Effect of different soil management practices on grapevine growth and on berry quality assessed by NIR-AOTF spectroscopy.

摘要

Soil cultivation practices and climate significantly affect vine growth and grape characteristics. Considering agronomical and seasonal variability viticulturists need for simple, rapid and cost-effective techniques to assess grape composition and harvesting time. The experiments were carried out during 2010 and 2011 in a 6-year-old vineyard grown in Viterbo (Centre of Italy) with the aim to evaluate the influence of soil management on vine growth and grape quality. Since vineyard establishment two different soil cultivation practices were carried out: complete bare soil, by mechanical tillage, and natural permanent vegetation. The grape cultivars selected for the experiments were 'Canaiolo nero' and 'Trebbiano giallo'. Data on vine growth, phenology and yield were collected during the two growing seasons and a NIR (Near infrared) - AOTF (Acoustic Optically Tuneable Filter) spectrophotometer was tested during ripening to monitor total soluble solids (TSS) (Brix), pH, titratable acidity, anthocyanins and total phenols of Canaiolo n. and Trebbiano g. grapes. Reference destructive analyses on the same qualitative grape parameters were carried out at the same time and the results were compared with NIR results. Differences referable to soil management were detected on vine growth, bud break time and on grape quality, particularly for TSS and anthocyanins content. High correlation was found between NIR values and destructive analysis values of titratable acidity and pH. PLS model for anthocyanins prediction in Canaiolo n. samples has shown an excellent performance with a R2cv (coefficient of determination for cross validation) of 0.90 and a SECV (standard error of cross validation) of 45.15 mg/kg. Results show the influence of soil management practices on vine and grape characteristics and the great potential of NIR-AOTF spectroscopy as fast technique for grape quality assessment.