This document defines and describes different types of parasitism. It begins by defining a parasite as an organism that lives on or in another organism and obtains food for growth and reproduction. The main types discussed are ectoparasites, which live on the external surface of the host, and endoparasites, which live inside host cells or tissues. Other types include destructive parasites, which kill their host, and balanced parasites, which obtain nutrients without killing the host. Facultative parasites are normally saprophytic but can parasitize under conditions. Broad categories of parasitism include biotrophs, hemi-biotrophs, and necrotrophs/perthotrophs, which kill host

1. PARASITISM AND ITS TYPES
COURSE TEACHER
Dr. PARTHASARATHY S
Asst. Professor (Plant Pathology)
STUDENT : GOWTHAM M
ID. NO. : 2017021020
COLLEGE OF AGRICULTURAL TECHNOLOGY
(Affiliated to Tamil Nadu Agricultural University, Coimbatore-3)
Kullapuram (Po), Via Vaigai Dam, Theni-625 562

2. PARASITISM
An organism that lives on or in another organism and obtains
food from the latter for their growth and multiplication is
called parasite.
Broomrape Witchweed
© britannica © britannica

3. The word parasite is derived from a latin word ‘parasitus’ which means
“one who eats at the table of the another”
TYPES OF PARASITISM
Ectoparasite
Endoparasite
Destructive parasite
Balanced parasite
Facultative parasite
Facultative saprophyte

4. ECTOPARASITE
The parasite may live on the external surface of the host they
take nutrients from epidermal and mesophyll cells.
Erysiphe polygoni
© bladmineerders
EXAMPLE

5. The parasite may grow inside the host cell (intracellular) or in
between the cells (intercellular) of the host plant and draw
nutrition.
Leveillula taurica
They grow in the subcuticular cells parenchyma tissues or in
vascular tissues.
ENDOPARASITE
EXAMPLE

6. INTRACELLULAR
HYPHAE
INTERCELLULAR
HYPHAE

7. DESTRUCTIVE PARASITE
Those which draw nutrition from the host and often destroy or kill the
host.
Root rot, Wilt causing pathogens.
© arborjet

8. BALANCED PARASITE
Those which draw nutrition without killing the host.
© hiveminer

9. FACULTATIVE PARASITE
These are the organisms which are usually saprophytic in their mode of
life but under certain conditions they became parasites.
Pythium sp., Rhizopus sp., Fusarium sp., etc
© alchimiaweb
EXAMPLES

10. FACULTATIVE SAPROPHYTE
These are the organisms which are usually parasites in their mode
of life but under certain condition they become saprophytes.
Smut fungi, Phytophthora sp., Mucor sp. and Venturia sp.
© wikipedia
EXAMPLES

11. BROAD CATEGORIES OF PARASITISM
BY LUTTRELL (1974)
BIOTROPHS
HEMIBIOTROPHS
PERTHOTROPHS

12. BIOTROPHS
OBLIGATE INAPPROPRIATE
OBLIGATE PARASITE OR TRUE
PARASITE
Parasite only on/ in living host to complete their entire life cycle.
Plant cell remain alive.
Obligate parasite can be cultured in complex
artificial media.
Mildews
Viruses
Viroids
Candidatus Phytoplasma
EXAMPLES
Rust
Smut
EXAMPLES
© amienvironmental

13. HEMIBIOTROPHS
Pathogen only attack living tissues and continue to grow.
Further continue to grow and reproduce.
After the tissue is dead the plant cell remain alive initially
but killed later.
Cercospora
Alternaria
Helminthosporium
EXAMPLES
© flickr

14. PERTHOTROPH / NECROTROPH
Pathogen kill the tissue in advance of penetration
Live saprophytically.
Also, possess enzyme and toxin secretion.
Phytophthora
Agrobacterium
Sclerotium rolfsii
Claviceps
Venturia
EXAMPLES
© alamy

15. REFERENCES
ALICE D, JEYALAKSHMI C AND SETHURAMA K, 2007. HANDBOOK
OF INTRODUCTORY TO PLANT PATHOLOGY.
A.E.PUBLICATIONS,COIMBATORE.
https://www.britannica.com/plant/parasitic-plant/media/1511885/114207