Abstract:
The nutritional importance of roselle calyces depends upon their chemical composition. Afield experiment was conducted for two consecutive summer seasons (2011 and 2012) at the Top Farm of the Faculty of Agriculture, Omdurman Islamic University (Fitaihab). The work was conducted to investigate the effect of chemical and organic fertilizers on some chemical components of calyces and seeds of two roselle ( Hibscus sabdriffa L.) varieties. The experiment was set in a split- plot design with four replications. The treatments were two varieties namely, Bulk (V1 – local) and Omshiback (V2- improved). Chemical fertilizers involved 0, 40, 80 kg N/fed and 40 N + 40 kg P2O5/fed, beside 2 tons chicken manure/fed and 3 tons cattle manure/fed (denoted as T0, T1, T2, T3, T4 and T5, respectively). Calyx chemical components taken were calyx anthocyanin content (%), calyx protein content (%) and calyx phosphorous content, in addition to seed oil content (%). The findings of the study revealed that all studied calyx chemical components (anthocyanin, protein, phosphorous) and oil content in both seasons were not significantly affected by varieties, fertilizers and their interaction, except P content, which was significantly affected by fertilizers in both seasons. In the first season, T5 treatment significantly increased calyx phosphorous content relative to T0, T1, T2, T3 and T4 treatments by about 21.9%, 25.0%, 16.0% and 14.2%, respectively, whereas T2 treatment in the second season significantly increased it as compared to T0, T1, T3, T4 and T5 by about 31.8%, 16.0%, 41.5%, 18.4% and 11.5%, respectively.
