The situation of the wild pear (Pyrus pyraster (L.) Burgsd.) in Switzerland: morphological characterisation, differentiation from the cultivated pear and degree of purity in its occurrence.

摘要

Wild pear (Pyrus pyraster) is one of Switzerland's rare and endangered tree species. However, the similarity between wild and cultivated forms makes the conservation and promotion of the species difficult and the current status and situation of wild pear is therefore largely unknown. The aim of this investigation was to find suitable traits or trait combinations that would allow us to identify and distinguish between the two forms and to estimate the degree of purity of the remaining populations. For this purpose 220 wild pears from 13 natural populations and 30 cultivars from two production orchards were selected. Ten leaf and fourteen fruit traits were measured and analysed with multivariate statistics. Wild and cultivated pear can be distinguished with a very high precision when fruit traits are available, but with far less accuracy when only leaf traits are used. Fruit size, taste and colour, and to a lesser extent, leaf size and presence or absence of spikes are best suited for species identification. Classification based on discriminant analysis delivered correct results for 97% of the classified trees. The native populations of wild pear in Switzerland have maintained a high degree of purity. Only 5% of the sampled wild pears showed some characteristics of cultivation.