The study was undertaken to identify the effect of different shading net on the quantum efficiency of PS II on ‘Star Flame’ chilli pepper (Capsicum annuum) over a period of time cultivated under plastic house environment. ‘Star Flame’ pepper was grown under red shading net and samples without shading were used as control. Analysis of photo...synthetic activity revealed a significant difference (p<0.05) between Fv/Fm values in control and red shading at the end of July (p = 0.031) after the first harvest. Chlorophyll fluorescence parameter Fv/Fm reflects the maximum quantum efficiency of photosystem II (PS II) used in the detection of early stress in plants.
The effect of irrigation on tomato yield depends on the actual weather conditions, basically the air temperature and precipitation (quantity and dispersion). The irrigated plants gave a significantly higher yield, and rainfed plants showed a yield loss. The optimum water supply treatment gave a significantly higher proportion of lycopene than the ...control (rainfed) treatment (89% and 80% respectively) in case of Brixsol F1 variety. In spite of this we have not found significant difference in case of Strombolino F1 (cherry type). Content of total poly-phenols measured in Strombolino F1 (cherry type) was significantly higher than that found in the Brixol F1 (normal type). The optimum water supply treatment resulted in a significantly lower content of total polyphenols in both years. Tomato fruits are rich in polyphenols the largest amount of which is rutin from among the identified components.