In the search for alternatives to chemical soil disinfection, biological control agents (BCAs) have been tested in the soil, so far without success.
"It is still unclear why we have not observed any effectiveness of the BCAs in any of the trials. Studies in the literature indicate that beneficial effects of these BCAs can be found, but they are mostly conducted in substrates. It is clear, however, that the results cannot be directly transferred to crops in open fields," the researchers conclude after completing the VLAIO project ALTCHEM.
The existing microbiome and the physicochemical properties of the soil are likely to play a significant role in how these introduced microorganisms can develop in the soil, the researchers state, emphasizing the need for further studies to demonstrate the added value of BCAs in field cultivation.
Soil pests
Inagro researchers have also worked on developing monitoring techniques for BCOs in soil. The research has been conducted in head lettuce, lamb's lettuce and in ground chicory for Rhizoctonia solani (black rot) in head lettuce, Pythium sylvaticum (yellowing disease) in lamb's lettuce and in ground chicory against Sclerotinia sclerotiorum (rat's throat disease).
In addition, the field trials also looked at the effect on naturally occurring pathogens such as Botrytis cinerea (grey mould), Phytophthora cryptogea (brown penrot), and Fusarium oxysporum f.sp. lactucae (Fol) (processing disease).
Read more about the study and exactly how it was conducted at Inagro.