Explanation

 heterozygous sickle cell anemia gives protection against malaria

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Heterozygotes are therefore more resistant to the debilitating effects of malaria than the normal homozygotes.

sickle cells are also resistant to malaria.

Heterozygotes are resistant to malaria

because of their recessive allele, but they lack sickle cell disease because of their dominant allele

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Explanation

First-generation pesticides included:

• organic
• and inorganic molecules.

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Second-generation pesticides were insecticides including:

• Dichlorodiphenyltrichloroethane DDT,
• chlorinated hydrocarbon,
• carbamates
• and organophosphates.

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Third-generation pesticides are far superior to the lead arsenate and DDT that epitomize the two earlier generations.

These chemicals are called juvenile hormones which are made in two small glands in insects' heads. 

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ND11-12-2022

Explanation

Cochineal insects are used for Cactus prevention

Cochineal insects are more effective in controlling small cactus plants.

It might be necessary to hand-fell large cactus plants

once they are heavily infested with cochineal,

and then leave the cochineal to kill the plant remnants.

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ND11-12-2022

Explanation

When a natural predator (living organism) is applied to the other pathogen organisms to control them, this process is called Biological control 

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ND11-12-2022

Explanation

Rotenone is a natural compound, used as an insecticide and a herbicide.

It is a commonly used pesticide and is also used in lakes and reservoirs to kill fish that are perceived as pests.

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ND11-12-2022

Explanation

Paecilomyces lilacinus is applied to soil to control nematodes that attack plant roots.

The fungus attacks the nematode through hyphal penetration.

Paecilomyces lilacinus is a naturally occurring fungus found in soils throughout the world.

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ND11-12-2022

Explanation

Trichoderma species promotes the growth of plants and limit the growth of plant pathogens.

Trichoderma species are effective bio fungicides,

enzymatically degrading other fungi,

producing anti-microbial compounds that kill pathogenic fungi,

and out-competing pathogenic fungi for space and nutrients.

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ND11-12-2022

Explanation

Xanthomonas campestris is a gram-negative bacterium that causes black rot, the most important disease of vegetable crops.

It is not used as a biopesticide.

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ND11-12-2022

Explanation

Biocontrol agents or microbial antagonists prevent infection of the host plant by the pathogen, or establishment of the pathogen in the host plant

The biocontrol fungi, Trichoderma spp., are not only able to control the pathogens causing plant disease,

but can also induce seed germination, and seedling emergence and promote plant growth

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ND11-12-2022

Explanation

Trichoderma species are widespread filamentous fungi in soils, on plant roots, and on decaying plant residues.

Due to their strong competitiveness and mycoparasitic activity against other fungi.

particular strains of Trichoderma sp. are used in agriculture as biocontrol agents against plant pathogens

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ND11-12-2022