Resource Book on Horticulture Nursery Management

envisages that the responses may be as biofertilizer or by the control of some
undiagnosed plant pathogens.
Recently, Pseudomonas spp. is being promoted as plant growth promoting
rhizobacteria (PGPR). The mechanism of pathogen suppression by these bacteria
includes substrate competition, niche exclusion, and production of siderophores,
antibiosis and induced resistance.
Fungal Biopesticides:
Fungi unlike bacteria or virus do not require ingestion for infection; so sucking pests
are also targeted by primary contact or by secondary uptake from sprayed vegetation. The
pathogenesis begins with germination of conidia on the cuticle and penetration and
development inside the host leading to death of host essentially under high humid
condition.
Why Choose a Biopesticide?
� Human and environmental safety
� Alternatives to conventional pesticides
� Amenable to small-scale and local production in developing countries
� Increased public awareness of environmental and food safety
� Fundamental component of Integrated Pest Management
� Controls pests resistant to conventional pesticides
Biopesticides are pest management tools that are based on beneficial
microorganisms (bacteria, viruses, fungi and protozoa), beneficial nematodes or other
safe, biologically based active ingredients. Benefits of biopesticides include effective
control of insects, plant diseases and weeds, as well as human and environmental safety.
Biopesticides also play an important role in providing pest management tools in areas
where pesticide resistance, niche markets and environmental concerns limit the use of
chemical pesticide products.
Biological control is, generally, man’s use of a specially chosen living organism to
control a particular pest. This chosen organism might be a predator, parasite, or disease
that will attack the harmful insect. It is a form of manipulating nature to obtain a desired
effect. A complete Biological Control program may range from choosing a pesticide,
which will be least harmful to beneficial insects, to raising and releasing one insect to
have it attack another, almost like a “living insecticide”.
Popular Biopesticides used in Horticulture Nursery for Pest and Disease
Management
Microorganism
Insecticides
Target pest/disease
Bacillus thuringiensis (Dipel) Caterpillar, larvae
B. thuringiensis isrealensis (Acrobe) Mosquito, Black files
B. thuringienis tenebrionis (Novodor
)
Colorado potato beetle
B. thuringiensis aizawai (Certain) Wax moth, Diamond black moth
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