International Society for Horticultural Science (ISHS), Acta Horticulturae, 556, p. 545-552, 2001
DOI: 10.17660/actahortic.2001.556.79
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A preliminary study was conducted to verify the existence of cultivar-specific pollen surface alkane wax patterns in Corylus avellana L. 'Tonda Gentile delle Langhe', Corylus maxima Miller 'San Grato' and some hybrids obtained by crossing these two parents. Wax alkanes were chosen because of their good value as taxonomic markers and for the quickness and reliability of analysis, even on dry material. The presence of a waxy layer covering the pollen surfaces was confirmed by comparing hexane-extracted and nonextracted samples using transmission electron microscopy. Hexane extracts were analysed by FID gas chromatography and by GC-MS. Several n-alkanes (from C19 to C 35) and some iso-alkanes (2-methyl-C24, 2-methyl- C 24 and 2-methyl-C27) were detected. C. maxima was characterized by higher percentages of C24 and 2-methyl-C 24 when compared to C. avellana, which in turn had a higher content of 2-methyl-C24. The alkane composition of the F1 hybrids and the parents showed quantitative differences, and statistical analysis (principal component analysis) placed the F1 hybrids into two groups, each including one of the two parents. Hybrids BB8 and BB10, which have high yields and good flavor as well as resistance to Phytocoptella avellanae, were placed in the C. avellana group.