ANNUAL MEDICAGO SPECIES ON NONALKALINE SOILS IN MOROCCO

Autochthonous annual Medicago spp. were collected on non alkaline soil s and evaluated for potential agricultural use in Morocco. 411 ecotype s were collected at 108 sites in spring 1988 before plants mature. Of the nine Medicago species collected, M. polymorpha and M. tornata were the most frequent. The distribution of Medicago ecotypes in relation to quantitative descriptions of the edaphic and climatic environment w as studied. Due to the available number of ecotypes only M. aculeata, M. murex, M. polymorpha, M. tornata and M. truncatula were included in the statistical analysis. Nodulated M. polymorpha and M. truncatula e cotypes were found at sites with pH value as acid as 4.0 and 4.1 resp. In a cross-tabulation dependance of species occurrence and annual rai nfall resp. altitude of collection sites is shown. A discriminant func tion analysis emphasizes that altitude is the most important variable while pH is the least important among seven environmental factors cons idered for species occurrence. In a field trial comparing 112 ecotypes with nine introduced cultivars at two contrasting sites 30 ecotypes w ith promising agronomic characteristics were identified.