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21.
Genetic diversity in forest coffee (Coffea arabica L.) was estimated using inverse sequence-tagged repeat (ISTR) markers. One hundred ninety two samples representing 16 populations
of C. arabica from four regions of Ethiopia were analyzed with 12 pairs of forward and backward ISTR primer combinations. A total of 144
reproducible bands were generated out of which 37 (25%) were polymorphic and scored as present (1) or absent (0) data matrix.
This data was used to compute Jaccard coefficient to estimate genetic variability among all possible pairs of samples. The
proportion of polymorphic bands within populations ranged from 19% for Bale-3, to 54% for Walega-2 populations. Un-weighted
pair group method with arithmetic mean (UPGMA) based cluster analysis generated two clusters at 56% similarity value. The
samples were clustered on the basis of their geographical origin, which could be attributed to a few region specific banding
patterns detected. However, within regions most of the samples failed to cluster on the basis of their respective populations,
which may be due to the presence of substantial gene flow between local populations in the form of seedlings carried out by
farmers. The results may provide information to develop strategies for in situ conservation. 相似文献
22.
The aquatic chemistry of a reservoir in a snowy area on the Japan Sea side of Hokkaido Prefecture in northern Japan was investigated during the 1999 thaw season. We observed slight and brief acidification, during which period the dissolved aluminum increased. The variation in its concentration was similar to that in dissolved organic carbon. 相似文献