Plant Pathology

                                  Plant Pathology

PAT - DISEASES OF FIELD CROPS AND THEIR MANAGEMENT

Pathology

The term 'Pathology' is derived from two greek words 'pathos' and 'logos'.
'Pathos' means suffering and 'logos' means the study / to speak / discourse. Therefore if
etymologically means "study of suffering". Thus the plant pathology is the "study of
suffering plants". When the plant is suffering i.e. not developing and functioning in the
manner it is expected, then it is called as diseased. Due to this abnormality, the
productivity of the plant is reduced or lost.

Plant Pathology 

Phytopathology is one among the branches of agricultural science that deals with cause, etiology, resulting losses and management of plant diseases with four major objectives.

•  Study the disease(s) / disorders caused by biotic and abiotic agent(s)
• Study the mechanism(s) of disease development
• Study the interaction between plant and the pathogen in relation to the overall environment
• Develop suitable management strategy to surmount the diseases and to reduce the loss.
• Nature and concept of disease is very much varied. Many scientists proposed a number of definitions for a diseased plant. Anon (1950) defined the disease as "harmful deviation from normal functioning of physiological processes". According to Stakmann and Harrar (1957) plant disease is "a physiological disorder (or) structural abnormality that is deleterious to the plant / to any of its parts / products /that reduces their economic value". In general disease is an interaction among the host, parasite and the environment.

Histort OF Plant Pathology

The earliest known writings make references in the ravages of plant diseases. There
are references in the religious literature about the occurrence of plant diseases. Rigveda,
Atharveda (1500-500 BC), the Artha Shastra of Kautilya (321 -186 BC), Vishnu Puran
(500 AD), Agnipuran (500-700 AD) etc are some ancient books in which they have
mentioned the plant diseases and other enemies of plants along with the methods to
control them. The man in the Vedic period were aware of the fact that these diseases
are caused by microorganisms. Symptoms of plant diseases are also mentioned in Holy
Bible, Shakespear's poems and drama's. The early man considered the disease to be the
curse of God on man for his wicked deeds. The early man celebrated "Robigalia", a
special holiday during which they offered scarifies of red dogs and sheep in an attempt
to please the rust god "Robigo" and keep him from sending the rust disease to their
crop. Theophrastus, who lived from 370 BC to about 286 BC was the first scientist to
study and write about diseases of trees and cereals. He observed that certain plant
species are more liable to certain diseases than others. From the 5th century A.D until
the Renaissance, there was lack of intellectual activity and little was written on plant
pathological aspects. Ibn-al-aivam described the symptoms of many diseases of trees
and vines during 10th century AD. The period between 300 AD and 1300 AD is said to
be the middle / dark ages in the history

Reference

TNAU - Tamilnadu Agriculture University, Coimbatore Materials And TNAU - Affiliated Private College Materials, TNAU Government College Materials, ICAR - Indian Council Of Agriculture Research, New Delhi Materials to Collected.