Effects of 2,4-D on Seed Production and Embryo Development of Curly Dock

Abstract

Lithium salt of (2,4-dichlorophenoxy)acetic acid (2,4-D) (1000 ppm) was sprayed on plants of curly dock (Rumex crispus L.) 12 days before anthesis, at an thesis, 7 days after anthesis, and 34 days after anthesis. Treatment 12 days before anthesis completely prevented the formation of viable seeds. Two percent of the seeds had minute embryos after treatment at anthesis, but even these seeds did not germinate. Embryos were present in 91% of the seeds from plants treated 7 days after anthesis. These embryos ranged in size from 0.5 to 2.5 mm. The total weight of seeds obtained was significantly less than the control and only 5 to 15% of these seeds were capable of germination. Spraying the inflorescences 34 days after anthesis did not affect the number of seeds produced or seed viability. Almost all plants remained alive after the harvest.