a1 CIRAD-Forêt, B.P. 1716, Dakar, Senegal
a2 ISRA/D.R.P.F., B.P. 2312, Dakar, Senegal
a3 ENSA Thiès, B.P. A 296, Thiès, Senegal
a4 PRONASEF, B.P. 3818, Dakar, Senegal
Seeds of four African tree species from the Sahelian zone (Boscia senegalensis) and the Sudanian zone (Butyrospermum parkii, Cordyla pinnata and Saba senegalensis) lose viability after moisture contents drop below 22 and 30%, depending on the species. Seed longevity in wet and airtight storage does not exceed a few months. Temperatures close to zero elicit symptoms of chilling injury leading to rapid seed death. The optimum storage temperature is 15°C. These results allow the four species to be classified as recalcitrant seed species. Boscia senegalensis is therefore an exception in arid zones where most species have orthodox seeds.
(Received May 25 1999)
(Accepted February 01 2000)