. Randall Robinson presented a slideshow of Dr. Julian Coker's orchid collection. There appears to be a multitude of high quality orchids in the Coker collection, and many of the Cymbidiums shown were stunning. It appears that many Cymbidiums of the Coker collection are one-of-the kind and/or rarely seen historical hybrids, so it is important to get many of these preserved for posterity.

Dr. Robinson mentioned that Dr. Coker is one of his orchid mentors, and the importance of having such. So here, I feel the need to acknowledge both appreciation and gratitude for my orchid mentors and friends, which include Dr. Robinson and George Hatfield, and many others, including members of the Torrence Cymbidium Society who make my visits to the Santa Barbara show such a fun vacation.

Speaking of conservation, Dr. Holger Perner described his efforts to develop a breeding program within the Huanglong Nature Reserve in China to preserve the local Paphiopedilums and Cypripediums via in situ mass seedling production, and hopefully thereby reduce the practice of collecting wild species. Dr. Perner showed some beautiful slides of the region and terrain in which he studies.

The Hengduan Mountain Biotechnology (of which Dr. Perner is a partner) exhibit in SBIOS featured a rarely seen Cym. sichuanicum. This species has a lovely(!) fragrance. The flower segments open up fairly closed, reminiscent of Cym. wenshanense (also fragrant), but somewhat later approach the openness of Cym. insigne. Note the honey orange-colored segments.

I think the most inspirational talk of the Congress goes to Dr. Lauren Gardiner, Assistant Botanist at the Royal Botanic Gardens, Kew. Major kudos to CSA Congress organizer Lucia Brandt for securing Dr. Gardiner's participation!

Dr. Gardiner (Lauren) described the Writhlington School Orchid Project (, whereby schoolkids learn to perform tissue culture orchid seed germination, become responsible to grow different orchid genera, engage in real-world orchid conservation projects, human economics and poverty, and develop business practices to provide funding for program development and continuation. Part of the WSOP includes collaboration with Mohan Pradhan, a speaker at last year's CSA Congress. I appreciated seeing slides of Mohan and his achievements in Sikkim. After Lauren's talk, Lucia challenged the Congress participants to think about how we might create an analogous project here within the U.S. In a personal conversation with Lauren, she mentioned that the Arizona Orchid Society ( has developed a similar community outreach project to work with local schools. So at least there is at least one U.S. orchid society model from which our local orchid society may develop an analogous program.