C. walkeriana (not) ‘Kenny’

[Anglo]

The plant patent for Cattleya walkeriana ‘Kenny,’ issued to Limrick.RTM Orchid Nursery in June 1994, states that it is the result of a cross between Cattleya walkeriana ‘Pendentive’ var. alba (pod parent) and Cattleya walkeriana ’Hunabu.RTM’ var. semi-alba. I don’t know anything about the pollen parent, but ‘Pendentive’ is really a C. dolosa. It originated from a selfing of C. walkeriana ‘Orchidglade.’ Orchidglade’ is an apparent natural hybrid that was found in the wild. It’s called a walkeriana and its flower looks like C. walkeriana, but its pseudobulbs tend to be somewhat elongated. Some argue that ‘Orchidglade’ is a pure walkeriana, but I don’t see how it could be if ‘Pendentive’ resulted from a selfing of it.

In 2009, the American Orchid Society’s Species Identification Task Force concluded that ‘Kenny’ is a hybrid, and appears to be C. Snow Blind (C. Angelwalker x C. walkeriana var. alba ‘Pendentive’). I don’t know how they arrived at Snow Blind, particularly since 'Pendentive' is now known as a hybrid, but as you can see from the list of hybrids below, they are all combinations of walkeriana and loddigesii. The difference between C. dolosa and the others is that C. dolosa originated naturally. It is categorized as a species because it is genetically stable and reproduces in uniform populations.

C. dolosa - C. loddigesii x C. walkeriana; natural hybrid
C. Heathii - C. loddigesii x C. walkeriana; artificial hybrid
C. Obrieniana - C. loddigesii x C. dolosa
C. Little Angel - C. loddigesii x C. Obrieniana
C. Angelwalker - C. Little Angel x C. walkeriana
C. Snow Blind - C. Angelwalker x C. walkeriana

I’ve been interested in walkeriana-loddigesii hybrids for a long time. I decided to pick up this ‘Kenny’ mericlone awhile back for personal observation. The real confirmation for me that ‘Kenny’ is not a walkeriana is its fragrance. It has a dolosa fragrance with no detectable trace of the walkeriana scent.

[Royal]

So you're saying that walkeriana 'Orchidglade' is really C. xdolosa? Making 'Pendendtive' the same as it resulted from selfing 'Orchidglade'? If that's the case, acourding to the patent, 'Kenny' would really be xdolosa x walkeriana, making it a C. Tsiku Taiwan.

[Anglo]

Yes, it would be a C. Tsiku Taiwan, provided that Cattleya walkeriana ’Hunabu.RTM’ is a pure walkeriana. C. Tsiku Taiwan should have been included in the list above.

[isurus79]

It looks great, whatever it is! Too bad about the scent though. Walkeriana scent is phenomenal.

[Mathias]

There is a Japanese study that indicated that C. walkeriana var alba 'Pendentive' probably is a true walkeriana. See link to english abstract:

Science Links Japan | Randomly Amplified Polymorphic DNA Analysis for Establishing Phylogenetic Relationship among Cattleya walkeriana Gardn., Cattleya nobilior Rchb.f. and Cattleya loddigesii Lindl.

Article in Japansese (some can be understood):

http://ci.nii.ac.jp/naid/110001803562/en

[Aceetobe]

Its kind of unfair to say that its really walkeriana based on that paper. They show that it forms a cluster with other alba walkeriana's - namely - 'Orchidglade' and its decendents!

Phylogenetically, it looks like based on the data that all of the albas are closer to Angelwalker than tipo walkeriana!

[trdyl]

Originally Posted by Mathias

There is a Japanese study that indicated that C. walkeriana var alba 'Pendentive' probably is a true walkeriana. See link to english abstract:

Science Links Japan | Randomly Amplified Polymorphic DNA Analysis for Establishing Phylogenetic Relationship among Cattleya walkeriana Gardn., Cattleya nobilior Rchb.f. and Cattleya loddigesii Lindl.

Article in Japansese (some can be understood):

CiNii- Randomly Amplified Polymorphic DNA Analysis for Establishing Phylogenetic Relationship among Cattleya walkeriana Gardn., Cattleya nobilior Rchb. f. and Cattleya loddigesii Lindl.

Welcome to OB!

Thanks for the links. It is good to see that ‘Pendentive’ is being supported as a true Cattleya walkeriana alba. I wonder how the rest of the orchid world is going to react to the study.

[Mathias]

Thank you Ted!

@ Acetobee: I am no expert in phylogenies but I think that Angelwalker should be considered an "outgroup" for all walkerianas based on the structure of that phylogenetic tree. That Angelwalker is located directly below the albas should not matter, only how it is linked. But I may be wrong...

[catwalker808]

If you only read the abstract (the brief summary which is in English) of the Japanese DNA study, it is easily to interpret it as saying that the DNA testing indicates Pendentive is a true walkeriana. As important as what IS said in the abstract is what is NOT said. The abstract states that DNA analysis indicates that C. nobilior and C. walkeriana fall into separate clusters and are definitely separate species. The abstract goes on to state that the plants labeled as C. walkeriana (including one plant, ‘Pendentive’, which is questioned as being true C. walkeriana) were separated into two other clusters. One cluster consisted of the majority of the C. walkeriana samples. The second “C. walkeriana” cluster consisted of ‘Pendentive’ and two other white flowered “C. walkeriana” samples. Because of this clustering of ‘Pendentive’ and two other plants presumed to be C. walkeriana, reading only the abstract can lead to the conclusion that ‘Pendentive’ is indeed a true C. walkeriana.

However, the fact that there were two separate clusters of purported C. walkeriana bothered me. Why two clusters … even though the abstract indicated that flower color was one determinant for the second cluster? However, the full report sheds some light on a more probable reason for the grouping of ‘Pendentive’ and the two other plants into a separate cluster. Absent from the abstract, but contained in the full report, is an important detail: the two other plants grouped with ‘Pendentive’ in the second “C. walkeriana” cluster were ‘Orchidglade’ and ‘Perfect Charm’.

‘Orchidglade’ is the parent of ‘Pendentive’. ‘Perfect Charm’ is the offspring of ‘Orchidglade’, and, if not a sibling of ‘Pendentive’, then at least a half-brother. It is, therefore, entirely logical that the three plants are grouped together in a separate cluster. They are first generation direct relatives.

The research report indicates that the samples, used in the analyses, were provided by an individual or group of orchid growers in Japan. Presumably, the research was requested to answer several questions: one being whether C. nobilior and C. walkeriana are distinct species; another being whether ‘Pendentive’ is a true C. walkeriana. Throughout Japan and among many C walkeriana enthusiasts, ‘Pendentive’ is not considered to be a pure C. walkeriana. Several aspects bothered me about the abstract and what I could decipher from the full report (written in Japanese). For more than six months, I had attempted to find out who had provided the plants and requested the research.

Two days ago, while here in Japan, a Japanese C. walkeriana grower (who is also an orchid judge), who I have known for more than 7 years, approached me to discuss a collaborative effort to write a tri-lingual article on C. walkeriana. We spoke for nearly an hour discussing our respective roles in writing the article. During this discussion, I happened to ask him if he knew about the Gifu University DNA study and also who had provided the plants for the study. He told me that he had provided the plants and had requested the study. What a great chance discovery! We then discussed the research findings for another hour or more.

Apparently, he also had been perplexed about the two “C. walkeriana” clusters reported in the study. Not surprisingly, while expert in DNA research, the researcher was not an expert concerning C. walkeriana. Without knowing the first generation relationship between the ‘Orchidglade’, ‘Pendentive’ and ‘Perfect Charm’, one could easily conclude that by association, ‘Pendentive’ was also a C. walkeriana. On the other hand, since these three plants are close relatives, their DNA clustering is to be expected and does little to prove that ‘Pendentive’ is a true C. walkeriana. They are clustered together because they are close “blood relatives”.

And the fact that, these three closely related plants, are in a cluster separate from the known cluster of C. walkeriana only makes them more suspect of not being pure C. walkeriana.

The DNA research also involved analysis of C. loddigesii and C. dolosa (C. loddigesii being the suspected other species in the ‘Pendentive’ bloodline). My acquaintance noted that apparently, the DNA of the ‘Pendentive’ cluster may resemble the C. dolosa DNA as closely as it does the DNA of the larger cluster of C. walkeriana … an aberration, if ‘Pendentive’ is presumed to be C. walkeriana, but entirely logical if ‘Pendentive is C. dolosa or part C. loddigesii. My Japanese friend promised me a copy of the complete study, as well as an English translation.

The basic reason for the controversy concerning ‘Pendentive’ being a true C. walkeriana stems from over two decades of observations by many people expert in C. walkeriana. The differences concerning ‘Pendentive’ are not insignificant. First, the basic plant form differs greatly from C. walkeriana plants.
The original 2N form of ‘Pendentive’ has very slender elongated pseudobulbs, compared to the squat rounded pseudobulbs of C. walkeriana (even when compared to heavily fertilized C. walkeriana plants). ‘Pendentive’ has been mericloned many times and many mutant 4N tetraploids have resulted. Of course, these superior, rounder flowers on stockier plants have been chosen for breeding or further mericloning. As a result, many, if not most, hobbyists today perceive these stockier 4N ‘Pendentive’ plants as resembling C. walkeriana.

In addition, by becoming rounder and more compact, the 4N flower has disguised some of the more prominent features of the original 2N ‘Pendentive’, attributed to C. dolosa or C. loddigesii. For example, the transitional section between side lobes and lip of ‘Pendentive’ and its crosses have a very noticeable ruffling, as on C. loddigesii flowers (which has been somewhat truncated in 4N ‘Pendentives’), whereas, this section on C. walkeriana flowers is normally smooth.

What has not been disguised is ‘Pendentive’s habit of blooming from the leaf axils of regular pseudobulbs, rather than from specialized flower growths which emerge from the base of pseudobulbs on true C. walkeriana plants. On rare occasions, C. walkeriana plants may produce flowers from leaf axils, especially if the growth cycle is somehow altered or interrupted. In contrast, ‘Pendentive’ blooms regularly from leaf axils. When ‘Pendentive has been crossed back to C. walkeriana, the increased proportion of C. walkeriana in the crosses have resulted in a somewhat diminished tendency to blooming from leaf axils.

There are other observable differences, however, these are a few of the most distinct ones. I was not aware of the difference in fragrance in ‘Pendentive’ flowers, but I would not doubt it. Last week, I had nearly 30 C. walkeriana blooming in my hotel room here. The room was filled with such a refreshing clean light scent, that the girl delivering our luggage remarked on the fragrance.

In graduate school, we sometimes derided trivial academic arguments as debating over how many angels would fit on the head of a pin. However, the issue of whether ‘Pendentive’ is a true C. walkeriana is very important to serious collectors and hybridizers of C. walkeriana. Essentially, a blind bee, guided only by his sense of smell, could pollinate ‘Pendentive’ and produce a round flowered HYBRID … but it would not be C. walkeriana. In contrast, it requires significant experience, expertise and superior C. walkeriana parent plants to produce superior quality true C. walkeriana flower forms.

I apologize for this lengthy response concerning ‘Pendentive’. However, it does relate to ‘Pendentive’s’ various offspring and relatives and is an important issue for those of us who have invested so much time and effort into serious C. walkeriana breeding.

[trdyl]

catwalker808, Thank you for the explaination.