Difference Between: Plant Pathology

This series includes the difference tables between

  • Localized fungicide and Systematic fungicide
  • Localized infection and Systematic infection
  • Soil borne fungi and Seed borne fungi
  • Eradication and Crop rotation
  • Obligate parasite and Facultative parasite
  • Plant quarantine and Crop rotation
  • Nature culture medium and Synthetic culture medium
  • Primary inoculum and Secondary inoculum
  • Infection and Invasion
  • Pathogenesis and Pathogenicity
  • Symptom and Syndrome

Differences on diseases

  • Stem rust of wheat and Leaf smut of wheat
  • Wilt disease and Damping off disease
  • Blight disease and Blast disease
  • Penetration and Parasitism
  • Powdery mildew and Rust
Localized fungicideSystematic fungicide
It is protective in nature.It is therapeutic in nature.
Effective only in the plant area where it is applied.Absorbed and systematically translocated by plants.
They are externally functioning.They are internally functioning.
Restricted to a particular area.Involves the whole plant.
It is an older type of fungicide.It is not as old as protectants.
E.g. Copper fungicide and Bordeaux mixture.E.g. Carboxin.


Localized infectionSystematic infection
Localized infection is one that affects only parts of the body such as stem, leaf, root etc.Systematic infection is one that affects the entire body.
Protective in nature.Therapeutic in nature.
They are externally functioning.They are internally functioning.
Example: Tikka disease of ground nut.Example: Rust, smut etc.


Soil borne fungiSeed borne fungi
Associated with soil.Associated with seed externally or internally.
Dormant structure such as thickened hyphae and sclerotia are present.Dormant mycelium is present under seed coat or in the embryo (internal seed borne fungi).
Dormant spores (conidia, chlamydospore, oospore etc) are present in the soil.Dormant spores are present on seed coat (external seed borne fungi).
Depending on soil pH, moisture or other microorganisms of soil.Are not dependent on these.


EradicationCrop rotation
Eradication is the reduction of an infectious diseases prevalence in the global host population to zero.Crop rotation is the practise of growing a series of dissimilar or different types of crops in the same area in sequenced seasons.
It works against both soil and seed borne fungi.It works against soil borne pathogen.
It does not help in reducing soil erosion and also does not increase soil fertility and crop yield.It helps in reducing soil erosion and increases soil fertility and crop yield.
It does not increase diversity.It helps to increase diversity.
Successfully eradicated two diseases: Human smallpox, rinder pest.This method is followed for many crops such as legumes , root vegetables, leafy green vegetables etc.




Obligate parasiteFacultative parasite
They can’t complete their life cycle without the presence of host cell.They can complete their life cycle independent of their host.
They do not kill host tissue.They kill host tissue that they invade.
They are host specific.They are not host specific.
They don’t secrete toxic substances on host cell.They can secrete toxic substances to their host.
They are comparatively advanced from evolutionary point of view.They are primitive form evolutionary point of view.
E.g. Puccinia graminis-tritici, Ustilago hordei, Erysiphe sp.Example: Cercospora, Alternaria, Colletotrichum, Macrophomina etc.


Plant quarantineCrop rotation
Plant quarantine includes the regulations of the movement of living plant or plant products between politically defined territories.Crop rotation is the practise of growing a series of dissimilar or different types of crops in the same area in sequenced seasons.
It is not as old as crop rotation.It is one of the most oldest methods.
It is one kind of regulatory method of controlling plant diseases.It is one kind of cultural method of controlling plant diseases.
It follows some strict rules and regulations.This method have no specific rules and regulations.
Three important aspects of crop rotations are:
1. Inspection
2. Certificatin
3. Embargo.
Three important aspects of crop rotation are:
1. Reducing soil erosion.
2. Augmenting soil fertility.
3. Increasing soil diversity.


Natural culture mediumSynthetic culture medium
Natural media are composed of chemically undefined compounds.Synthetic media are composed of chemically defined compounds.
It consists solely of a naturally occurring biological fluids.Synthetic media are prepared by adding nutrients (both organic and inorganic).
The chemical composition of a natural medium is not properly known.The chemical composition of a synthetic medium is completely known.
It is less expensive.It is more expensive.
The reproducibility rate, in case  of natural media is poor or not satisfactory.The reproducibility rate is comparatively high.
It can be of three types:
1. Biological fluid containing media.
2. Tissue extracts controlling media.
3. Clot media.
It can be of four types:
1. Serum containing media.
2. Serum free media.
3. Chemically defined media.
4. Protein free media.
Prepared for most common routine test.Prepared for special study.
Example: Vegetable extract, fluid juice.Example: Peptone martite agar medium.


Primary inoculumSecondary inoculum
An inoculum that survives dormant in the winter or summer and causes the original infection in the spring or autumn is called primary inoculum.An inoculum produced from primary infection is called secondary inoculum.
It develops from the perenating organ or comes from the neighbouring field.It develops after the functioning of primary inoculation.
Primary inoculum causes primary infection.Secondary inoculum causes secondary infection.
Primary inoculum starts the diseases.Secondary inoculum spreads the disease.
Example: Overwintering or oversummering pathogen or its spores that cause primary infection.

In Puccinia, the urediospore is the primary inoculum.

Example: Inoculum produced by infection take place during the same growing season.

In Puccinia, aeciospore is the secondary inoculum.


Infection is the process by which pathogen establish contact with the susceptible cells and tissues of the host and procure nutrients from it.Spreading of the pathogen into the host tissue is known as invasion.
Infection initiates invasion.Invasion is the process that starts after infection.
Types of infection regulate invasion process.It is a substage of infection.
Infection can be of two types:
1. Primary infection
2. Secondary infection
Invasion can be localized or systematic.






Differences on diseases

  • Stem rust of wheat and Leaf smut of wheat
  • Wilt disease and Damping off disease
  • Blight disease and Blast disease
  • Penetration and Parasitism
  • Powdery mildew and Rust

See the characteristics of the disease and make differences accordingly.

Stem rust of wheatLeaf smut of wheat


Wilt diseaseDamping off disease


Blight diseaseBlast disease




Powdery mildewRust


About Abulais Shomrat

Abulais Shomrat
Currently in 4th year (Hons) in Department of Botany, University of Dhaka. Planning to have multiple careers one by one but promised to be with 'Plantlet' as long as it's primary stage remains unfinished.

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