Precautions for harvest, sampling, storage, and transport of crop plant metabolomics samples

Plant metabolomics is increasingly a routine option for plant biologists and food scientists. Here, we suggest some precautions for preparation and handling of samples issued from crop plants, in order to ensure sample representativeness and quality before their biochemical analysis. These precautions concern organ harvest either in the greenhouse or in the field, transport to the laboratory, and sampling, as well as sample pooling, storage, and transport to the analytical laboratory. They are in agreement with the recommendations of the "Plant Biology Context" group of the Metabolomics Standards Initiative concerning reporting practices for sample preparation. Some quality checking methods for long-term stability of metabolomics samples are also covered. The corresponding experimental procedures are illustrated using a representative study on melon fruit.