Recently, the demand for baby spinach (Spinacia oleracea L.) far exceeds the supply because of its health attributes and ease to use as leafy vegetable (Cocetta et al., 2014). Baby spinach is grown all year round in temperate regions (Rodríguez-Hidalgo et al., 2010). Baby spinach is considered to contain relatively high amounts of carotenoids (Bergquist et al., 2006), flavonoids, and phenolic acids (Fallovo et al., 2009). These biological compounds are reported to reduce chronic diseases, viz., heart-related diseases (Shashirekha et al., 2015), prostate cancer (Neuhouser, 2004), and dementia (Commenges et al., 2000).
The recent rise in global warming across the world has posed severe challenges to crop production. Among others, the challenges include increase in air temperature (AT) and intensity of solar radiation (Meena et al., 2014). Thus, more advanced and innovative practices are required to mitigate such challenges with less energy cost. The most efficient method will possibly be the use of shade nets because they can modify environmental conditions. Photoselective nets have been used to improve crop productivity and protect against pests and physical damages (Selahle et al., 2014).
Owing to adverse climate change, agronomic practices such as shade netting have been established in the past decade with the aim of filtering selective regions of the spectrum from natural radiation (Stamps, 2009). The use of colored shade nets creates favorable microclimate and provides physical protection to the crops (Oren-Shamir et al., 2001; Shahak et al., 2008), thereby improving the quality of vegetables.
The acceptability of processed produce by consumers relies on two fundamental quality parameters, visual appearance and texture (Toivonen and Brummell, 2008). Cultural practices such as sowing and harvest time (Bergquist et al., 2007a), irrigation (Pellegrini et al., 2003), mineral nutrition (Zikalala et al., 2016), industrial processing (Hodges and Toivonen, 2008), and postharvest storage temperature and duration (Mudau et al., 2015) have been reported to improve nutritional quality of baby spinach. Meena et al. (2014) demonstrated that light intensity, incoming radiation, and canopy temperature were significantly reduced under protected shade nets. Bergquist et al. (2007a) reported that shade nettings reduced flavonoid concentration in baby spinach ranging between 15% and 24%. In another study conducted by Bergquist et al. (2007b), baby spinach grown under shade nets showed significantly higher concentrations of total carotenoids and total chlorophylls. The authors further observed that the effect of shade nettings also significantly decreased ascorbic acid concentration. Data that describe the effect of a wide range of photoselective colored nets on the postharvest quality of baby spinach are lacking in South Africa. Therefore, the aim of this study was to investigate the effect of photoselective nettings on growth, productivity, and postharvest quality attributes of baby spinach.
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