The current market is forcing growers of leafy vegetables under glass to strongly establish cost efficiency, so they have to specialize in one Tee's. The year-round growing a monoculture (butterhead lettuce / lamb's lettuce), however, poses problems with soil pests and diseases related with them. The major land-based greenhouse pathogens in the cultivation of leafy vegetables are Pythium spp, Sclerotinia spp, Rhizoctonia solani and Botrytis cinerea, which all cause a similar clinical picture:.. Rotting of the lower leaves that touch the ground (taint). In the nematode is clear from reports in the practical centers, and a screening was carried out in 2014 in 30 Flemish slaserres an increasing presence of Pratylenchus penetrans and Paratylenchus sp .. fungicides are currently being deployed against the blemish pathogens via foliar treatments. Scleroten against fungi and nematodes is being appealed to chemical fumigants. In essence, the problem is that often can not be optimum use of available resources. That leads to a more than necessary use of chemical pesticides with adverse effects on beneficial soil life, which suppresses the growth of stain pathogens and harmful nematodes.