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The turf-type bermudagrasses include diploid Cynodon transvaalensis Burtt Davy, tetraploid C. dactylon (L.) Pers., and sterile triploid hybrids produced by crosses of these species. The objective of thiis study was to develop a set of mierosatellite markers that could distinguish among commercially important turf-type cultivars. A genomic library enriched for tfie [CA/GT]^ repeat motif was constructed from DNA of the Tifway' fiybrid and sequenced to identify mierosatellite regions. Twenty-five microsatellite-flanking primer sets were developed and used to genotype two plant introductions and 12 turf-type cultivars. These primer sets produced an average of 10 amplicons across tfie 14 DNA templates. Sequences of selected amplicons revealed polymorphism resulting from expansion and/or contraction of the microsatellite and from indel mutations in the microsatellite flanking regions. As few as two primer sets were sufficient to differentiate all unrelated introduction lines and cultivars. Tfie primer sets failed to distinguish among closely related cultivars developed by selection of natural variants, but one primer set uniquely distinguished the cultivar TifEagle from its irradiated parent cultivar. Tfiese genomic microsatellites were not derived from gene coding sequences and will supplement tfie existing expressed sequence tag (EST)-based bermudagrass microsatellites. Tfiey will be most useful for evaluating tfie genetic diversity of Cynodon accessions and distinguishing among cultivars that exploit thils diversity.

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Pyrroles and Related Compounds. Part I . 3779 Pyrroles and Related Compounds. Part I . Syntheses ofXom,e Unsymmetrical Pyrrolylmethylpyrroles (Pyrromethanes).

Branched-chain sugars have been synthesised by the following route : (i) protection of a methyl glycoside a t all sites except that a t which branching is to be introduced; (ii) oxidation of the unprotected hydroxyl group to obtain a protected methyl glycopyranosidulose ; (iii) treatment of the oxidation product with a Grignard reagent and removal of protecting groups. In this way methyl 3,4-O-isopropylidene-~-~-erythro-pentopyranosidulose has been prepared and treated with a range of Grignard reagents, and, after further conversions, it has been possible to obtain L-arabinose derivatives which have a methyl, hydroxymethyl, or formyl side-chain of the type which occurs in natural products. Stereochemical correlations have been carried out. The methods developed have been used to synthesise L-hamamelose and its epimer (2-C-hydroxymethyl-L-arabinose) . Some attempts have been made to convert branched-chain glycosides into branched-chain deoxyglycosides by removal of the tertiary hydroxyl group.

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