Determination of Phenological and Chemical-Technological Indicators of Five Apple Cultivars under Climate Conditions of Pollozhan, Peshkopi, Albania

Abstract

The aim of this study was to determine the effects of climate conditions on duration of blooming and ripening phenophases, and chemical-technological indicators in five most used apple cultivars. The study was conducted during three consecutive years 2016-2018, on a 10-years old apple orchard, grafted onto M9 rootstock. A randomized complete design with five apple cultivars, 4 replications, with five apple trees and five branches for each variant on each replication, was used. Blooming and fruit ripening phenophases, and fruit quality indicators were determined by direct observation, numbering and measurements. Pink Lady was the earliest blooming cultivar (28th April), while Golden Delicious was the latest blooming cultivar (6th May). Duration of flowering varied from 10 days (Golden Delicious) to 15 days (Pink Lady). Ripening period varied from 130 days (Superstarking) to 191 days (Pink Lady). At harvest were measured the Dry Matter Content (DMC) (%), Total Soluble Solids (TSSC) (o Brix), Titratable Acidity (TA) (mg/100 g fresh fruit) and Vit C (mg/kg). Three-years mean of DMC varied from 14.2% (Superstarking) to 16.8% (Pink Lady), TSSC varied from 12.2 o Brix (Pink Lady) to 15.4 o Brix (Granny Smith), TAC varied from 0.395 to 0.730 mg/100 g fresh fruit (Superstarking and Granny Smith, respectively), and Vitamin C varied from 210.4 mg/kg (Golden Delicious) to 246 mg/kg (Granny Smith). Results showed that there exists a strong correlation between several chemical-technological indicators (r > 0.7). Relationship between cultivars, duration of phenological phases and fruit quality indicators was significant and statistically confirmed by ANOVA (p ≤ 0.05).