Biomass from Allelopathic Agroforestry and Invasive Plant Species as Soil Amendments for Weed Control—A Review

• Published in: Agronomy (Basel) Vol. 13; no. 12; p. 2880
• Main Authors: Valiño, Antía, Pardo-Muras, María, Puig, Carolina G., López-Periago, J. Eugenio, Pedrol, Nuria
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-12-2023
• Subjects: Agricultural practices; Agriculture; Agroforestry; Allelochemicals; allelopathic biomass; Allelopathy; Biological products; Biomass; Cover crops; Crops; DNSH; Ecosystem services; Ecosystems; Essences and essential oils industry; Essential oils; Fertilizers; Flowers & plants; Germination; green manure; Herbicide resistance; Herbicides; Introduced species; Invasive plants; Invasive species; IWM; Manures; Metabolites; Microorganisms; Nonnative species; Oils & fats; Pesticides; Phytotoxicity; Plant extracts; Plant species; plant-based approaches; Plants (botany); Residues; Soil amendment; Soil amendments; Soils; Toxicity; VOCs; Volatile organic compounds; Weed control; Weeds; South America; Spain
• ISSN: 2073-4395; 2073-4395
• DOI: 10.3390/agronomy13122880

Effective weed management faces increasing legislative restrictions for the use of herbicides due to their toxicity and environmental persistence. In addition, the linear increase in resistant weeds threatens to render authorized herbicides useless. In a post-herbicide era, under the IWM strategy, allelopathy can play a relevant role since many plants can produce a variety of allelochemicals with different structures and modes of action, capable of inhibiting the germination and growth of different weed species. Inspired by green manuring with cover crops, the use of allelopathic biomass from weeds, invasive species, residues of forestry plantations, and other abundant wild plants has some advantages over green manures grown in situ or other alternatives such as applying plant extracts or essential oils. Beyond the ecosystem services provided by green manures, the potential use of allelopathic biomass offers extra opportunities for the science and practice of holistically integrated weed management because (i) the investment of resources and time for producing cover crops would be alleviated, and (ii), new use of agroforestry residues and a sink for harmful weed biomass is provided. In this review, we compile the current knowledge of those allelopathic species whose biomass, used as soil amendment, effectively controlled weeds. In addition, the complex allelopathic processes underlying the effectiveness of cover crops and allelopathic biomass used as green manures for weed control are revisited.