Agriculture Reference
In-Depth Information
other pesticides such as neem products and
Bacillus thuringiensis
. Several
commercial products containing spinosad are available. Ensure the products
you use are registered for your crops, pests, and area.
Neem Products
Neem products are derived from seeds of the neem tree,
Azadirachta indica
,
for centuries, although serious research on them only began in the 1920s
in India and spread to other countries in about 1959. There are three basic
types of neem products: azadirachtin-based, neem oils, and neem oil soaps.
Neem oil is produced by crushing the seeds and extracting active ingredi-
ents using water or alcohol. The extraction and processing methods that
are used affect the oil's effectiveness as a pesticide, meaning not all neem
products are created equal. Although azadirachtin was thought to be the
primary pesticidal compound, it now appears likely that other chemicals in
the neem seeds also help protect crops. These compounds act like hormones
in insects, preventing juveniles from maturing into adults. They also reduce
insect feeding and egg-laying on treated plants.
In fruit crops, neem products have effectively controlled aphids (including
rosy apple and wooly apple aphids), leafhoppers, spotted tentiform leafminer,
and tarnished plant bug. It has partially controlled white apple leafhopper,
caterpillars, and mites. It has not performed well against beetles, psyllids,
and scales. Mixing azadirachtin-based and neem oil products has sometimes
produced better results than using the materials alone. Mixing neem oil and
neem oil soap products can cause phytotoxicity.
Pyrethrum Products
Pyrethrum products are derived from the dried flower heads of several spe-
cies of pyrethrum daisies. They are effective against a wide range of insects
and paralyze the insects by attacking their nervous systems. Pyrethrums are
especially known for knocking down insects quickly. Unfortunately, the in-
