Evaluation of insecticidal botanicals against sorghum covered smut (Sphacelotheca sorghi) at Wag-Lasta areas, Ethiopia

Abstract

Sorghum is the main staple food. Smut is one of the main diseases of Sorghum in the area. The experiment was conducted at Sekota Dryland Agricultural Research Center for two consecutive cropping seasons. The aim was to determine the effectiveness of some botanicals in controlling covered smut on sorghum. These botanicals were compared with Thiram chemical and an untreated check. Smut inoculated sorghum seed was treated with dried and grounded powder materials of each botanical at a rate of 6 gram per 100 grams of seed by mixing thoroughly with little water and put for 24 hours and then air-dried before planting. Sisal aqueous solution was extracted from sisal fresh leaves at a rate of 10 ml for 100 grams of seed. The individual and combined results showed that Sisal and Thiram significantly (P ≤ 0.05) controlled the disease more than others. Infection percentage and number of infected plants by covered smut were significantly (P ≤ 0.05) reduced and the higher yield was gained on both treatments. The partial budget analysis also revealed that Sisal had 8,184Ethiopian birr over negative control and 1149Ethiopian birr over positive control as an economic advantage besides its accessibility and environmental soundness. The overall result and partial budget analysis indicated that the use of Sisal leaf extract, as a seed treatment against sorghum covered smut is potentially useful for smallholder farmers of Wag-Lasta and similar sorghum producing Agro-ecological areas.

Keywords

• covered smut
• disease
• sorghum
• botanical
• extract
• powder