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Cowpea [Vigna unguiculata (L.) Walp] is an important grain legume crop grown for its protein rich grains. It is an inexpensive source of protein in the diets of people in sub‐Saharan Africa. The International Institute of Tropical Agriculture (IITA) has been working on the improvement of cowpea for more than 30 yr. Over 60 countries receive cowpea cultivars improved by IITA for testing and adoption where needed. Many of these cultivars have identical parentage but look very different morphologically when grown in the field. Forty‐six microsatellite DNA markers were used to evaluate genetic similarities among 90 cowpea breeding lines developed at IITA. Twenty‐seven primer pairs could amplify polymorphic single‐locus microsatellites from all of these materials. Two to seven alleles per primer were detected with a polymorphic information content varying from 0.02 to 0.73. By means of only five polymorphic microsatellite primers, 88 of the 90 cowpea lines could be distinguished. A dendrogram based on the microsatellite polymorphisms generally agreed with the pedigree of the cowpea lines.

We isolated three dormancy-associated MADS-box (DAM) genes (MADS13-1, MADS13-2 and MADS13-3) and showed regulated expression concomitant with endodormancy establishment and release in the leaf buds of Japanese pear 'Kosui'. Comparative analysis between 'Kosui' and Taiwanese pear TP-85-119 ('Hengshanli'), a less dormant pear cultivar, showed reduction of MADS13-1 expression level in 'Hengshanli' earlier than in 'Kosui' towards endodormancy release, suggesting the possible relationship between chilling requirement and MADS13-1 expression. Application of hydrogen cyanamide accelerated endodormancy release with a reduction in MADS13 expression, whereas heat treatment in autumn inhibited endodormancy establishment without induction of MADS13 expression, indicating a close relationship between the MADS13 expression pattern and endodormancy phase transitions. Moreover, both the cis-acting regulatory elements and the methylation status in the 5' upstream region of the MADS13-1 gene were not largely different between 'Kosui' and 'Hengshanli'. Genomic structures of MADS13-1 from 'Kosui' and 'Hengshanli' revealed a 3218 bp insertion in the first intron of 'Hengshanli' that might be ascribed to the lower expression of MADS13-1tw; however, this insertion was also found in pear genotypes with a high chilling requirement. These results indicated that the low expression of MADS13-1 in 'Hengshanli' towards endodormancy release could not be explained by the identified cis-acting regulatory elements, the methylation status of the putative promoter or by intron insertion.

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