Monday, February 20, 2017

New York Orchid Show 2017: Thailand

New York Orchid Show 2017: Thailand
My favorite time of year has come around yet again.  The days are getting warmer and lighter, and the orchid show has opened at the New York Botanical Garden.  This year's theme is Thailand.  The show's typical lush displays of color feature many Vanda orchids, which are native to Southeast Asia.

I'll be putting up many more pictures from the show in the coming days, but here is a preview of what is to come:

I got to the garden right as it was opening, avoiding much of the crowds that would descend on the orchid show later in the day.
Phalaenopsis orchids arranged to resemble palm trees

Miniature orchids display
Deep purple variety of Dendrobium kingianum

Zygopetalum flowers
A rainbow of vandas so colorful, they don't even look quite real
Dendrobium hybrid

Many colors of dendrobium hybrids

Morning light shines through Oncostele Wildcat

More Oncostele Wildcat flowers

Thursday, February 2, 2017

Vanda Tristar Blue

Vanda Tristar Blue
I visited the New York Botanical Garden a couple weekends ago.  They had just finished their annual Trains Show, which takes over much of the conservatory during the holiday season.  The Orchid Show starts later this month, but until then, the gardens become a quiet and peaceful place to catch a break from the winter outside.  Midwinter is also a great time to see the garden's Vandas at their best.  But the time the Orchid show opens up in a few weeks, many of these flowers will be starting to fade.
Vanda Tristar Blue
Vanda Tristar Blue is a 2004 cross between Vanda Kimigayo and Vanda Manuvadee.  The hybrid has a nice mix of the the blue tones from Vanda Manuvadee, while maintaining the neater petal shape of Vanda Kimigayo.
Parentage of Vanda Tristar Blue (V. Kimigayo x V. Manuvadee)
Image Credits:
Vanda Manuvadee 'Sky',  photo by Cbaile19 (Wikimedia commons image)
Tracing out the genealogy of Vanda Tristar Blue turned out to be somewhat of a challenge.  It's not the biggest genalogy I've trace (Oncidopsis Yellow Parade currently holds that honor, with 70+ crossings in its background).  However, as you can see below, there is a fare share of crossing the same hybrids over and over again that creates a bit of a tangled mess in the background of Vanda Tristar Blue. (Link to full-resolution image)
Genealogy of Vanda Tristar Blue
I tried to emphasize in the image how much just two vanda species (Vanda coerulea and Vanda sanderiana) contributed genetically to Vanda Tristar Blue.  Vanda sanderiana participated directly in 16 of the 39 crosses depicted here (just over 40%), and Vanda coerulea was crossed 6 times into the lineage. Meanwhile, Vanda Roschildiana, a primary hybrid between V. sanderiana and V. coerulea, adds to 5 more crossings in this tree.

Species progenitors of Vanda Tristar Blue
Photo credits:
Vanda sanderiana (original image, by Dalton Holland Baptista, Wikimedia commons)
Vanda coerulea (original image, by  Association Auboise d'Orchidophilie Exotique)
Vanda dearei (original image, by Rachmat Setlawan Saleh (Flickr gallery))
Vanda luzonica (original image,  by Akatsuka Orchid Gardens (orchid vendor site)
Vanda tricolor (original image, by Association Auboise d'Orchidophilie Exotique)
Vanda curvifolia (original image, by Association Auboise d'Orchidophilie Exotique)
The 5 species that contributed to Vanda Tristar Blue are the same as the progenitors of Vanda Roslyn Rogers, and are just one species short of the list for Vanda Pachara Delight.  These three hybrids have very similar genealogy traces as well, dominated by V. sanderiana and V coerulea. Looking at the species progenitors gives a hint why those two species are so important in vanda breeding.  If you want blue, breeding with V. coerulea is the only way to achieve it.  Meanwhile, V. sanderiana has the full-shaped waxy petals that often seem so desired in orchid hybrids.

I imagine I'll profile a few more blue vandas before I'm done, and I look forward to seeing what other commons threads I can find in their lineages.

Monday, January 16, 2017

Dendrobium kingianum: the pink rock orchid

Dendrobium kingianum
Dendrobium kingianum is an Australian species popular among orchid growers. I love the delicate coloring of these flowers, and hybridizers must have too; Dendrobium kingianum has provided either the pollen or the seed to 158 registered crosses!

In its natural environment, Dendrobium kingianum usually grows in or around rocks (as a lithophyte), across much of eastern Australia, covering many habitats and weather patterns. I suspect that this variety of natural growth conditions is why Dendrobium kingianum is reputedly easy to grow in culture.
Closeup of Dendrobium kingianum flowers
Dendrobium kingianum flowers are about 1 inch across.  Lavender varieties like the one I photographed at the Bronx Botanical Garden are the most common.  However, flowers can range from white to deep purple. Australian Native Plants Society has some beautiful photos of purple and white varieties.

Dendrobium kingianum culture notes. (Massachusetts Orchid Society)

Saturday, January 7, 2017

What causes a phalaenopsis to grow a keiki?

Phalaenopsis keikis: Noid Phal keiki on left, Phal Gold Tris keiki on right
Happy 2017 everyone! December/January tend to be a colorful time for orchids in my terrarium.  The shorter, colder days of September provide the perfect signal to induce my Phals to spike.  The flower spikes generally develop over the next two months, and come into full bloom around the turn of the new year.

However, this year, some of my spikes started growing aerial plantlets (or keikis) in addition to flower buds.  The keiki on my noid phal looks like a leaf growing off the side of a new flower spike.  Meanwhile, Phal Gold Tris produced a tiny plantlet at the tip of an old spike that bloomed over the Summer.

I have written about growing and separating phalaenopsis keikis in the past, but this time I was curious about what caused my orchids to produce keikis in the first place.

What causes a phalaenopsis to grow a keiki?

The internet has many claims about what causes an orchid to make a keiki, but offers little evidence in support.  And even in the research literature, I struggled to find a definitive answer.

So what do we know about Phalaenopsis keikis?  I found a common claim that if a phalaenopsis with a new spike (<4 inches) is exposed to temperatures above 28C (82F), then the spike will develop keikis instead of flower buds.  

See examples:
if a plant with a young inflorescence (less than 4 inches or 10 cm) is subsequently grown at 82 F (28 C) or higher, a spike can form a vegetative air plantlet known as a “keiki” instead of flower buds, buds may abort or both. (Phals article from  
"if a plant with an inflorescence <10cm is subsequently grown at 28C or higher for extended periods, a spike can form a vegetative air plantlet referred to as a "keiki" instead of flower buds, buds may abort, or the stem may elongate indefinitely without open flowers [Sakanishi et. al 1980]"  (Roberto G. Lopez and Erik S. Runkle, 2005)
However, when I tried to find the original source for this claim, its evidence is weak.  Sakanishi et al is a 1980 paper describing the Effect of Temperature on Growth and Flowering of Phalaenopsis amabilis. However, this paper never actually reported any keikis!

In fact, the authors found that high temperatures caused flower spikes to abort growth and flowering.
With the object of determining the effect of high temperature treatment started from the different stages of stalk elongation, 12 plants in the greenhouse were shifted to minimum 28C at each time when flower stalks reached a length of 5, 10, 21-30, and 41-50 cm.  The high temperature from the 5cm stage caused the abortion of florets or the stunted growth of the flower stalks. After the stalks elongated more than 10cm, every stalk normally developed into flower even at the high temperature.
 In the closing remarks, the paper references an even older study on Phalaenopsis schilleriana, which makes the claim about keikis being triggered by temperature.
At ...(maximum temperature 29-34C; minimum temperature 24-25C), [Phalaenopsis schilleriana]  adult plants develop a stalk, which remains vegetative and develops an adventive plant.           (De Vries JT, 1953)
This paper "On the flowering of Phalaenopsis schilleriana" dates back to 1953, and is not available online.  Thus we only have a second-hand description of its findings from the Sakanishi paper.  However, it appears to be the sole parent of all the claims regarding temperature control inducing keiki formation.

What does keiki paste do?

A number of companies sell a product called "keiki paste" which when applied to a dormant node on a flower spike can help induce growth of a keiki.  The active ingredient of keiki paste is a chemical called BAP, or benzyl adenine.  BAP is a synthetic plant growth hormone.  It stimulates activity from flower spikes, and can produce either flowers or keikis depending on environmental conditions.

Which still does not answer our original question about what conditions make a Phalaenopsis develop a keiki instead of flowers.

The final verdict?

I don't think we actually really know the answer to this question. 

Orchid research is not particularly interested in this question. Commercial growers optimize conditions to produce flowers, not keikis.  And keikis are an inefficient way to reproduce orchids on a commercial scale, leaving little incentive to study keikis when there are important questions to be worked out in meristem cloning and in vitro seed germination techniques. 

If anyone reading this has come across a different claim about phalaenopsis keikis, I'd be happy to look into whether it has a scientific backing.  However, in the meantime, I don't think we know what cocktail of light/temperature/water/nutrients is the Goldilocks recipe to trigger keiki growth.

Monday, December 12, 2016

A crossing of two giants: Rhynvandopsis Memoria Mary Nattrass

Rhynvandopsis Memoria Mary Nattrass (aka Opsistylis)
This orchid is absolutely one of my favorite flowers.  I love the sharp contrast of the patterning on these large waxy flowers. Rhynvandopsis Memoria Mary Nattrass is a primary hybrid between Vandopsis gigantea and Rhynchostylis gigantea, registered in 1972.

Parentage of Rhynvandopsis Memoria Mary Nattrass
Image credits:
Vandopsis gigantea , by Malcolm Manners, Wikimedia Commons image
Rhynchostylis gigantea by Elena Gaillard, Wikimedia Commons image
The parent species are themselves large and showy orchids.  Vandopsis gigantea reportedly has leaves that can reach half a meter in length, while Rhynchostylis gigantea can produce as many as 50 flowers on each inflorescence. 

Interestingly, Rhynchostylis gigantea comes in a great number of variants--the flowers can be white, pink, peach or wine colored, with very different amounts of speckling. This variability translates to Rhynvandopsis Memoria Mary Nattrass as well, which can have different hues and color patterns depending on which variant of Rhynchostylis gigantea was used to generate a given hybrid.

More images of the stunning Rhynvandopsis Memoria Mary Nattrass:

Friday, November 25, 2016

Vanda Roslyn Rogers

Vanda Roslyn Rogers
Vanda Roslyn Rogers is a large pinkish flower, registered in 1990 as a cross between Vanda Fuchs Indigo, and Vanda Yip Sum Wah.  However, unlike the more popular 90's cross Vanda Pachara Delight (which shares 5 out 6 species progenitors in common), this hybrid did not have the same staying power.  Searches for "Vanda Roslyn Rogers" yield few results, most of them referring to people named Roslyn.

The genealogy diagram for Vanda Roslyn Rogers is shown below.  (Link to a larger image view)
Genealogy of Vanda Roslyn Rogers
Just like V. Pachara Delight, the genealogy of V. Roslyn Rogers is dominated by two key Vanda species: Vanda coerulea and Vanda sanderiana. In total, there are 27 crossings depicted in this diagram. V. coerulea provided either the pollen or the seed in 6 of them (22%), and V. sanderiana played a direct part in 13 of the crosses (48%).  

These are the 6 species that contributed to making Vanda Roslyn Rogers.
Species Progenitors of Vanda Roslyn Rogers
Photo credits:
Vanda sanderiana (original image, by Dalton Holland Baptista, Wikimedia commons)
Vanda coerulea (original image, by  Association Auboise d'Orchidophilie Exotique)
Vanda dearei (original image, by Rachmat Setlawan Saleh (Flickr gallery))
Vanda luzonica (original image,  by Akatsuka Orchid Gardens (orchid vendor site)
Vanda tricolor (original image, by Association Auboise d'Orchidophilie Exotique)
Vanda curvifolia (original image, by Association Auboise d'Orchidophilie Exotique)

Personally, I prefer the look of these parent species over the resulting hybrid.  However, it was interesting to see how two relatively similar family trees (Vanda Pachara Delight vs Vanda Roslyn Rogers) produced rather different looking flowers.

Monday, October 24, 2016

A classic blue orchid: Vanda Pachara Delight

Vanda Pachara Delight
Blue is a rare shade among cultivated orchids.  A few wild orchid species achieve that rare hue, but the only true blue cultivated orchid was created by genetic engineering in a Japanese lab in 2013. The gorgeous Phal has since been shown at a number of orchid shows, but don't expect to find one for sale at your favorite nursery any time soon.

In the meantime, Vandas dominate the field of the almost-blue orchid.  Vanda Pachara Delight is one such popular hybrid.  The orchid's flowers are a deep due of purple-blue, although the shade is difficult to photograph accurately.  Registered almost 2 decades ago in 1999, this hybrid is still often found blooming in stores and greenhouses.  Pachara Delight has since been used to make two more hybrids: Vanda Jan Marie Ryan, and Vandachostylis Mak Ho Seng.

Vanda Pachara Delight
Vanda Pachara Delight is a cross between Vanda Gordon Dillon, and Vanda Karulea. The whole genealogy is depicted below. (Full size image)

Genealogy of Vanda Pachara Delight
What stands out the most in this breeding scheme is how prominently Vanda sanderiana features in the genealogy.  There are 22 crossings in this image, and Vanda sanderiana is involved in 50% of them. Vanda coerulea, the second most important contributor to the breeding, accounts for 20% of the crosses. In fact, the primary hybrid of V. sanderiana and V. coerulea (Vanda Rothschildiana) already looks very similar to Vanda Pachara Delight.  
Vanda Rothschildiana (1931)
Photo Credit: Guillaume Paumier (link to original image on Wikimedia commons)

Three other species (V. dearei, V. luzonica, and V. tricolor) contributes to the mix. 
Species progenitors of Vanda Pachara Delight
Photo credits:
Vanda sanderiana (original image, by Dalton Holland Baptista, Wikimedia commons)
Vanda coerulea (original image, by  Association Auboise d'Orchidophilie Exotique)
Vanda dearei (original image, by Rachmat Setlawan Saleh (Flickr gallery))
Vanda luzonica (original image,  by Akatsuka Orchid Gardens (orchid vendor site)
Vanda tricolor (original image, by Association Auboise d'Orchidophilie Exotique)