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Although native of temperate climates, grapevines are grownin Colombia in the department of Boyaca, between 2,200 and2,560 m a.s.l. Under these specific conditions, both the physicochemicalbehaviorof the fruit and its optimum harvest timeas measured in growing degree days (GDD) had remained unknownso far. On these grounds, in the municipality of Nobsa(Boyaca, Colombia),grapevines of the variety Pinot Noir werephysico-chemically characterized during their growth anddevelopment. Since day 21 after anthesis (DAA ) until overripening,the physicochemical characteristicsof 20 berries fromeach of three clusters we collected every week were carefullyassessed. A total of 826.2 GDD accumulated during fruit growthand development, thus completing 126 DAA . The accumulationof both fresh and dry mass followed double sigmoid curves.During early growth there was a decrease in pH, total solublesolids (TSS ) and technological maturity index (TMI =TSS /TTA ), coupled to an increase in total titratable acidity (TTA ).After this period and until harvest, pH, TSS and TMI increasedwhile TTA declined. Based on fresh mass, SST and TMI it waspossible to set optimum harvest time at 800.6 GDD.

Stress due to waterlogging is considered an abiotic factor that negatively affects crop production, which, together with the excessive fertilization of crops, reduces cost-effectiveness and generates the need to create sustainable alternatives economically and environmentally. The effect of inoculation with Azospirillum brasilense on the physiology of the Raphanus sativus var. Crimson Giant subjected to waterlogging, was evaluated. Stomatal conductance, chlorophyll concentration and chlorophyll a fluorescence were analyzed to establish this effect, corroborating the beneficial effect of inoculation with A. brasilense in radish under waterlogging stress. The stomatal conductance of inoculated and waterlogged treatments presented the same values as the control plants, and photosystem II efficiency was favored in inoculated and waterlogged treatments (0.6 Fv/Fm) compared to non-inoculated and waterlogged treatments (0.3 Fv/Fm). The results suggested that this increased efficiency was due to the preservation of photosynthetic pigments in the tissues, allowing the preservation of stomatal conductance and a reduction in the amount of energy dissipated in the form of heat (fluorescence) due to inoculation with A. brasilense. Therefore, plant growth-promoting bacteria are responsible for activating and improving some physiological mechanisms of the plant. [ABSTRACT FROM AUTHOR]