MATERNAL EFFECTS IN PROGENY OF FIELD PANSY (VIOLA-ARVENSIS) SUBJECTEDTO DIFFERENT HERBICIDE AND NITROGEN RATES

Observations were made on the effects of reduced rates of herbicide an d nitrogen on naturally occurring populations of Viola alvensis. Proge ny arising from these plants were grown in a uniform environment and m onitored through to maturity. The size and number of reproductive stru ctures produced by the maternal plants were positively correlated with the maternal plant weight. Herbicide dose affected the plant height o f offspring and the effects were more pronounced in those from plants which had received 160 kg N ha(-1) than 40 kg N ha(-1). Although the m aternal effects on offspring size diminished with time, the number of reproductive structures in the offspring was significantly correlated with plant height during early development. Increased nitrogen availab ility to the maternal plant in the absence of herbicide may therefore increase the overall productivity of the subsequent generation.