As a verb kill

is to put to death; to extinguish the life of.

As a noun kill

is the act of killing.

As an adjective necrotrophic is

describing a parasite that kills its host, then feeds on the dead matter.

As a noun host

is autumn (season).

As an adjective necrotrophic is

(biology) describing a parasite that kills its host, then feeds on the dead matter.

As adjectives the difference between saprotrophic and necrotrophic

is that saprotrophic is of or pertaining to saprotrophs (or saprobes) while necrotrophic is describing a parasite that kills its host, then feeds on the dead matter.

In biology terms the difference between strain and biovar

is that strain is a particular breed or race of animal, microbe etc while biovar is a strain of microorganisms that is physiologically and/or biochemically differentiable from others.

As nouns the difference between strain and biovar

is that strain is treasure while biovar is a strain of microorganisms that is physiologically and/or biochemically differentiable from others.

As a verb strain

is to hold tightly, to clasp.

As nouns the difference between microorganism and biovar

is that microorganism is while biovar is (biology) a strain of microorganisms that is physiologically and/or biochemically differentiable from others.

As an adverb physiologically

is in accordance with the science of physiology.

As a noun biovar is

(biology) a strain of microorganisms that is physiologically and/or biochemically differentiable from others.

As an adverb biochemically

is with reference to biochemistry.

As a noun biovar is

a strain of microorganisms that is physiologically and/or biochemically differentiable from others.

As an adjective differentiable

is having a derivative, said of a function whose domain and codomain are manifolds.

As a noun biovar is

a strain of microorganisms that is physiologically and/or biochemically differentiable from others.

As nouns the difference between cyclobutane and caryophyllene

is that cyclobutane is (uncountable|organic compound) a simple alicyclic hydrocarbon, c₄h₈; a light inflammable gas while caryophyllene is (organic compound) a sesquiterpene (containing a cyclobutane ring) found in the essential oils of several plants such as clove and pepper.

As nouns the difference between pharmaceutical and bioprospecting

is that pharmaceutical is (medicine) a pharmaceutical or pharmacological preparation or product; a drug while bioprospecting is (biology) the methodical search for novel pharmaceutical (and other) products from plants and microorganisms.

As an adjective pharmaceutical

is (medicine) of, or relating to pharmacy or pharmacists.