RE: # of locules as determining factor was RE: [tomato] Funky Looking Tomatoes (
Wed, 11 Aug 1999 20:49:19 -0400

Thanks for your erudite reply. For the benefit of the uninitiated, such as
what is a locule, please?

You're right....I was guilty of making-the-simple-complicated and using a
nickel word when a penny one would work. Apologies.

Botonanists classify the tomato fruit as a berry. "Locule" refers to the
ovary and the number of divisions of this berry's compound ovary are what
determines whether a tomato is a cherry, beefsteak, etc. type.

Seeing is easier than trying to explain locules, so grab a tomato and a
knife: Cut a paste/plum tomato open (lengthwise or crosswise, makes no
difference) and you'll see the structure: two locules. A cross section of a
beefsteak will show six or more locules. The seeds are contained within the
individual locules.

The original tomato was a two-locule berry (and the locule was very small
compared with most of today's varieties). Increase both locule size and
number is one of the most interesting areas to ponder when you start trying
to figure out why/how so many thousands of varieties have developed.
Recessive mutation is part of the various modifying genes that
have "shown up" over time to give us the richness of variety available

Catharine (and don't forget to gobble up the tomato after using it in the
experiment <grin>)