Controlled Atmosphere Temperature Treatment as Sustainable Alternative to Control Strawberry Tarsenomid Mites and Plant Parasitic Nematodes in Strawberry Plants

High qualified strawberry (Fragaria × ananassa) planting material, mainly for export, is produced by Dutch growers on circa 1100 ha field area in The Netherlands. Planting stock must be destroyed if strawberry tarsonemid mite (Phytonemus pallidus) or infection by the plant parasitic nematode Meloidogyne hapla is found by the Dutch Quality Board. Also the nematode Pratylenchus penetrans can attack strawberry plants severely. The presence of tarsonemid mites in plant material can result in a considerable loss of production. Until 2007 in The Netherlands mother planting stock for runner production was treated with methyl bromide (MeBr) to eliminate tarsonemids. This chemical disinfestation method is banned since 2008. From 2007 the choice was made to optimize the Controlled Atmosphere Temperature Treatment (CATT) to provide a non-chemical and sustainable method for future disinfestation. By application of CATT during 48 h at a temperature of 35°C and 50% CO2 mortality of the tarsonemid mites is over 99.8%. No harmful irreversible results of CATT on vitality of mother plants in the field and runner production are found. From 2009 CATT is up scaled to a commercial level and widely applied by Dutch producers of planting stock. As a spin-off also plant parasitic nematodes are reduced by application of CATT. Understanding of the influence of different factors during CATT creates also possibilities for optimization this treatment to control P. penetrans and M. hapla in strawberry plants or in the soil particles attached to the roots. Application of an optimized CATT can prevent further dispersion of these plant parasitic nematodes in the strawberry chain