GEOGRAPHIC-VARIATION IN TETRAPLOID WHEAT (TRITICUM-TURGIDUM SSP TURGIDUM CONVAR DURUM) LANDRACES FROM 2 PROVINCES IN ETHIOPIA

There is considerable wealth of genetical and morphological variation in tetraploid wheat collected from Ethiopia by past expeditions. Sever al authors have speculated on the reasons for this concentration of di versity so far removed from the centre of origin of wheats in West Asi a. The present study reports results of evaluation carried out on mate rial collected in the early 1970's from Ethiopia. The landraces from t he two provinces Shewa and Tigray were found to be distinctly differen t. This divergence was attributed to the differences in environmental conditions between them. Wide differentiation among landraces within e ach province was also present. The Ethiopian farmer's practice of grow ing composite cultivars in the field has resulted in bulk samples of E thiopian landraces containing several agrotypes. The proportion of tot al variance due to differences among agrotypes within landraces was by far the greatest found in this study, followed in most cases by the v ariation among landrace populations within provinces which exceeded, i n turn, the variation between province gene pools. The optimal strateg y for further germplasm collections and implications for improvement a nd conservation in focally-based community gene banks are discussed.