Late last year, a large number of proposals for fundamental research within the top sector horticulture and starting materials were submitted to the Dutch Institute for Scientific Research (NWO Green call). The proposal of Martijn Bezemer of Netherlands Institute of Ecology (NIOO) with Wageningen UR Greenhouse Horticulture for resilient chrysanthemums was approved.
Previous research has shown that plants are able to condition the soil and that a successive crop can benefit from this. An example from the work of Bezemer (wild plant species) is Tansy that gives a suppressive effect on aphids in a subsequent culture with ragwort.
Chrysanthemum is the most important cut flower crop in the greenhouse in the Netherlands. Aboveground and soil-borne diseases and pests are a major problem in this crop. Examples include trips, Pythium and nematodes. To reduce disease outbreaks, soil is regularly sterilized by soil steaming. Inoculation of sterilized soil with communities of soil microorganisms can increase resistance to soil diseases. Through their influence on the chemistry of the plant, they can also affect aboveground assailants.
In this new project, it is investigated how inoculating sterilized soils with microbial communities, which are known to increase resilience of chrysanthemum against soil diseases, affects the susceptibility to aboveground insects. It also examines how the inoculation of the soil affects the natural enemies of pests and overhead so the biological control of these pests.
The ultimate goal of this research is to develop soil inocula that can be used to increase resilience of cut flowers of both underground-, and above-ground pests and diseases.
This project is implemented by the Netherlands Institute of Ecology (NIOO) together with Wageningen UR Greenhouse Horticulture and supported by the biocontrol company Biobest and the national committee of chrysanthemum growers.