Net cover color influence nutritive quality of African nightshade and spiderplant

Abstract

ABSTRACTIndigenous leafy vegetables play a major role in strategies to attain food and nutritional security for African households. However, the potential of these vegetables in meeting the nutritional requirements have not been adequately exploited. This study assessed effects of shadenets on nutritive value of African indigenous leafy vegetables. The vegetables African nightshade (Solanum scabrum Mill.) and spiderplant (Cleome gynandra L.) and net covers colored white, gray, blue, and yellow, with unnetted plants as a control were used. From the 7th week after sowing (spiderplant) and transplanting (African nightshade) and at 2-week intervals nutritive quality variables were determined. Compared to open field, white net produced higher leaf β-carotene at 13 weeks after planting by 6% and 17% for African nightshade and spiderplant, respectively. Use of blue net cover reduced leaf vitamin C content by 94.5% and 79% in African nightshade and spiderplant, respectively, compared to open field at 15 weeks after planting. Higher leaf calcium was consistently recorded for plants grown under yellow net cover for African nightshade and white nets for spiderplant; but was reduced under blue net for both species on most sampling dates. Leaf iron content was maximized under yellow net cover for both crops. Use of net covers reduced leaf crude fiber content compared to open field; high leaf phenolic content was obtained in crops grown under white net for both vegetables. The crop responses were attributed to spectral quality, light intensity, and environmental changes to which the crops were subjected. The different colored agronet covers differentially influenced crop leaf nutritive quality.