Mosquito
repellent action
of neem (Azadirachta indica) oil.
Sharma
VP, Ansari MA, Razdan RK.
Malaria
Research Centre, Delhi, India.
Two
percent neem oil mixed in coconut oil, when applied to the exposed
body parts of human volunteers, provided complete protection for
12 h from the bites of all anopheline species. Application of
neem oil is safe and can be used for protection from malaria in
endemic countries.
Neem
oil as a sand fly
(Diptera: Psychodidae) repellent.
Sharma
VP, Dhiman RC.
Malaria
Research Centre (ICMR), Delhi, India.
The
repellent action of neem oil was evaluated against sand flies
under laboratory and field conditions. Concentrations of 2% neem
oil mixed in coconut or mustard oil provided 100% protection against
Phlebotomus argentipes throughout the night under field conditions;
against Phlebotomus papatasi it repelled sand flies for about
7 h in the laboratory. Neem oil is an indigenous product and a
low-cost alternative for personal protection against sand fly
bites.
Field
studies on the
mosquito repellent action of neem oil.
Sharma
SK, Dua VK, Sharma VP.
Malaria
Research Center (Field Station), BHEL Complex, Ranipur, Hardwar,
India.
Repellent
action of neem oil was evaluated against different mosquito species.
2% neem oil mixed in coconut oil provided 96-100% protection from
anophelines, 85% from Aedes, 37.5% from Armigeres whereas it showed
wide range of efficacy from 61-94% against Culex spp. Therefore,
neem oil can be applied as a personal protection measure against
mosquito bites.
Publication
Types:
Clinical Trial
Controlled Clinical Trial
PMID:
8525409 [PubMed - indexed for MEDLINE]
Use
of neem oil as a mosquito repellent
in tribal villages of mandla district, madhya pradesh.
Mishra
AK, Singh N, Sharma VP.
Malaria
Research Centre (Field Station), Medical College Building, Jabalpur,
India.
A
field study was carried out to evaluate the mosquito repellent
action of neem (Azadirachta indica) oil in tribal forested villages
of District Mandla. Various concentrations of neem oil mixed in
coconut oil (1-4%) were applied to the exposed body parts of human
volunteers. Results revealed 81-91% protection during 12 h period
of observation from the bites of anopheline mosquitoes. Neem oil
is an indigenous product and a practical solution to curtail mosquito
nuisance.
PMID:
8936291 [PubMed - indexed for MEDLINE]
Neem affected Insects
Some
390 insect species are affected by neem extracts, including many
that are resistant to conventional pesticides. There is such a
complex interrelationship between the many components of the neem
compound that, to date, there has never been a recorded case of
developed neem resistance. This may not prove the case when refined
Azadirachtin products hit the market in the future. When man tries
to dilute and simplify natural phenomena, there are often unanticipated
consequences.
Neem products are medium to broad-spectrum pesticides of phytophagous
(plant-eating) insects. Most phytophagous insects are susceptible
to neem products, including those listed below.
ORTHOPTERA: The anti-feedant affect is particularly important
with this species. Several of this species will refuse to feed
on neem-treated plants for periods ranging from one to four weeks.
COLEPTERA: All beetles and weevils are sensitive to neem
products. The larvae of beetles refuse to feed on neem-treated
foliage. Some beetle larvae are actually killed on contact.
HOMOPTERA: Cicadas, leaf hoppers, aphids, scale insects
and psyllids display a varying response to neem extracts, eg planthopper
and leafhopper nymphs show considerable anti-feedant and retardant
effects, but scale insects show little response. White flies are
affected on some crops but not on others. Aphids often respond
to foliar treatments but are not good candidates for systemic,
soil-based applications. Neem also influences the ability of homopterous
insects to carry and transmit virus diseases. This may have particular
relevance with mosaic virus in cucurbits.
LEPIDOPTERA: Numerous field trials have confirmed the efficacy
of neem extracts in moths, fruit borers, corn borers, skippers,
mullers and butterflies. Neem acts as both a growth retardant
and anti-feedant in the larvae of most lepidopterous pests.
THYSANOPTERA: Thrip larvae in the soil are well controlled
with neem extracts, but there is reduced efficacy with heavy infestations
of adults on the plant. Neem oil has been more effective than
other formulations in controlling adult thrips, perhaps due to
an oil-related suffocation effect.
DIPTERA: Fruit flies, house flies, march flies, buffalo
flies and mosquitoes are all candidates for neem-based protection.
In Australia neem extracts have proven effective against blowfly
strikes on sheep and buffalo flies on cattle. Trials with the
dreaded Mediterranean fruit fly in Hawaii were particularly successful.
Spraying with diluted neem solutions under fruit trees resulted
in 100% control.
HETEROPTERA: The rice bug and green vegetable bug and other
juice suckers are affected by foliar and systemic neem treatments.
Both feeding behaviour and development are disrupted.
STORED PRODUCT INSECTS: Pest control in stored products
is one of the oldest traditional uses of neem in Asia. Traditionally
neem leaves are mixed with grain kept in storage. Repulsion seems
to be the principle mode of action here. Neem oil-treated sacks
prevent weevils or flour beetles from penetrating for several
months. Neem can also extend the storage life of potatoes by up
to three months.
