Maximum Yield Australia/New Zealand May/June 2019 | Page 80
How to Get Rid of Harmful Nematodes
The first parasitic plant nematodes were noted in wheat seeds in 1743,
followed by root knot nematodes on cucumbers in 1855, and cyst nematodes
on sugar beets in 1859. By the early 1900s, the field of agricultural nematology
had taken root. Nematodes were first treated by soil fumigation in the 1940s,
however, most nematicides are now strictly regulated or banned due to their
harmful effects on the environment.
Nematodes may not move more than a metre in their lifetime, but they
can travel long distances in a variety of ways. They can be carried on
shoes, farm tools and equipment, in dirt that is moved, in water during
floods, and on plants and seeds. Dried nematodes in their dormant state
can even be carried in the wind. These modes of travel make it challenging
to quarantine and kill nematodes, so the best option is to manage their
populations as best we can in our gardens.
Follow Proper Sanitation Practices
Because of the way nematodes can travel, it is important to follow proper
sanitation practices. Be sure to clean farm equipment, tools, shoes, and
clothing when moving from field to field, or garden to garden.
When bringing in new plants, be sure to quarantine them for a short time
to make sure they are healthy before introducing them to your garden.
You can also check their roots for knots and lesions before transplanting.
Bringing sick or infested plants into your garden is one of the most common
ways to spread pests and disease. This raises a great argument for starting
your own plants from seed.
“BRINGING SICK OR
INFESTED PLANTS
INTO YOUR GARDEN
IS ONE OF THE
MOST COMMON
WAYS TO SPREAD
PESTS AND
disease.”
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Maximum Yield
Crop rotation is an effective
way to manage nematodes.
By planting non-host plants
in alternating years, you can
decrease their populations.
Cauliflower, broccoli, and
millet are ideal. French dwarf
marigolds and common vetch
are effective when used as a
cover crop and then turned
into the soil. Growing non-host
plants for two years in a
row will significantly lower
nematode populations.
You can also plant nematode-
resistant varieties. For
example, many tomatoes are
nematode-resistant, such
as Best Boy, Big Beef, French
Rose, Lemon Boy, OG 50,
Sugar Snack, Supertasty,
and Winter Red. Your seed
catalogs should be able to
point you in the right direction.
Neem oil kills parasitic
nematodes without harming
beneficial nematodes. Neem
oil works by disrupting their
growth cycle, which will
prevent them from laying
eggs before they die off. Neem
won’t harm most beneficial
insects, such as bees, and is
also an effective fungicide
and insecticide ideal for
preventative use.