The implications of reduced doses of fluroxypyr and wheat cultivar choice on the seed production, growth and development of the progeny of common field speedwell.

Abstract

Reduced doses of herbicides are now widely being used in cereal crops with little yield penalty. Studies of weeds in these conditions have largely been restricted to the effect of herbicides on weed biomass and hence the weed infestation in the current year. This study was designed to investigate the combined effect of wheat varietal selection and herbicide dose on weed seed production and some qualitative aspects. The largest effect on quality was an alteration in the relative proportions of individual seed size. Herbicide applications increased the proportions of smaller sized seeds at the expense of the larger seeds. Progeny from these seeds showed indirect herbicide effects related to the size of seed from which the plants originated. Implications for future weed infestation are considered.