Death of trees in forest and fruit orchard ecosystems caused by unspecific decline diseases - A comparative analysis
1998
Vajna, L. (Magyar Tud. Akad., Budapest (Hungary). Novenyved. Kutatoint.)
The analysis indicates the similarities and differences of tree- and stand-level decline in two different ecosystem. The syndromes are similar. The role of man in the occurence of fruit tree decline is decisive. Economical restructring and the changes in ownership of farm lands influenced strongly the health conditions of Hungarian orchards. Decline in forest ecosystems: tree decline, stand-level forest decline are the consequences partly of selfthinning, of short term climatic fluctuations, of climate change, and anthropogenic disturbances. Decline as a phenomenon may play the role of regulation of forest tree population, a process of selection, a force of negative succession of forest ecosystems. The role of biotic and abiotic and anthropogenic factors are discussed in connection with the decline phenomenon. The analysis demonstrated the role of decline pathogen fungi and shows the basic similarity in species which take part in the process in forest and fruit orchard ecosystems. The Manion's decline disease spiral as a general model is proposed for fruit tree deline diseases. Control strategies in respect of the two ecosystems are discussed
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