Some Organic Farming Practices for the Production of Eggplant (Solanum melongena) and Okra (Abelomoschus esculentus) in Central Sudan

Abstract

In an attempt to produce eggplant and okra plants organically in central Sudan, (compost) as organic fertilizer, (neem seeds and hargal leaves water extracts) as organic insecticides, in different levels and concentrations were evaluated using split plot design. The results showed that mostly no significant differences were observed between the application of organic fertilizer, compost, and inorganic fertilizer, nitrophoska, in yield and yield components of eggplant and okra.Only in season 2002-2003, number of okra pods per feddan was significantly increased with compost application compared to nitrophoska application. All sprayed organic insecticides, neem and hargal, or inorganic insecticides, endosulfan and sumicidin, generally, did not significantly differ in their effects in yield and yield components of eggplant and okra. However, hargal spraying significantly increased the eggplant fresh weight in season 2001-02, compared to sumicidin treatment. In season 2002-03., neem treatment significantly increased the leaf area index, fresh and dry weights of okra plants compared to all other treatments.The total yield and number of okra pods per feddan was significantly increased with neem and hargal treatments compared to endosulfan, sumicidin and control treatments. The efficacy of organic insecticides and inorganic insecticides in reducing jassid population in eggplant and okra plants had followed the general trend of endosulfan, sumicidin, neem then hargal, mostly in all seasons. However, all tested organic and inorganic insecticides gave better results compared to control treatments. Sumicidin residues were detected in all tested samples of eggplant and okra fruits ranging from 18.7- 0.26 mg/ml. and were found up to 14 days after spraying. No significant differences were observed between the applications of 10 or 15 tons of compost per feddan in okra yield and yield components in season 2004-05, but generally, the application of 15 tons gave better results compared to 10 tons. In addition, the difference between the effects of all tested neem and hargal concentrations and their interactions in yield and yield components of okra were not significant. However, it was found that interaction of spraying of neem at 1.5 kg/40 L water and hargal at 0.88 Kg/16 L water significantly increased okra plant height compared to neem sprayed at 1 kg/40 L water and hargal at 0.44 Kg/16 L water.