Not so plain vanilla

Speaking of vanilla, as I was elsewhere … A very odd story caught my eye.

Bronze Age people in Israel were the first known vanilla users

Obvious clickbait, right. I mean, vanilla came originally from Mexico, as any fule kno. The photo, of highly ordinary vanilla pods in a very modern plastic basket confirmed my suspicions. The caption:

Although long considered a product that originated in ancient Mexico, vanilla — which is extracted from beans such as these — was used by Middle Easterners around 3,600 years ago, a new study finds.

Well dodgy, but not exactly wrong. Not exactly.

My first thought was that maybe the archaeologists had fooled themselves. After all, pure vanillin is a byproduct of the degeneration of lignin. Maybe a bit of decomposing wood contaminated the juglets in which the stuff was found. But no. The truth is even more interesting, and hidden deep in Science News’ account.

For a start, the juglets also contained traces of olive oil. And while plain vanilla usually signifies the species Vanilla planifolia, there are, in fact more than 100 different species around the world. Vanessa Linares, the archaeologist who identified the compounds, refers to “the vanilla orchid” in an abstract of her research. In fact, she compared the compounds she found with those produced by other species of Vanilla, and suggests that it could have come from one of three different species.

After a close study of vanilla orchid plants, three different species were identified as possible sources for vanilla exploitation in antiquity: V. polylepsis [sic] Summerh (central east Africa), V. albidia Blume (India), and V. abundiflora J.J. Sm. (southeast Asia).

I think, under the circumstances, I might have written “a vanilla orchid”.

Anyway, parsimony suggests (to me) it was V. polylepis from east Africa which, although apparently showy and widespread, was not described formally until 1951. If it did travel from east Africa to the Levant, that is impressive enough. Even more so is that the people who traded it 4000 years ago knew how to undertake the painstaking fermentation that is the secret to the odour and flavour of natural vanilla. The pods barely smell, and certainly not of vanilla.

So yes, not quite what Science News was trying to sell, but pretty interesting all the same. And a project for some enterprising breeder in east Africa: Domesticate your local vanilla.

PGR in academia

European Seed is a new(ish) magazine aimed at the European seed sector. Its latest issue features a discussion about what academic institutions have to do to access and make available plant genetic resources according to all the relevant rules and regulations. Among the various experts involved in the Q&A is Theo van Hintum, of the Dutch genebank, well known to our blog.1 Here’s a snippet.

Footnotes:
  1. I learnt about it through a tweet from CGN. []

How to do seed longevity experiments

The article “Seed longevity phenotyping: recommendations on research methodology,” by Fiona Hay and others, is now freely available online. Read the whole thing, and note the use of DOIs, if you’re thinking of phenotyping seedlots for longevity or storability. But here’s the bottom line, just to whet you appetite:

  • Use ageing conditions that are appropriate to the potential downstream use of the findings. Ideally such conditions should be standardized to enable comparisons across studies and perhaps, species.
  • Take enough samples for germination testing such that a survival curve can be fitted to the data and appropriate parameters determined.
  • Specify if seeds were de- or adsorbing moisture; determine the MC of the seeds if they are placed in a controlled-RH environment (e.g. over a saturated salt solution).

In an earlier Brainfood I said it was behind a paywall, which I swear it was when I checked, but that’s not the case anymore, thank goodness.

An experiment on cassava degeneration, Twitter-style

IITA plant virologist James Legg asks:

Cassava mosaic virus disease & Cassava brown streak virus disease constrain production throughout East & Central Africa, but do the effects get worse if farmers keep recycling planting material?

Yes, right?

Well, it’s more complicated than that. Spoiler alert:

1. Degeneration is most clear in resistant varieties as it happens slowly
2. Virus-free planting material gives greater yield gains than extreme resistance
3. BUT, virus-free material has no value for highly susceptible varieties

But read how they got there.

Brainfood: Makapuno, Middle Eastern dogs, Date palm origins, Speedy NUS, Red apples, Apple characterization, Phenotyping double, Assisted migration & pathology, Soya diversity, Sustainable intensification, Seed research, Cucurbita history, Potato value chains, Livestock ES