PRESERVATION OF GENETIC RESOURCES SHOWN FOR THE EXAMPLE OF ANNUAL MEDICAGO SPEC. ECOTYPES IN MOROCCO

摘要

In the present study 411 autochthonous annual Medicago spec, ecotypes were collected at 108 sites and evaluated as to their potential agricultural use. With increasing rainfall and altitude of collection sites a decrease was recorded in the length ofsprouts, sward hight, leaf size, and in dry matter yield, High rainfall regions were found to select late flowering ecotypes. Autochthonous Medicago spec showed broad intraspecific variation in seed yield, begin of flowering, and in seed weight. No relation was found between collection site and coumestrol content In a field trial comparing 112 ecotypes with introduced cultivars at two contrasting sites, thirty ecotypes proved to be better adapted to the local conditions than the cultivars. In conjunction with the findings of Aabbar (1995) this survey has led to the proposal of three Medicago ecotypes for accession to the national Moroccan seed catalogue SO.NA.COS. (Societe nationale de la commercialisation de sentences). Of the 18 Medicago species previously described in Morocco, only 10 species were observed during the three intensive collection tours in 1988. The following strategies should be implemented to prevent further loss through the ongoing erosion: (a) ex situ conservation in both nationaland international genebanks; (b) in situ conservation at the sites of origin; (c) trainee programme for staff working on plant genetic resources; and (d) participation of farmers in in situ conservation.