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Gilles Bezançon Jean-Louis Pham Monique Deu Yves Vigouroux Fabrice Sagnard Cédric Mariac Issoufou Kapran Aïssata Mamadou Bruno Gérard Jupiter Ndjeunga Jacques Chantereau 《Genetic Resources and Crop Evolution》2009,56(2):223-236
Changes in the diversity of landraces in centres of diversity of cultivated plants need to be assessed in order to monitor
and conserve agrobioversity—a key-element of sustainable agriculture. This notably applies in tropical areas where factors
such as increased populations, climate change and shifts in cropping systems are hypothesized to cause varietal erosion. To
assess varietal erosion of staple crops in a country subjected to various anthropogenic and natural environmental changes,
we carried out a study based on a comparison of the diversity of pearl millet and sorghum varieties collected in 79 villages
spanning the entire cereal-growing zone of Niger over a 26 year period (1976–2003). For these two crops, the number, name
and type of varieties according to important traits for farmers were considered at different spatial scales (country, region,
village) at the two collection dates. The results confirmed the high diversity of millet and sorghum varieties in Niger. No
erosion of varietal diversity was noted on a national scale during the period covered. Some changes were observed but were
limited to the geographical distribution of certain varieties. This highlights that farmers’ management can preserve the diversity
of millet and sorghum varieties in Niger despite recurrent and severe drought periods and major social changes. It also indicates
that rainfed cereal cropping systems in Niger should remain to be based on millet and sorghum, while reinforcing farmers’
seed systems. 相似文献
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M. G. Salas Fernandez I. Kapran S. Souley M. Abdou I. H. Maiga C. B. Acharya M. T. Hamblin S. Kresovich 《Genetic Resources and Crop Evolution》2009,56(7):991-1000
Sorghum is a good candidate crop for breeding to increase provitamin A, i.e., biofortification. Yellow endosperm sorghums
contain carotenoids, including precursors of vitamin A, and sorghum is a major staple crop in areas of Asia and Africa where
vitamin A deficiency is prevalent. Our objective was to collect and characterize yellow endosperm sorghums as a potential
new source of genetic diversity to increase provitamin A content. A set of 164 landraces were collected from southern Niger
and northern Nigeria. The most important use of these cultivars was as food. The endosperm exhibited a significant variation
in yellow intensity. Lutein, zeaxanthin and β-carotene were the most abundant carotenoids in the ten landraces with the most
intense yellow color. Cluster analysis, principal coordinate analysis and population differentiation test revealed that this
set of 164 landraces represent a new genetic pool that might increase the genetic diversity of yellow endosperm sorghums in
applied breeding programs. 相似文献
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