Agriterra, an AIM-listed pan-African agricultural company, pleased investors after reporting a production estimate of 2,700m barrels on the South Omo block in Ethiopia, in which the firm holds a one-fifth working interest. The estimate follows an independent assessment of the area, which covers 29,465 square kilometres and is part of one of the last great rift basins to be explored in East Africa.Tullow Oil owns a 50% stake in the asset, with the remaining 30% held by Africa Oil. Agriterra Chief Executive Officer Andrew Groves said: "With a gross unrisked best estimate prospective resource of 2.7bn barrels reported by Africa Oil for South Omo, the value of our stake in the block continues to appreciate. These results combined with successful drilling in the same petroleum system confirm the high prospectivity of the concession and we are extremely excited about the prospect of the first well being drilled by the end of the year."Agriterra reported that Sabisa-1, the first well planned for the South Omo Block, is targeted to be drilled by the end of 2012, following Tullow's rig contract negotiations in Ethiopia, which are nearing conclusion. The firm's share price rose 12.83% to 4.75p, while Tullow's fell 1.43% to 1,376p. NR