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What is a nematode

Nematode is an unsegmented "worm" that has elongated, rounded, and smooth body, pointed at both ends. Plant parasitic nematode has sharp mouthparts that are used to puncture the plant's cell walls, injects its saliva, and sucks out its contents.


Eggs are laid into an egg sac (around 300 eggs), either inside or outside the root tissues depending on the position of the female. The egg sac is a jelly-liked substance that protects the eggs from the outside environment. The eggs hatch within a few days or stay dormant in the soil or on decayed plant debris until the right climatic condition comes.

Juveniles are the young larvae. The larvae molts four times. During the second stage of larval development, they start to feed. They enter into the root tissues, usually through the root tips to select their feeding sites. Once settled, they start feeding. In the process, they release enzymes and hormones into the roots that cause abnormal cells' formation (galls or root knots) around their heads. Around 5 or more cells become enlarged to enormous sizes, which serve as their feeding sites. They feed on these cells by slightly moving their heads. At any time, they may leave the roots to infect other roots or may stay for life at their first feeding sites during the entire plant's growing season.

The adult males are usually worm-shaped while the females are pear-shaped. As they increase in size, the root walls often break- making them accessible to each other and allow the females to lay their eggs in the soil. The female nematodes can reproduce sexually but can also reproduce eggs without their male counterparts.

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