Methods and Techniques in Nematology

Introduction

Ebrahim Shokoohi

Department of Biochemistry Microbiology and Biotechnology, University of Limpopo, Private Bag X1106, Sovenga, 0727, South Africa

* Corresponding author Dr. Ebrahim Shokoohi: Department of Biochemistry Microbiology and Biotechnology, University of Limpopo, Private Bag X1106, Sovenga, 0727, South Africa; E-mail: ???

Nematology is an important branch of biological science that focuses on the study of a diverse group of roundworms known as nematodes. In addition, nematology plays a crucial role in agriculture. It is integral to the management of crop pests and the enhancement of agricultural productivity through the study of nematode interactions with crops. Additionally, in the medical field, nematology is vital for controlling diseases caused by parasitic nematodes. Nematodes also serve as important bio-indicators of environmental health in environmental studies, offering insights into soil quality and ecological balance. These organisms can be found in virtually all environments around the world. The term nematode has its roots in Greek, deriving from the words nema and oides, which mean thread and resembling, respectively. Nematodes are an amazingly diverse group of organisms that can either be beneficial or parasitic to plants and animals alike. Generally, they have a slender body that is transparent and lacks segments, exhibiting bilateral symmetry. The study of nematology has made significant strides in the field of medicine. Notably, it has played a pivotal role in developing new antibiotics for the treatment of bacterial infections. Furthermore, nematology has been instrumental in identifying that tropical diseases like elephantiasis and ascariasis are caused by a type of nematode. Ascariasis is a parasitic infection caused by Ascaris. The disease occurs when individuals ingest food or water contaminated with the eggs of Ascaris species, typically found in soil, vegetables, fruits, and other foods. Research has revealed that Ascaris infections can potentially lead to impaired cognitive function in certain school-aged children. This underscores the importance of proper hygiene and food safety measures in preventing the spread of this disease. Several nematodes cause diseases in animals, such as fish, where they reduce the quality of the meat and pose a risk to food security. Nematodes are a type of parasite that can infect various types of fish in freshwater, marine, and brackish water environments. Some nematodes can have devastating effects on wild fish populations, leading to significant fish mortality. These parasites can infect fish in their adult stage, but their larval forms can also infect fish species after passing through birds, mammals, or reptiles that consume fish, or even through predatory fish. Certain nematodes, like Anisakis,

are zoonotic, meaning they can be transmitted to humans. Consumption of raw/undercooked infected fish meat poses a risk of infection to humans. Nematodes also pose a threat to the economic value of fish due to consumer concerns about their presence in food products. Infected fillets are often rejected, leading to increased production costs. Therefore, research on nematology brings valuable insight into the fish/animal parasites aiming to secure food.

In agricultural research, nematology plays a crucial role in providing a wide range of ecosystem services that have a significant impact on the nitrogen cycle, the ability of soil to decompose waste, and the control of pests within soil systems. Although, certain female plant-parasitic nematodes can take on a spherical shape, such as cyst and root-knot females. All plant-parasitic nematodes possess a stylet in their anterior end that helps them to pass the food through the plant cells to their body. This feature enables plant-parasitic nematodes to inject the enzymes into plant cells, which digest the food and help nematodes to develop and cause damage to plant cells. Plant-parasitic nematodes pose a significant threat to various plant types, including vegetables, trees, turfgrass, and foliage plants. They can cause extensive damage and significantly reduce crop yield. Root-knot, cyst, root lesion, spiral, burrowing, bulb and stem reniform, dagger, bud and leaf, and pine wilt disease are among the most harmful nematodes. These pests are responsible for an average loss of 12.3% annually in 40 major crops worldwide, with developing countries bearing the brunt of the losses, estimated at 14.6%, compared to 8.8% in developed nations. Plant-parasitic nematodes result in global economic losses of nearly $125 billion per year, affecting all agricultural crops. The impact of harmful nematodes on agricultural production is regularly undervalued, as their symptoms are frequently mistaken for other issues such as water stress, nutritional disorders, virus infection, soil fertility problems, or complex diseases caused by interactions of fungal/bacterial with nematodes. The severity of their impact depends mostly on the population density in the soil and roots, the cultivar susceptibility, and the ecological circumstances. Root-knot and cyst nematodes are the main destructive plant-parasitic nematodes. The implications of these misinterpretations can be significant, as they can lead to the implementation of inappropriate corrective measures, resulting in further damage to crops and reduced yields. Therefore, an accurate diagnosis of nematode infestation is critical in ensuring optimal agricultural productivity and profitability. To achieve this, it is essential to utilize appropriate diagnostic techniques to differentiate nematode symptoms from those of other conditions. This approach can help farmers and agricultural experts make informed decisions regarding the management and treatment of nematode-infested crops, ultimately leading to better outcomes for all involved.

On the other hand, beneficial or free-living nematodes play a critical role in soil health due to their contribution to soil nutrition, nitrogen fixation, and microbial balance. The soils in a hectare of all agroecosystems typically contain billions of both plant-parasitic and beneficial nematodes, which can significantly affect crop yields. In conclusion, nematology discipline is an attractive and principal field of study that plays a vital role in understanding the complex relationships between nematodes, plants, humans, animals, and their environment.

REFERENCES