Impact of Climate Change on Soil Nematodes - Implications for Sustainable Agriculture

Nematodes by virtue of their trophic diversity occupy a central position in soil food webs and play an important role in providing vital ecosystem services. Acting directly as pests and indirectly as vectors of other plant pathogens and consumers of microflora and fauna, nematodes play a significant role in regulating plant growth, biological pest suppression and nutrient cycling in agroecosystems. Global warming resulting in elevated carbon dioxide (CO₂) and temperature in the atmosphere influence parasitic nematodes directly by interfering with their developmental rate and survival strategies and indirectly by altering host physiology. It may also influence free-living (microbial feeding) nematodes due to changes in quality and availability of food under enriched CO₂ conditions. Available information on effect of global warming on soil nematodes though limited, indicate that abundance of soil nematodes in general is either increased or unaffected by elevated CO₂ levels while individual species and trophic groups differ considerably in their response to climate change. Herbivorous nematodes showed neutral or positive response to CO₂ enrichment effects with some species showing the potential to build up rapidly and interfere with plant's response to global warming. Studies have also demonstrated that the geographical distribution range of plant and animal parasitic nematodes may expand with global warming spreading nematode problems to newer areas. These findings underline the importance of understanding the impact of climate change on soil nematodes and its implications to agricultural systems while developing mitigation and adaptation strategies to address impact of climate change on agriculture.