[Prev][Next][Index][Thread]

Nigthmare? in the Tilling Fields



Dear Carol,

This idea of using dark cultivations to control weeds which are stimulated by 
light into germination is not a new one. Hartmann and Nezdal (1990) 
Naturwissenschaften 77, 158-163 reported very similar results to those you 
describe from the USDA author.
The idea is based on the principal that the phytochrome system, which is 
responsible for many germination responses, will not be stimulated if 
cultivations are completed in the dark because of the absence of red light.
There is a possible problem with the idea though. There are several weedy 
species which produce seeds which do not require  red light in order to 
germinate. If dark cultivations were employed for any length of time the 
tendancy would be select for those species and populations and you could end up 
with a worse weed problem than you started with!

Geoff Seavers
IACR-Long Ashton
Long Ashton
Bristol
BS18 9AF
UK