Homework SoursePlant parasitic nematodes attack many important agricultural
Plant parasitic nematodes attack many important agricultural crops resulting in millions of dollar in damage. In roots, injury by nematodes may be detected by the presence of lesions, cysts or galls/knots. Identify one genius of nematode that produces cysts, lesions and galls on an important agricultural crop in Ontario. List the crop and describe the damage.
Solution
Answer:
Nematodes are microscopic multicellular organisms that thrive in the soil and water. They are benificial for the ecosytem balance as they feed upon the organic matter and conver it into essential nutrients. Some epecies of nematodes are act as biocontrol agents for varoius plant pathogens such as bacteria, fungi and insects.
However, some nematode genus are act as plant parasite and tend to damage agriculture crops by damaging roots, stem and bulbs.
In different regions of Ontario, different agriculture crops are adversaly affected by several genus of nematodes. One of them is genus Heterodera which affect soybean crop and detected by the presence of lesions, cysts or galls/knots in roots.
Other crops are also affected by other nematode genus as given in the table below:
| Nematode | Crops | Damage |
| Heterodera sp. | Soybean , Sugarbeet, Oat | Cyst formation |
| Meloidogyne sp. | Soybean , Sugarbeet, Oat | Rootknot formation |
| Pratylenchus sp. | Soybean , Sugarbeet, Oat, Tomato, Onion | Root lesion formation, stunting and discolouration of roots |
| Ditylenchus | Onion, Garlic | Damage of bulb (bloating) and stem (twisting) |
