Effect of shading by coloured nets on yield and fruit quality of sweet pepper

Abstract

The concept of photo-selective netting was studied in a sweet pepper (Capsicum annuum L.) cultivar ‘Cameleon’ from summer cultivation in south Serbia (under high solar radiation 910 W m-2, with a photosynthetic photon flux density of 1661 μmol m-2 s-1), under four different coloured shade-nets (pearl, red, blue and black) with 40% relative shading. The aim of the study was to determine how different environmental control technologies, coloured shade-nets as net house or plastic-house integrated with coloured shade-nets, could influence plant parameters, production and quality traits in pepper fruits. Shade-grown leaves generally have higher total chlorophyll and carotenoid content than control leaves. Pericarp fruit thickness was significantly higher in peppers grown under red net house (4637.10 μm) and black net house (4609.32 μm) compared to the open field – control (3116.19 μm). The highest concentration of total soluble solids (TSS) was detected in pepper fruits grown under the open field conditions (8.03%). Pepper fruits grown in plastic tunnels had significantly lower TSS content (6.58%). Total acid (TA) content was 0.19 in the control and 0.25 in pepper fruits grown under red nets. The highest concentration of vitamin C was detected in peppers grown in plastic tunnels integrated with red coloured nets (175.77 mg 100 g-1). These results show that red and pearl photo-selective nets create optimal growing conditions and increase the total fruit yield as well as the number of fruits with fewer physiological disorders and with thicker pericarp. Photoselective pearl and red nets can be recommended for sweet pepper ‘Cameleon’ with respect to quality and bioactive compound and can furthermore be implemented in protected cultivation practices.