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Biogenic volatile organic compounds (BVOC) are mainly emitted from vegetation. However there is still little information on BVOC exchanges with crops. In this study we measured fluxes of BVOC from wheat, maize and rapeseed crops near Paris at the plant level during a full-week period for each species. We used dynamic automated chambers coupled to a Proton Transfer Reaction, Quadrupole ion guide, Time of Flight mass spectrometer (PTR-Qi-Tof-MS) instrument for online measurements of BVOC. Our results confirm the hypothesis that many unexplored compounds contribute to BVOC exchanges between crops and the atmosphere, although for all plant species methanol was dominating the emissions (55–85% of the sum of the BVOC exchanges fluxes on a mass basis) followed by acetone and acetaldehyde. The 10 most exchanged compounds, excluding methanol, contributed more than 50% of the summed fluxes and the 100 most exchanged contributed to more than 90%. The summed BVOC emission and deposition presented large interspecies variations, but limited intra-species variability, with a summed net flux of 0.11 ± 0.02 μgBVOC g DW −1 h−1 for maize, 1.5 ± 0.7 μgBVOC g DW −1 h−1 for wheat, and 9.1 ± 2.4 μgBVOC g DW −1 h−1 for rapeseed. The 10 most emitted compounds were mostly emitted during the day and were correlated with both photosynthetically active radiation and temperature and anti-correlated with relative humidity. This study provides the first evaluation so far of the biosphere-atmosphere fluxes for several BVOC. In particular we provide a first evaluation of standard emission factor for isoprene and monoterpene for wheat and rapeseed at their respective growth stages. This study is however limited to a week period at a given stage for each species and at the plant level. Image 1 • VOC fluxes from wheat, maize and rapeseed plants were measured during a week period. • Dynamic automated chambers coupled to a PTR-Qi-Tof-MS were used. • Methanol was the main emitted compound, followed by acetone and acetaldehyde. • The 10 most exchanged compounds, excluding methanol, contributed more than 50% of the summed fluxes. • The 100 most exchanged contributed to more than 90% of the summed fluxes. [ABSTRACT FROM AUTHOR]