Oh Raphanus sativus, why are you red?

In the past couple years I have picked up a radish habit.  I get some fresh radishes, wash, scrub and dry them and eat them with butter and salt.  In the process of preparing the radishes I wonder about their bright red color, and the fact that when immersed in water, a purple color results in the water.

What actually caused the red in a radish?  Here's the answer:

There are some very interesting pigments in radishes.  The pigments are called anthocyanins and there are four main types in red radishes.

Two novel diacylated anthocyanins, 
1) pelargonidin 3-O-[2-O-(β-glucopyranosyl)-6-O-(trans-p-coumaroyl)-β-glucopyranoside] 5-O-(6-O-malonyl-β-glucopyranoside) and 
2) pelargonidin 3-O-[2-O-(β-glucopyranosyl)-6-O-(trans-feruloyl)-β-glucopyranoside] 5-O-(6-O-malonyl-β-glucopyranoside), were characterized. 


Two other monoacylated anthocyanins were determined to be 


3) pelargonidin 3-O-[2-O-(β-glucopyranosyl)-6-O-(trans-p-coumaroyl)-β-d-glucopyranoside] 5-O-(β-glucopyranoside) and 


4)  pelargonidin 3-O-[2-O-(β-glucopyranosyl)-6-O-(trans-feruloyl)-β-glucopyranoside] 5-O-(β-glucopyranoside). 


I think we may need a few organic and biochemistry reviews in order to appreciate what we have here.  The link to a useful paper is here:


http://pubs.acs.org/doi/abs/10.1021/jf980695b

But, I am assuming most of you won't have access to the full text, so let's take a different tack.  The name of the compound, pelaronidin is very interesting. Let's find out more:

https://wiki.ch.ic.ac.uk/wiki/index.php?title=It:Pelargonidin

Aha, it is a flavonoid, and these compounds enrich our lives by providing many of the beautiful, bright colors we see in the natural world.  It seems our pelargonidin provides the colors in strawberries, red geraniums and raspberries.

Fascinating!

Weird dandelions

I'd like to start out this blog with something I observed on our front lawn. Dandelions are regarded by many as the bane of suburban existence but I've really had a neutral attitude to them for the most part. As a science educator when I see them pop up I immediately think of how great they would be for an activity on seed dispersal.

This year I've been watching them more closely as I am determined to try and get the yard in better shape. Here's the story...

Last weekend I mowed the lawn for the first time. I used a new-fangled electric mower and the blade isn't quite powerful enough to take care of many so-called weeds, dandelions in particular. Last week the golden yellow little fellows were evenly distributed over most of the lawn. By the way, I have stopped using chemical fertilizers and weed killers so the lawn is definitely an exercise in plant diversity. I finished mowing the lawn and the next morning I opened the front door and what did I see? Hundreds of slender tubes that seemed to pop up overnight. During the week they came up slowly, and as I look back on it, they almost seemed to be waiting.

Yesterday, we had a nice mild, sunny spring day and I noticed all of the dandelions had full fluffy heads of seeds and that they had shot up to quite astonishing heights. This morning I woke up and heard strong winds outside, it is a very, very windy day. When I was at the dry cleaners, my clean shirt on a hangar, enveloped in plastic, took off like a shot as wind whipped through the door the establishment.

Anyway, here is what I wonder. Was it just a coincidence that the dandelions grew to maximum height and had their seeds ready right before a very windy day? Can plants detect environmental stimuli indicating a windy day is coming up, and then make rapid growth to take maximum advantage of an opportunity to disperse seeds?

In any event, I think it might be very interesting to do a study of dandelion reproduction in the wild, and in controlled experiments.