Abstract:

【Objective】 Taking the Chardonnay grapes in Huailai county, Hebei province as the object of this study, the effects of temperature, duration of sunshine on the grape maturity indices were analyzed. 【Method】 Based on five-year field test results in 2004-2008 and meteorological conditions, a comprehensive analysis was made using the correlation analysis, principal component analysis, regression analysis and variance analysis methods.【Result】The results showed that the highest temperature in April, mean temperature of May, the lowest temperature in May, the highest temperature in July and duration of sunshine in July were the most important factors affecting total sugar content of Chardonnay grape. Active accumulated temperature in May, the highest temperature in June had a significant effect on the total acid content. Active accumulated temperature in May, duration of sunshine of August, the highest temperature in August and September had a significant effect on sugar/acid ratio. Active accumulated temperature in April, duration of sunshine in July were the most important factors affecting pH value (0.05 level). 【Conclusion】In Huailai region, temperature and duration of sunshine have different effects on the Chardonnay grapes’ sugar content, acidity content, sugar acid ratio and pH value at different stages of growing season.

Key words: grape, Chardonnay, temperature, duration of sunshine, maturity indices, Huailai