Allelopathy relationship between plants and their use in organic farming

Abstract

Allelopathy is a process still little studied in the plant world, if we refer to the diversity of biochemical compounds, through which plants can interact with each other, with fungi or bacteria. Biochemical "dialogue" between organisms may have stimulatory or inhibitory effects, contributing to numerical setting of the populations, the assertion of some species over others, the establishment and strengthen of plant communities. Practically, the allelopathy can be exploited in organic farming in understanding and identifying compatibility between species, to finding natural substances with herbicide potential. In experiments conducted, diluted extracts of Taraxacum officinale and Cirsium vulgare strongly inhibited the germination and growth of corn and beans, while Hedera helix produced the same effect, but at higher concentrations of the extract. Humulus lupulus extract has a stimulating effect on the two species and it is possible to use as natural fertilizer. Extracts of Chenopodium album works as stimulator for Beta vulgaris, and potent inhibitor for Triticum aestivum. Agropyron repens is an aggressive competitor for Lycopersicon esculentum and Capsicum annuum, producing a strong inhibition. Juglans regia extracts and especially those of Satureja hortensis, can be used as natural herbicides for up delay germination and growth suppression for the species: Echinochloa crus-galli and Setaria glauca.