Effect of nutritive solution EC and shading on berry chemical composition of NFT-grown �Friariello� pepper.

We report the results of research carried out in Campania in 2002 and 2003, during winter-summer period, with the aim of determining the fruit chemical composition of Capsicum annuum L. var. Longum, also known as “Friariello” pepper (local cv Nocera) grown under double plastic film (IR-PE) polytunnels and fed by nutritive solutions (3.0 l•min-1 flux) including 6 macro- (N, P, K, Ca, Mg, S) and 7 microelements (B, Cl, Fe, Mn, Mo, Cu, Zn). Comparisons were made of four nutritive solutions differing in electrical conductivity (EC) levels (3.5, 3.8, 4.1 and 4.4 mS•cm-1), in factorial combination with crops arranged in pairs on two vertical overlapping layers; a split-plot design was arranged and each randomised treatment included 12 plants with three replications. A pepper control crop was grown in the same tunnels with the current technique, i.e. with plants spaced 30 cm along the row and in double rows 40 cm apart (achieving the same density of 5.3 plants per m2 as with NFT) on black PE mulched ridges (80 cm wide). Fruit samples were harvested, for analyses, at the beginning of June in all the experiment plots. On average, the upper crop layer resulted in a higher concentration of both the organic and mineral constituents, except for the nitrates and sulphates which were higher in the fruit produced by lower layer plants. Of the nutritive solution ECs, the 4.4 mS•cm-1 treatment caused the highest levels of all the organic and mineral constituents. The fruits harvested in the plots managed by traditional techniques generally showed lower amounts of both organic and mineral substances, whether in the upper or the lower crop layer.