Proteomic changes and endophytic micromycota during storage of organically and conventionally grown carrots

Summary

The physiological state of carrot roots during extended cold-storage is decisive for high postharvest quality. Wehave investigated differences in the proteome and micromycota of organically and conventionally grown carrots during six months of storage. The levels of only 15 proteins changed in level during storage. Proteins involved in cold stress adaptation and cytoskeleton components changed; these changes in specific protein levels occurred mainly during the first month demonstrating adaptation to storage conditions and that the carrots were subsequently stable, indicating stable carrot quality. The changes observed were similar in the two cropping systems. Using both biological isolation and a fungal PCR targeting the ITS region, we identified several endophytic species belonging to the Ascomycota. The most frequently encountered taxa were Tetracladium, Leptodontidium, Nectriaceae andPhomawhich areknownto occur as root endophytes or as root-associated fungi. As for the proteomics data, no consistent statistically significant differences in micromycota were observed between the two cropping systems. Weconclude that cropping system did not have an influence on the postharvest quality of the carrots during six months of cold storage.