🪱 Important Nematodes

Root Lesion Nematode

• Pratylenchus sp.
• The generic name Pratylenchus was coined by adding first three letters from the specific name of the earlier described species Tylenchus pratensis as prefix to the generic name (Pra + Tylenchus).
• The common name – Lesion nematode is attributed to the characteristic symptoms produced on the roots.
• This group of nematodes is also commonly called Meadow nematodes since the first described species (T. pratensis) was recorded in meadows (grasslands) in Netherlands. Root lesion means जड़ का घाव.

  

• Root lesion nematode, Pratylenchus coffee is a serious pest of coffee in South India.
• Migratory endo parasite, feeding in root cortex of many plants. All stages are found in root or soil.

Rice Root Nematode

• Hirschmanniella sp.
• This generic name was coined in the honour of an eminent US nematologist, Dr. Mr. Hedwig Hirschmann.
• The common name, Rice root nematode is derived from its preference to rice and root parasitism.
• It cause Mentek/Omomentek disease of rice.

  

• Affected roots show discoloration and partially hollow. Therefore feeding adversely affects absorption of water and nutrients.
• Plants show stunted growth in patches with reduced tillering.

False root knot nematode

• Naccobus sp.
• It develops hypertrophy in the host.
• Its symptoms resemble to as root knot nematode like enlargement of cells.

  

Spiral Nematode

• Helicotylenchus sp.
• These nematodes have spiral or helical shape. (Helix = coil + Tylenchus)

  

Lance Nematode

• Hoplolaimus sp.
• Lance means a sharp or pointed weapon.
• Generic name Hoplo means arming + laimos means throat. A robust stylet is present in them.

  

Stunt Nematode

• Stunt or stylet nematode: Tylenchorhynchus sp.
• The name stunt nematode become popular with the stunting of tobacco.
• Greek word: tylos means knob + enchos means spear + rhynchos means snout.

  

Ring Nematode

• Criconema sp.
• It has large ring like annuli.

  

Sheath Nematode

• Hemicycliophora sp.
• Hemi means half + cyclio means rounded + phora means bearing.
• It bears sickle-shaped spicules.
• These usually called sheath nematodes due to the presence of additional cuticular sheath in females and juvenile stages.

  

Pin Nematode

• Paratylenchus sp.
• The members of this genus are the smallest plant parasitic nematode with size of < 0.5 mm.

  

Dagger Nematode

• Xiphinema sp.
• Word: Xiphidion means sword + nema
• Presence of characteristic sword like stylet.

  

• Xiphinema index transmits fan leaf virus of grape.

Needle Nematode

• Longidorus sp.
• Word: Longus = long + dorys = spear
• They possess long hypodermal needle like stylet.

  

Stubby Nematode

• Name because of characteristic symptom produced in infect plant i.e., stubby roots.
• Stubby – root nematode includes Paratrichodorus sp. and Trichodorus sp.

  

- Dropkin, V.H. 1980. Introduction to plant nematology. John Wiley and sons, INC. New York.
- Singh, R.S and Sitaramaiah, K. 1994. Plant pathogens. The plant parasitic nematodes. Oxford & IBH Pub. Co. Pvt. Ltd. New Delhi.
- Parvata Reddy, P. 1983. Plant nematology. Agricole Pub. Co., New Delhi.
- Southey, J. F. Laboratory methods for work with plant and soil nematodes Tech.
- Bull. Min. Agric. Fish. Food. Her Majesty’s Stationary Office, London.
- Walia, R. K and Bajaj, H. K (2014). Textbook of Introductory Plant Nematology. Directorate of Knowledge Management in Agriculture, ICAR, New Delhi. 
- Kumar, V., Khan, M.R. & Walia, R.K. Crop Loss Estimations due to Plant-Parasitic Nematodes in Major Crops in India. Natl. Acad. Sci. Lett. 43, 409–412 (2020). https://doi.org/10.1007/s40009-020-00895-2
- Figure 1: Source: A: Maggenti, 1981, B-E: Franklin, 1973