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In this paper, the variability of six Pinus brutia var. brutia populations was analyzed in relation to their needle flavonoid composition. In all trees, two proanthocyanidins: prodelphinidin and procyanidin, and six flavonols: myricetin, quercetin, larycitrin, kaempferol, isorhamnetin and syringetin were detected and measured by HPLC. The relative proanthocyanidin composition was remarkably constant from one provenance to another. On the other hand, total proanthocyanidin concentrations as well as relative isorhamnetin contents showed significant differences between the populations studied. Total proanthocyanidin contents distinguished two populations from Crete and Turkey from all the others, whereas relative isorhamnetin contents split the species into two main eastern and western groups in accordance with terpene and isozyme data.

A total of 120 individual trees representative of Pinus uncinata were analysed for their foliar flavonoid content. The ratio of two extracted anthocyanidins, prodelphinidin and procyanidin, is a constant. Among the flavonols quercetin, kaempfrerol and isorhamnetin, the percentage of quercetin discriminates the five studied populations. Its distribution conforms to the Hardy-Weinberg law, but the ratio of the two implicit alleles proves the originality of each population, and leads to the recognition of distinct chemotypes.

This paper describes a method for discriminating and identifying 10 successful Douglas-fir (Pseudotsuga menziesii var. menziesii) clones using foliar flavonoids. All the 101 individuals analyzed by high performance liquid chromatography contained two proanthocyanidins: prodelphinidin and procyanidin and six flavonols: myricetin, quercetin, larycitrin, kaempferol, isorhamnetin and syringetin, but in different proportions. The experimental protocol used was very reproducible since the variation coefficients for each flavonoid did not exceed 9%. Submission of the flavonoid data to multivariate discriminant analysis allowed excellent discrimination of the 10 clones with 89% of the individuals being well-grouped. Then a clonal bank was established in which the fingerprint of each clone is defined by its position in the multidimensional space of the discriminant analysis. The clonal identity of several unknown individuals was determined with success by projecting their flavonoid data in a subsequent discriminant analysis.

In Ephedra andina, E. breana and E. frustillata three colourless compounds are present which upon treatment with mineral acid yield delphinidin, pelargonidin and apigeninidin. Prodelphinidin is present in young shoots, while the other two compounds occur in subterraneous parts and, in smaller quantities, in older shoots. There is evidence that the substance yielding delphinidin is an oligomer of higher molecular weight, which due to its tanning capacity may provide chemical defence. The substances which yield delphinidin and apigeninidin are probably monomers or dimers of lower molecular weight; no ecological role can be indicated for them.