Effect of endophytic bacteria Bacillus subtilison metabolic processes in potato tubers during storage

The article examines the effect produced by the preplant inoculation of potato tubers with Bacillus subtilis on biochemical processes occurring in the tubers of a new crop during the postharvest period at different storage periods. The content of malondialdehyde in tubers treated with strains 10-4 and 26D decreased by 15.5 and 35.5% and by 14.9 and 13.6% relative to the control after one and six months, respectively. The proline content in tubers pretreated with strain 10-4 differed insignificantly from the control in both storage periods, while in the case of strain 26D, it was lower than the control by 14.7 and 26.3%. First, the activity of protective proteins in treated tubers decreased relative to the control; then, the activity of trypsin inhibitors in tubers was found to significantly exceed that in tubers stored for a short time. The protein content of pretreated tubers was initially higher than that of the control; then, it was either at the same level (strain 26D) or 15% lower than the control (strain 10-4). The content of ascorbic acid in tubers pretreated with strain 10-4 exceeded that of the control by 16.1 and 17.9% after one and six months of storage, respectively, whereas in the case of strain 26D, no difference from the control was noted. The amount of reducing sugars was 39.4% lower than the control after one and six months of storage (strain 10-4) and 35.6% after six months of storage (strain 26D). The pretreatment with strains 10-4 and 26D positively affected the main biochemical parameters of tubers during long-term storage, providing a protective effect and preserving the biological value of produce.