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Context. Detecting and characterizing circumstellar dust is a way to studythe architecture and evolution of planetary systems. Cold dust in debris disksonly traces the outer regions. Warm and hot exozodiacal dust needs to bestudied in order to trace regions close to the habitable zone.  Aims. We aim to determine the prevalence and to constrain the properties ofhot exozodiacal dust around nearby main-sequence stars.  Methods. We search a magnitude limited (H < 5) sample of 92 stars for brightexozodiacal dust using our VLTI visitor instrument PIONIER in the H-band. Wederive statistics of the detection rate with respect to parameters such as thestellar spectral type and age or the presence of a debris disk in the outerregions of the systems. We derive more robust statistics by combining oursample with the results from our CHARA/FLUOR survey in the K-band. In addition,our spectrally dispersed data allows us to put constraints on the emissionmechanism and the dust properties in the detected systems.  Results. We find an over-all detection rate of bright exozodiacal dust in theH-band of 11% (9 out of 85 targets) and three tentative detections. Thedetection rate decreases from early type to late type stars and increases withthe age of the host star. We do not confirm the tentative correlation betweenthe presence of cold and hot dust found in our earlier analysis of the FLUORsample alone. Our spectrally dispersed data suggest that either the dust isextremely hot or the emission is dominated by the scattered light in mostcases. The implications of our results for the target selection of futureterrestrial planet finding missions using direct imaging are discussed.

A near-infrared interferometric survey of debris-disc stars. IV. An unbiased sample of 92 southern stars observed in H-band with VLTI/PIONIER