GroveStudies Production:
Plant pathology or phytopathology (python - plant pathos - Ailments logos - knowledge)
Is that a branch of agriculture botanical and biological science which deals with cause etiology resulting losses and management of diseases.
Terminology :-
Disease and disorder :-
these two term carry the same meaning malfunctioning in the plant body however while the term disease include all types of harmful physiological changes in plant often the non infectious plant diseases due to abiotics causes such as adverse soil condition or terms disorder.
Pathogen:-
in a literal sense a pathogen is any agent that cause pathos , Ailments suffering or damage.
Include all living organisms associated with the disease viruses as well as abiotic agent such as adverse atmosphere or soil conditions.
Parasite:-
organisms which the material they need for growth from living plant (the host or the suspect) are called parasite.
Biotrops:-
Aur Nigam switch regardless or is with which they can be cultivated on artificial media always obtained their food from in nature from living tissue on which they complete their life cycle are called biotrops or obligate parasite.
Saprophytes:-
Organisms which derive their nutrition from that organic matter.
Parasite and saprophyte mein have their faculty to change their mode of nutrition.
Immune :-
Immunity of a plant against a given disease is an absolute quantity denote that the pathogen cannot established parasitic relationship with the host.
Tolerance:-
it is a type of defence that minimise crop loss without restricting disease development.
Concept of healthy plants:-
The ability to carry out normal physiological function at an acceptable level consistent genetic potential.
Disease is a mal functioning process in plant body caused by continuous irritation by some agent which result in some symptoms production.
It is a some total of altered and induced by chemical reaction in plant system are brought about biotic mesobiotic or abiotic leading to malfunctioning or physiological process and ultimately manifesting at cellular.
Pathogen:- any agent or entity which can induced disease in plant example fungi, bacteria, virus, viroids.
How pathogen effect plants :-
By utilising host contents.
By killing host or by interacting with metabolic process through their enzyme, toxins etc.
By weakening the host due to continuous loss of nutrient by interfering with the translocation of food, materials and water.
Note :-
Estimate annual loss worldwide :-
Loss and percentage
Diseases 14.1%
insect 10.2%
weed 12.2%
total annual loss 36.5%
Out of that losses diseases can be divided into two types
direct losses
indirect losses
Direct losses :-
Yield losses
post harvest losses
human health hazard.
Indirect losses:-
cost of pesticide.
and input for disease management.
History
Theoperators 370 to 286 BC he write a book initiated enquiry into plant.
He wrote the observation regarding in this book.
Following are the books where the description of plant diseases have been given :-
Rigveda 3700 BC
ArthraVeda 1500 to 500 BC
VishnuPurana 500 AD
Agni Purana 500 to 700 AD
virakshVeda 19th century by suryapal
Development of plant pathology:-
In in 1675 the dutchman Leeuwenhoek develop the first microscope and in 1683 he described bacteria seen with the this microscope.
In 1775 the French botanist till at published a paper on bunt or stinking smart of wheat now known as Tilletia Tritici.
John Needham (1749) observed the
appearance of organisms– concluded
that microorganisms originated from
meat.
M. W. Beijerinck (1898) – finally gave the term
virus named them as Contagium vivum
fluidum (Father of Virology)
Prove that tobacco mosaic disease was not caused by microorganisms rather it or originate from contagenium , vivum,fluidum which is later called Virus.
Beijerinck, in 1898, was the first to call 'virus', the incitant of the tobacco mosaic.
