The Impact of Climate Change on the Occurrence of Diseases and Pests of Agricultural Plants and Forest Trees

Abstract

The effects of climate change on harmful organisms are complex because other factors of influence are not constant, but are changing. In addition, climate change can affect harmful organisms differently or similarly, depending on which group of organisms they belong to: fungi, bacteria, viruses, insects, nematodes, etc. In fitopathogenic fungi, these effects are manifested in terms of: changes in biology; faster evolution due to longer seasons of the year; the emergence of new races or greater aggressiveness of existing species due to gene recombination; changes in geographical distribution, either towards the northern hemisphere or in areas of higher altitude; introduction of quarantine and invasive species, as well as expansion into new areas in relation to the area of origin; higher mycotoxin production; etc. For viruses and bacteria, which are transmitted by vectors, the impact of climate change on the presence, spreading and number of vectors is of special importance. The positive impact of climate change on different pests can be manifested in the form of: changes in biology and emergence of a higher number of generations; increased numbers and fertility; better overwintering; extended range of hosts; introduction of quarantine and invasive species; spreading to new areas; etc. The positive effects of climate change on harmful organisms are most often with a negative effect on the development of agriculture and food production, forestry development, biodiversity and the environment – due to possibility of greater economic damage, as well as greater needs for pesticides. Climate change can also affect host plants, with their loss of the natural basis of resistance being of particular importance. Although some progress has been made in monitoring and understanding climate change, there is still a need for many scientific, technical and institutional solutions to precisely plan, adjust and alleviate the effects of climate change on harmful organisms and hosts, as well as their interaction.