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Variation in cold hardiness, assessed using the electrolyte leakage method, of three 6-7-year-old seedling populations of Acer platanoides (L.) originating from Sweden, Denmark and Germany (northern, central and southern population, respectively) was investigated in a Danish field trial during autumn and early winter. Simultaneously, autumnal changes in cold hardiness, stem water content and annual height growth were investigated in field-grown 3-year-old seedlings of the Danish population. The variation in cold hardiness among populations was structured as a moderate latitudinal cline, with the northern population cold acclimating earlier and/or faster than the other populations. Among the central and southern populations the latitudinal gradient was not apparent, resulting in approximately the same percentages of frost damage in the autumn. In early winter no differentiation in cold hardiness was observed among the three populations. In the Danish population cold acclimation was correlated with reduced water content and seedlings that grew longer in the autumn tended to dehydrate late. The results are discussed in relation to the transfer of A. platanoides seeds. [ABSTRACT FROM AUTHOR]

Evidence of the teleomorph Mycosphaerella graminicola (Fuckel) Schroeter (anamorph: Septoria tritici Rob. apud Destn.) in the Federal Republic of Germany Due to the fullfillment of certain biological requirements, the dominant occurrence of Septona tritici is restricted mainly to the milder climate of maritime regions. However, following mild winters in continental climatic zones, an increased and yield damaging appearance, which is additionally influenced by early sowing dates, can be observed. Previous proofs of the teleomorph Mycosphaerella graminicola (Fuckel) Schroeter were found in Australia, Brazil, Great Britain, Chile and the USA. With the first proof of teleomorph in Bavaria and herewith the complete life cycle, the optimum mechanism for an early and widespread primary infection of young wheat plants has been confirmed. [ABSTRACT FROM AUTHOR]