Case Study 4. Use of mycorrhiza in potato fields to reduce the incidence of common scab, decrease the use of phosphorus fertilizers, increase the crop yields and increase the soil biodiversity. Lusitanean (Spain)
Which problem will be solved: The potatoes cultivation must be performed in very acid conditions (pH <5.0) to avoid the common scab disease due to the high organic matter contents in the soils. Under these conditions, P availability is very low and despite the presence of high amounts of phosphorus in the soils, the farmers in the area use big amounts of P fertilizers annually. Also in very acid soils the diversity of microorganisms and soil fauna is generally low. The common scab caused bad appearance in potatoes, and hence they can be only used for industrial uses, not for direct commercialization, decreasing the potatoes value.
State of the art: The use of mycorrhiza associated to potatoes cultivation in the area was negligible and research on native mycorrhiza to be used for potatoes production increases and protection against diseases was not performed yet.
Objective: The objective of this case study is to reduce the common scab incidence in potatoes crops, decrease P fertilization, allow potatoes cultivation at higher pH, and hence increase the crops yields and soil biodiversity.
Proposed management practices: We will introduce mycorrhiza associated to potatoes crop to plant protection against common scab and increase P uptake by plants. Also we will perform soil sampling and establish the trap cultures to isolate the native AMF species from the target field sites.
Progress with the case study in relation with the state of the art: An adequate potatoes colonization by mycorrhiza will protect crops against common scab, provide a better P nutrition, and allow cultivation at higher soil pH. Therefore, production and value will increased, P inputs decreased and soil biodiversity increased.