Use of organic residues in biodisinfection soil processes for the biological control of plant pathogens
The ban of chemical fumigants, such as halogenated hydrocarbons, on intensive agricultural production, has led to a increasing interest in new methods of biological control of soil-borne plant pathogens. One of the most promising methodologies is the biodesinfección consisting in the introduction of organic residues into soil solarization processes, whose decomposition produces gases with fumigant effect and contributes to restore soil health for later crops
The substitution of chemical fumigants such as methyl bromide and other halogenated hydrocarbons, has been done looking for alternative new products with a similar effect such as as metam sodium or dazomet, products whose hydrolysis produces volatile isothiocyanates, but all of them facing increasing legal restrictions due to their toxicological and environmental problems. Alternatively, different processes have been used as so-called biological biofumigación, in which plants residues of Brassicas also produce isothiocyanates in their decomposition due to their high glucosinolate content. The objective is to generalize these processes using local wastes generated in agricultural or agro-industrial activity optimizing their use as soil biodisinfectants.
Laboratory and field experiences done by the research group UBUCOMP show that it is possible to obtain this biofumigant effect through the anaerobic decomposition of an adecuate mixture of organic wastes of agricultural origin as manure, crop residues, vinasses, molasses, alpechin, spent mushrooms, seaweed, lignosulfonates, etc. in what is generically called soil biodisinfection. Performing the process simultanously with solarization processes, in which the soil is sealed and its temperature increased, it has been shown as an effective method to control phytopathogenic fungi and nematodes
Soil biodisinfection technique is being increasingly used due to current legal restrictions on the use of chemical fumigants and the need for lower toxicological and environmental impact alternatives. At the same time a valorization of the organic residue is achieved, pollution problems due to its high biodegradability are avoided, the overall process leaves no toxic residues in the soil and is compatible with organic agriculture. At the same time, soil biological activity is activated, improving soil health and the resistance to pests and plant diseases.
This technique is of interest to farmers involved in intensive agriculture into greenhouses, intensive horticulture, organic agriculture, cultivation of strawberry, sugarbeet, corn or potato crops, in which there is an important incidence of plant parasitic nematodes. Also for organic waste producers to generate soil amendments with biodisinfectant properties.
COMPOSTING RESEARCH GROUP
Jose Manuel López López
+34 947 25 8895