Genetic diversity of traditional varieties of upland rice from Vietnam and prospects offered by improved varieties.

摘要

Despite its recent decline, upland rice is still an important food crop for ethnic minorities in Vietnam. As a result of the decrease in area, genetic erosion is a problem and collections were organized to protect biodiversity. The genetic diversity of a sample of 200 traditional upland rice varieties collected in Vietnam has been analysed. Approximately three quarters of the varieties are belonging to the japonica type and a quarter are indicas. The allelic diversity is similar to that found in upland rice cultivars from neighbouring countries. Above all, traditional upland rice varieties from Vietnam are photoperiodic and very late maturing. Introducing varieties with a shorter duration would enable cropping systems to be intensified by growing a second crop on residual soil moisture. Short duration improved varieties from various origins have been introduced and tested in two ecological situations corresponding to those of upland rice growing areas in Vietnam. Some preliminary results are presented here as well as perspectives for future collaboration.