INFLUENCE OF RYE (SECALE-CEREALE) PLANT RESIDUES ON GERMINATION AND GROWTH OF 3 TRIAZINE-RESISTANT AND SUSCEPTIBLE WEEDS

Greenhouse and laboratory studies were conducted to evaluate the effec ts of rye residues on germination and growth of three triazine-resista nt weed species, barnyardgrass, willowherb, and horseweed. Soil contai ning rye roots was used to determine rye residue influence on seed ger mination. Willowherb and horseweed germination was inhibited up to 50% with the highest rate of rye, but there was no inhibition of barnyard grass germination. Aqueous extracts of rye shoot tissue inhibited incu bator germination of horseweed and willowherb, but did not significant ly influence barnyardgrass germination. Although there were no germina tion differences between the susceptible and resistant biotypes, both were totally inhibited when a 5% w/v solution was used. Growth inhibit ion of the selected weeds was evaluated using rye root residues in soi l. All combinations of biotypes, species, and rye seeding rates showed significant growth inhibition.