In the Project is checked whether the volatile substances, biogenic volatile organic compounds (BVOC), which are produced by the in-vitro plantlet, or by bacteria which exist on it, can be measured by means of a novel technique: Selected Ion Flow Tube Mass Spectrometry ( SIFT-MS). This is an on-line mass spectrometer with enhanced selectivity and high throughput, which allows to make large numbers of measurements of the composition of the headspace of in vitro cultures. Applicants will investigate the proposed project or that way bacterial contamination and plant stress can be detected. It would eliminate the in vitro allow businesses with more certainty and subcultures to start indexes and infected cultures at an early stage. It can then also be taken appropriate measures to reduce stress in vitro plants. Thus the quality and production security of many millions of plants will be more secure. The target audience is primarily commercial in vitro companies in Flanders. This sector is small and all businesses -on one disadvantage to be included in the user group. In addition, the results are also useful for research laboratories of major plant biotech companies and research institutions.