Genetic control of Pest
refers to various methods by which a pest population is in theory or practice controlled by manipulating its genetic component or other inheritance mechanisms.
Sterile insect technique
The most widely used technique under this control method is
Sterile insect technique
The procedure involves mass-rearing insects, subjecting them to sterilization by irradiation or chemical mutagens, and releasing large numbers of males to mate with wild females
genetic mutations and chromosomal breaks that make them sterile
The radiation will cause
tris-(1-aziridinyl) phosphine oxide
is a chemical sterilant used in SIT. Insects are lured into traps containing this compound
is mutagenic and carcinogenic to man and animals
draw back of tris-(1-aziridinyl) phosphine oxide
Screwworm
in North and Central America
Mediterranean fruit fly
Florida
• tsetse fly, melon fruit fly, pink bollworm,
controlled by SIT
fruit fly
Queensland
methyl eugenol
as a lure for mango fruit fly
malathion
poison for mango fruit fly
Resistance
is the heritable property that enables a plant to inhibit pest population growth or recover from an injury caused by populations not inhibited from growing
ecological resistance and genetic resistance
two ways a plant becomes resistant to pest attacks
Ecological resistance
is considered a false resistance or pseudo resistance because it is under the primary control of the crop's environment.
Genetic resistance
is a right or real resistance because it is governed by resistance genes inherent to various introduced sources.
Phenological asynchrony
the crop's susceptible stage does not coincide with the pest population's peak such that the plant escapes the damage. In a real sense, the crop has no resistance to the pest
Silicon
usually increases the resistance of plants to insect feeding.
Cnaphalocrocis medinalis
Leaf Folder
Induced resistance
is brought about by the plants' proper care, such as fertilization and other farm practices that make them resistant to insect pest attacks
Antixenosis
occurs when a pest is less likely to find or feed on a resistant plant. It can be in the form of physical characteristics (such as dense hairs or a waxy surface) or chemical characteristics that deter feeding or disease infection
Antibiosis
occurs when feeding on a resistant plant harms the pest's health or fitness. In general, this is caused by chemicals in the plant tissue which can either directly kill, slow the development of, or reduce the reproductive capacity of a pest
Tolerance
occurs when a plant can continue to thrive despite being attacked. It does not decrease the likelihood of a pest to attack a resistant plant but rather indicates the tolerant plant's ability to continue to thrive despite being attacked
Disease resistance
is a property of the host which prevents damage by plant pathogens. It is also defined as the host plant's ability to exclude or overcome a pathogen's effect entirely or to some degree
Using of resistance variety
is perhaps the best pest control method for managing pest and disease problems
RC 216, 160, 300, 222
These varieties are high yielding and have resistance or moderate resistance to major pests and diseases like rice stemborer, brown planthopper, green leafhopper bacterial blight, and rice blast
IRRI
bred Rc 222
NSIC
release rice tungro disease resistant variety
Pathogen tolerance
is the host plant's ability to reduce the effect of infection on its fitness regardless of the level of pathogen multiplication so it can still have its normal yield despite the disease infection.
Pathogen resistance
is the host plant's ability to prevent damage by plant pathogens or the host plant's ability to exclude or overcome, entirely or to some degree, the pathogen's effect
Pre-formed resistance
• include structural barriers to penetration such as thick plant cuticle, waxy cuticle, partially closed stomates, lignified and suberized cell layers, corky cell layers, and pre-existing compounds
catechol and protocatechuic
acid in red onion scales
induced resistance
include active defense mechanisms to pathogen establishment. The pathogen induces these mechanisms upon infection. It also includes mechanical barriers, hypersensitive reaction, phytoalexin production, production of toxic metabolites against the pathogen, and detoxification of toxins produced by the pathogen
Mechanical barriers
production of gums, resins, and other exudates in response to pathogen invasion; and lignification and suberization of tissues in response to pathogen infection
Hypersensitive reaction
is the rapid localized death of host cells around the invading pathogen. It results in confinement and even death of the pathogen
Phytoalexin
are also produced when a plant exhibit HR
Systemic acquired resistance
A phenomenon in which plants infected with one pathogen become more resistant to subsequent infection by another pathogen
Plant defense resistance elicitors
The pathogens or parts of the pathogens that can induce plants' resistance are called
Cross protection
a mild strain of a virus when inoculated to a healthy plant can protect the plant from an aggressive strain of the same virus. The phenomenon is called
Chitosan
is another compound that can elicit resistance in plants. It has been found effective in inducing resistance of tomato to bacterial wilt, resistance in rice to bacterial blight and inducing resistance in abaca to bacterial heart rot.
salicylic acid, acetylsalicylic acid (aspirin), and dichloroisonicotinic acid
examples of plant defense activators
Agrobacterium tumeraciens
gene "gun," a bacterial "vehicle"
Gene gun
a chemical or electrical treatment (electroporation) inserts the genetic material into the host plant cell
Promoter gene
from a virus as part of the package to make the inserted gene express itself
crystalline toxin protein
injected to the Corn and cotton from the BT