FANNS 
VWum* Jt. Mumbf I 4 J 2001 
3 
Free-Living 
Nematodes 
Most nematodes are free-living, that 
is. not parasitic. They live in mud 
from mountain lakes to ocean 
bottoms and in all types of soils. 
They are among the most common 
creatures of the sea floor 
Eelworms and other plant 
feeders 
Many nematodes feed on plants. 
Some live outside the plant, pierce 
the plant wall and suc k out its juices. 
Other nematodes enter the plant 
itself There are some small enough 
to crawl through the stomata, or 
respiration pores, of leaves. Inside 
the plant they feed on the plant 
juices. The plant may wilt, or may 
form a lump called a gall. 
Eelworms are nematodes that do a 
lot of damage to the roots of plants 
such as potatoes. They find the 
plant roots in the soil by sensing 
chemicals produced 
by the roots. .**«- ... Some 
people say 
that leaving /jf 
m a r i g o I d a«l t 
plants among \f\ 
potato plants ( 
reduces the ^ii 
number of root 
nematodes. 
mtnwtaiks 
Nematodes and fungi 
A number of nematodes interact 
with fungi There are nematodes 
called vinegar eels, that live in the 
sediment of natural malt vinegar. 
The vinegar eels eat the food made 
by yeasts in the vinegar 
Certain nematodes use the hollow 
stylet in their mouth to inject 
bacteria into a fungus. The bacteria 
feed on the fungus, grow and 
multiply. The nematode rhen feeds 
on the bacteria. 
Nematodes even use fungi as a 
means of transport! The eggs of a 
nematixle that is a parasite in cattle 
pass from the host in the dung. A 
type of fungus grows on the dung. 
The young nematodes feed in the 
dung, then climb onto the fungi 
When the fungus releases its spores, 
the young worms are carried away 
with the spores. The nematodes 
land on plants some distance away, 
where they are swallowed by cattle 
to continue the cycle. 
Fungi, however, may fight back 
There are fungi that trap 
nematodes in their thread- 
like mycelium. Then the 
fungus eats the 
nematodes. .Scientists 
are trying to learn 
> whether these fungi can 
control nematodes that 
lanuge plant rcxHS. 
