Optimum quality of this cucumber type at least in terms of
visual quality was achieved at around 3 weeks in both seasons.
However, cucumber fruits grown during the winter had a darker
and dull green skin color, and showed better quality than during
the spring. The main differences between the winter and spring
crops were the climate conditions, irrespective of the soilless
culture used. A parameter that relates the intercept radiation
and the thermal time in the time between anthesis and harvest,
G*
, has been defined and is proposed as a predictor of optimum
fruit quality. In order to obtain the best cucumber quality under
non-stressful conditions during fruit growth, the G* parameter
must be below 0.4 MJ m2 8C day1 interval1
, irrespective of
the season considered. In the winter season, the G* parameter
was sensitive enough to detect quality differences between both
hydroponics systems, but not during the spring season.
Although differences of cucumber fruit quality were mainly
due to climate conditions, in the NFT system fruit quality was
also improved with darker and dull green skin color (lower
lightness and chroma). During the spring season, NFT culture
offered fruit with lower acidity than perlite-grown fruit. This
M.D. Go´mez-Lo´pez et al. / Scientia Horticulturae 110 (2006) 68–78 77
result is explained in part by the about 1% higher nitrogen fruit
uptake that occurs in NFT (Go´mez et al., 2003b)