Byproducts from the agricultural industry and beer have been shown to reduce root-knot nematodes and increase the yields of lettuce crops. Many chemical fumigants have been harmful to human health and the environment and therefore banned from use in agriculture. Researchers have investigated using organic byproducts from farming and beer production to reduce toxic chemicals used and from the agricultural industry as a potential method to disinfest soils. This is for preserving healthy soil microorganisms and increasing crop yields.
In the study published in Frontiers in Sustainable Food Systems, researchers from the Neiker Basque Institute for Agricultural Research and Development in Spain investigated using beer bagasse and agricultural byproducts rapeseed cake and fresh cow manure two organic biodisinfestation treatments. According to the lead author, Maite Gandariasbeitia, “Rapeseed cake and beer bagasse are two potential organic treatments which have shown positive results in previous studies. Their high nitrogen content promotes the activity of beneficial microorganisms in the soil, which helps to break down organic matter like manure and kill off nematodes and other parasites which damage crops.”
Maite also highlights how crop yields can be negatively impacted. “Root-knot nematodes are a type of common soil parasite which penetrate a plant’s root tissue to lay their eggs, and this activity causes galls, or knot-like swellings, to form on the root,” she says. This damage negatively impacts root development, and this means crops can’t take up nutrients efficiently, slower plant growth, and reducing yields for farmers.
To reduce these nematode populations and disinfect the soil, rapeseed cake and beer bagasse were incorporated into the soil and fresh cow manure as a potential organic treatment. The researchers found after the first crop post-treatment a significant reduction in galling on plant roots. Increased yields by around 15% plots also demonstrated compared to the control plots after one year. The organic matter treatment boosted the population of beneficial microorganisms in the soils.