Effects of phenolic acids on seed germination and seedling growth in soil

摘要

It is commonly assumed that the adverse effect of plant residues on crop yields is largely or partly due to phytotoxic compounds leached from these residues or produced by their decomposition. There has been substantial support for the hypothesis that the phytotoxic compounds responsible for reduced crop yields are phenolic acids such asp-coumaric acid,p-hydroxybenzoic acid, and ferulic acid. To test the validity of this hypothesis, we studied the effects of nine phenolic acids (caffeic acid, chlorogenic acid,p-coumaric acid, ellagic acid, ferulic acid, gallic acid,p-hydroxybenzoic acid, syringic acid, and vanillic acid) on (1) seed germination of corn (Zea maysL.), barley (Hordeum vulgareL.), oats (Avena sativaL.), rye (Secale cerealeL.), sorghum Sorghum bicolor(L.) Moench, wheat (Triticum aestivumL.), and alfalfa (Medicago sativaL.) on germination paper and soil, (2) seedling growth of alfalfa, oats, sorghum, and wheat on germination paper and soil, and (3) early plant growth of corn, barley, oats, rye, sorghum, and wheat in soil. The results showed that although the phenolic acids tested affected germination and seedling growth on germination paper, they had no effect on seed germination, seedling growth, or early plant growth in soil even when the amounts applied were much greater than the amounts detected in soil. We conclude that the adverse effect of plant residues on crop yields is not due to phenolic acids derived from these residues.