Soil parasitic nematodes are a diverse group of microscopic roundworms that inhabit the soil and can have significant impacts on agriculture, including vineyards. These nematodes are found in almost all habitats, with a square yard of woodland or agricultural habitat potentially containing several million individuals. They are particularly abundant in marine, freshwater, and soil habitats, with some species causing economic damage to cultivated plants.
Types of Soil Parasitic Nematodes
Nematodes are classified into various orders within the Phylum Nematoda, with about 10 of these orders regularly occurring in soil. The orders Rhabditida, Tylenchida, Aphelenchida, and Dorylaimida are particularly common in soil environments. Based on their feeding habits, soil-inhabiting nematodes can be classified into several important groups:
- Herbivores: These plant parasites include many members of the order Tylenchida, as well as a few genera in the orders Aphelenchida and Dorylaimida. They use a needlelike stylet to puncture cells during feeding.
- Bacterivores: These free-living nematodes feed only on bacteria and are beneficial in the decomposition of organic matter.
- Fungivores: This group feeds on fungi, using a stylet to puncture fungal hyphae.
- Predators: These nematodes feed on other soil nematodes and on other animals of comparable size.
Impact on Vineyards and Agriculture
Nematodes are a major economic problem in every major grape production region in the world. They can cause direct damage by stopping root elongation, killing plant tissue, changing root growth patterns, and removing plant nutrients. Indirectly, they can damage plants by vectoring viruses or by increasing the severity of other plant diseases. Soil-borne parasitic nematodes cause severe deterioration in the health of crops and livestock, leading to enormous economic losses worldwide.
How to Take a Soil Sample
Taking a soil sample for nematode analysis involves several steps to ensure that the sample accurately represents the nematode population in the area of interest:
- Contact a Testing Laboratory: Before sampling, it's important to contact a testing laboratory to get the proper sampling procedure.
- Sampling Procedure: Collect soil samples from several locations within the vineyard or agricultural field to get a representative sample. The depth and amount of soil collected will depend on the laboratory's requirements.
- Handling and Shipping: Place the soil samples in a cool, dark place and ship them to the laboratory as soon as possible to prevent the nematodes from dying or changing state.
Conclusion
Soil parasitic nematodes play a significant role in agriculture, with both beneficial and detrimental effects. Understanding the types of nematodes present in the soil, their impacts on crops and vineyards, and how to properly sample the soil for analysis is crucial for managing these organisms. Sustainable management strategies, including the use of natural nematode enemies, are important for controlling nematode populations while minimizing environmental impact.
Citations:
[1] https://entnemdept.ufl.edu/creatures/nematode/soil_nematode.htm
[2] http://www.wine-grape-growing.com/wine_grape_growing/wine_grape_growing_chapters/ch23_managing_nematodes_vineyards.htm
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9229181/
[4] https://www.ars.usda.gov/northeast-area/beltsville-md-barc/beltsville-agricultural-research-center/mycology-and-nematology-genetic-diversity-and-biology-laboratory/docs/docs-nl/plant-parasitic-nematodes/
[5] https://grapes.extension.org/nematodes/
[6] https://pubmed.ncbi.nlm.nih.gov/35745494/
[7] https://eorganic.org/node/2527
[8] https://www.wineaustralia.com/growing-making/pest-and-disease-management/nematodes
[9] https://www.agric.wa.gov.au/nematodes/nematodes
[10] https://eorganic.org/node/4495
[11] https://www.canr.msu.edu/resources/nematode-parasites-of-grape-in-michigan
[12] https://en.wikipedia.org/wiki/Nematode
[13] https://vinehealth.com.au/media/Nematode-article.pdf
[14] https://www.certisbio.com/blog/soil-nematodes-good-bad-or-both
[15] http://www.wine-grape-growing.com/wine_grape_growing/managing_nematodes_vineyards/controlling_vineyard_nematodes.htm
[16] https://kare.ucanr.edu/programs/Nematodes/Nematode_overview/
[17] https://pubmed.ncbi.nlm.nih.gov/19270927/
[18] https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/plant-parasitic-nematodes
[19] https://winebusinessanalytics.com/news/article/69006/Nematodes-Threaten-Vineyards
