DOES THE USE OF ANTI-HAIL COVER AFFECT THE QUALITY STANDARDS, THE METABOLIC PROFILE AND THE CELL WALL ENZYMES ACTIVITIES OF BLUEBERRIES?

MORALES, LUISINA; GOLLÁN, AGUSTÍN; BELLO, FERNANDO; RIVADENEIRA, FERNANDA; VÁZQUEZ, DANIEL; TRIPODI, K.E.J.

Congreso; Congreso de SAIB; 2021

SAIB

The use of anti-hail covers (AHC) has increased over the last years in the North Eastern of Argentina. Its use is intended toprotect crops against hail and torrential rains, as well as to reduce the impact of the negative effects of atmospheric adversities,sudden changes in temperature or intense winds. However, it is known that this practice may modify the orchard microclimate,potentially affecting the fruit organoleptic quality. The present study aimed to evaluate the effect of AHC in the biochemicalbackground and internal quality parameters of two broadly grown blueberry (Vaccinium corymbosum) cultivars, ‘Emerald’and ‘Snowchaser’, at full harvest. The study was conducted in commercial blueberries orchards during the 2018/2019 periodsat Concordia (Entre Ríos). The strategy also included the measure of total phenolic compounds (TPC), the activity of enzymesconnected with the cell wall and the content of metabolites by GC-MS. It was found that the effect of growing conditions onquality parameters was more evident in 2018 than in 2019 for ‘Snowchaser’ while the opposite happened for ‘Emerald’. Inboth seasons and condition of growth, the traits that significantly changed, were always higher for ‘Emerald’. Regardingtexture, one of the most appreciated traits, it was either higher under AHC or it did not change with treatment (‘Emerald’,2019). The photosynthetically active radiation was reduced on average by 17 % in both seasons for fruit grown under AHC;as a consequence, a mean delay of ten days was registered for each phenological stage in both varieties. Regarding the TPCand the activities of cell wall related enzymes, they differed with season and variety but were not affected by growth conditions.As a whole, fluctuations were more evident in season 2019. ‘Snowchaser’ held less TPC and b-gal activity than ‘Emerald’,but higher PME and pectinase activity. This last finding could explain the lower firmness of the first variety in the field grownfruit, but the same argument is not applicable to fruit grown under the net, that showed higher firmness.The content of severalcompounds, such as sugars, organic and amino acids, was higher in ‘Emerald’ under AHC. It is predictable that this wouldhave a positive effect in the final taste of this berry. The same can be foreseen by aspartic acid content, an amino acid relatedwith umami flavour, as glutamic acid. The attributes that featured the field grown fruit from ‘Snowchaser’ were citric, malicand glucuronic acids, while threalose and raffinose were higher under AHC growth conditions. It can be concluded that theuse of protective nets in berries culture is a good alternative to deal with unfavourable climate conditions, since it did not alterto a large extent their agronomic traits. However, there exist varietal differences. In fact, ‘Emerald’ responded better in generalto the net application, since all measured traits either did not change or even improved in relation to field growth.