ISHS Acta Horticulturae 648: South Pacific Soilless Culture Conference - SPSCC
QUALITY CHARACTERISTICS OF FRAGARIA VESCA L. FRUITS INFLUENCED BY NFT SOLUTION EC AND SHADING |
| Authors: | G. Caruso, A. Villari, G. Villari |
| Keywords: | Alpine strawberry, hydroponics, solution concentration, double crop layer, berry chemical composition. |
| Abstract:
We report the results of research carried out in Campania between 2000 and 2002 with the aim of determining the fruit quality of everbearing alpine strawberry (local cv “Regina delle Valli”) grown under plastic (IR-PE) double-tunnels using the nutrient film technique (NFT). Comparisons were made of four electrical conductivity (EC) levels (1.3, 1.6, 1.9 and 2.2 mS•cm-1) of the nutrient solutions, in factorial combination with crops arranged in pairs on two vertical overlapped layers in a randomised split-plot design. A control crop was grown with the current technique in the same tunnels and the same density as with NFT, i.e. with plants spaced 25 cm along the row and in double-rows 40 cm apart on black PE mulched ridges (80 cm wide). Fruit obtained in spring, in comparison with the autumn, showed higher values of dry matter and refractive index, reducing sugars (glucose and fructose) and sucrose, acids (citric, malic, succinic and ascorbic), calcium, potassium, iron and chloride; in autumn, instead, magnesium, copper, nitrates, phosphates and sulphates were more concentrated in the fruit. The higher crop layer caused a greater accumulation of all the analytes, except for the nitrates which did not vary. The 2.2 mS•cm-1 treatment resulted in the highest levels of all the organic constituents; Fe, Cu, Zn and Cl showed a different trend, as the maximum concentrations corresponded to 1.9 mS•cm-1 EC. The control fruit attained, in autumn, the lowest values for most of the organic components and of the mineral anions, in comparison with those in hydroponics; only the inorganic cations were generally more concentrated with the traditional technique. In spring, the organic constituents and the mineral anions were again found in higher quantities in the fruits obtained by saline solutions, but only with regard to the higher crop level; by contrast, an intermediate accumulation of the minerals was recorded in the control, the four EC treatments within the lower layer which also often showed lower values of the inorganic cations. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
