Destruction of the ovules/seeds
Ovules and seeds of pollinated and developing ovaries
on intact plants were killed at different times after anthesis
(Fig. 1) by piercing thetB with a thin (0.1 mm
diameter) copper wire. This operation was facilitated by
laying the ovaries against a light box and using a magnifying
glass when necessary. Fruits in which any ovule
had developed by the end of the experiment were discarded.
Controls were carried out by pricking the pods
with the wire but without damaging the ovules.