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Oguh et al.; AJBGE, 2(3): 1-18, 2019; Article no.AJBGE.53356

for organic gardens must meet certain criteria set environmental factors that promote to the pests
forth by the United States Department of and their ability to thrive are ideal options [9].
Agriculture (USDA) and bear a logo stating they While the term pesticide is now often associated
are certified for use. The benefits of using with synthetic chemical compounds, it was not
organic or natural pesticides for plants are their until relatively recently that synthetic pesticides
specific target range, a slow mode of action, came into use. Naturally occurring compounds or
shorter persistence, low residue levels and safe natural extracts have been used as pesticides
use than conventional or synthetic pesticides [5]. since ancient times. The earliest pesticides were
These attributes are a win-win for consumers most likely salt, sulfurous rock, and extracts of
and the earth alike, but strict attention to time tobacco, red pepper, and the like. The
and mode of application and the precautions napoleonic army used crushed chrysanthemums
have to be strictly followed. That doesn’t mean to control lice, with limited effectiveness [10].
they are free from chemicals, just that the
chemicals are derived from botanical and mineral Natural insecticides can be chemical, mineral,
sources. They must still be used carefully, but the extract or biological. The common goal of all
chemicals break down more quickly than these is to kill, repel, or otherwise interfere with
commercial sources and are deemed less the damaging behavior of insect pests. Because
threatening [6]. this purpose corresponds with the legal definition
of a pesticide, all-natural insecticide products
The recognized categories of bio-rational must comply with federal and state regulations
pesticides may be synthetic or natural for registration, sales, transport, use, storage,
compounds of microbial, plant protectant and and disposal. Some natural insecticides are
biochemical (pheromones, hormones, natural allowed for use in certified organic systems if
growth regulators and enzymes) origins. Most additional organic federal standards are met [11].
biopesticides are nerve poisons acting at specific However, it is advisable to read the label of each
target sites in the insect's nervous system. Some product for specific application instructions. Many
pesticides act similarly to the old nerve poisons of the products described may also be used in
that result in knock-down, rapid intoxication, lack commercial crop production, but do not represent
of coordination, paralysis and death, and have the entire list available to commercial growers.
higher affinity to insect receptors than to As with any pesticide, it is important to choose a
mammalian. The other pesticides affect specific natural insecticide that fits the situation in which
systems, such as the molting processes, you will use it. These products vary in their
metamorphosis and the pest endocrinology toxicity to non-target organisms such as fish and
system. Biopesticides are third-generation bees, as well as their effectiveness at controlling
pesticides that are environmentally friendly and specific insect pests. If used improperly, organic
closely resemble or are identical to chemicals insecticides can harm people and the
produced in nature. The examples of environment, so do not make the mistake of
biopesticides are the microbial pesticide Bacillus thinking that products labelled as “natural” are
thuringiensis (Kurstaki), Most of the biopesticides non-toxic. There is a great effort to reduce the
show effectiveness against different strains of risk of human exposure to pesticides and special
resistant species, with no evidence of cross- demand for safe and more selective pesticides
resistance; hence these can play an important for natural enemies and non-target organisms.
role in integrated resistance management (IRM)
strategies [7]. 1.1 Definition of Terms

Most of the newer biopesticides are preferable to 1.1.1 Pest
the conventional pesticides because of their
specificity to target pests, effectiveness at low Pest is any harmful, destructive, or troublesome
rates, selectivity to beneficial insects and their animal, plant or microorganism.
non-persistent characteristics in the environment.
However, they are an alternative to the use of 1.1.2 Pesticides
conventional pesticides such as
organophosphates, organochlorine, Pesticides are chemical substance use to kill or
organosulphur, carbamates and pyrethroids [8]. retard the growth of pests that damage or
However, insect control using integrated pest interfere with the growth of crops, shrubs, trees,
management (IPM) means by use of several timber and other vegetation desired by humans.
techniques to reduce the favorable Practically all chemical pesticides, however, are

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