Notes for first exam

Question 1

What does plant pathology include 1/4

Answer 1

Living entities and the environmental conditions that cause disease in plants

Question 2

What does plant pathology include 2/4

Answer 2

mechanisms by which these factors produce disease in plants

Question 3

What does plant pathology include 3/4

Answer 3

interactions between disease causing agents and the diseased plant

Question 4

What does plant pathology include 4/4

Answer 4

methods of preventing or controlling disease and alleviating the damage it causes

Question 5

We are dependent on plants for? 1/2

Answer 5

Food, feed feed fiber, chemicals, building materials, paper, medicine, shade, beauty, and atmosphere

Question 6

We are dependent on plants for? 2/2

Answer 6

products are damaged, which results in loss of life or lifestyle

Question 7

Definition of plant disease as which is defined by Agrios

Answer 7

series of invisible and visible responses of plant cells an tissues to pathogenic microorg. or envi. factor results in adverse changes in form function or integrity of the plant and my lead to partial impairment, or death of the plant or its parts

Question 8

Disease is part of spectrum

Answer 8

ranges from healthy to dead; abnormal physiological process that harms the host

Question 9

How do pathogens cause diseases

Answer 9

-by diverting resources from plant
-blocking transport of food minerals and water through plant
-killing plant
-direct withdrawal of cell contents

Question 10

symptoms

Answer 10

visible expression of disease

Question 11

signs

Answer 11

physical presence of pathogen

Question 12

Etiology

Answer 12

study of the cause of a disease (may include the pathogen

Question 13

Epidemiology

Answer 13

study of populations in relation to disease

Question 14

plant productivity in africa and asia lost due to pests and pathogens

Answer 14

40%

Question 15

Plant productivity in developed world lost due to pests pathogens

Answer 15

20%

Question 16

losses are due to viral, fungal, and bacterial pathogens

Answer 16

1/3

Question 17

Theophrastus (370-286 BC

Answer 17

-greek philosogher
-first to write about diseases of trees, cereals, and legumes
-noted disease worse in low lying arease

Question 18

Who is considered as father of plant pathology?

Answer 18

Anton De Bary

Question 19

-1882 outlined set procedures to determine the cause of a disease

-initially developed for animal disease but also used for plant diseases

Answer 19

Robert Koch

Question 20

What is Koch’s poltulates 1/4

Answer 20

symptoms as well as the signs of the pathogen in the disease host are fcarefully described

Question 21

What is Koch Postulates 2/4

Answer 21

suspend pathogen is isolated from the disease host, grown in pure cultures and described or identified

Question 22

What is Koch’s Postulates 3/4

Answer 22

healthy host of the same variety and species is inoculated with the suspected pathogen; later observed for symptoms which must be identical to those initially described

Question 23

What is Koch’s Postulates 4/4

Answer 23

pathogen in re-isolated from the inoculated host and must be identical to the organims previously isolated

Question 24

-Brown spot rice
-bipolaris oryzae
-long wet monsoon season in 1943
-during ww2 india colony and japan controlled burma (closest to rice)
-2mil people starved in Bangladesh and west bengal

Answer 24

Great bengal famine

Question 25

We get disease epidemics when there is a change in the triangle, how?

Answer 25

1.introduction of a new host or host cultivar
2.introduction of a ne host and its pathogen
3.introduction of a new pathogen or change in the pathogen population

Question 26

How to identify Phytoplasma identification?

Answer 26

-symptoms
-graft transmission
-insect vector transmission
-electron microscope
-sensitivity to specific antibiotics
-pcr

Question 27

How to idenatify virus and viroid identification?

Answer 27

-symptoms
-transmission tests
-serological tests
-electron microscopy
-inclusion body examination
-electrophoreses (protein, dna,dsRNA
-hybridization
-pcr

Question 28

Parasite

Answer 28

anorganism that lives on or in another organism from which it obtains its nutrition

Question 29

Pathogenicity

Answer 29

ability of the parasite to interfere with essential functions of the plant qualitative

Question 30

Virulence

Answer 30

degree of pathogenicity of a pathogen, qualitative

Question 31

aggressiveness

Answer 31

measure of the severity or speed of disease over time in a pathogen population ; quantitative

Question 32

host range

Answer 32

plants or plant parts that can be infected by a partivular pathogen

Question 33

saprophyte

Answer 33

organism that obtains its food from dead organic tissue (necrotroph)

Question 34

obligate parasite

Answer 34

organism that grows and reproduces only on living hosts (biotroph)

Question 35

non-obligate parasite

Answer 35

can utilize both living or dead hosts

Question 36

facultative saprophyte

Answer 36

parasites that usually live on a living host but can survive on dead organic matter

Question 37

facultative parasite

Answer 37

parasites that usually live on dead organic matter but can attack living tissue

Question 38

biotrophic fungi

Answer 38

-cant survive outside the living host
-cant usually be grown in vitro
-dont usually kill the host
-use haustroia to otain nutrients from the host
-narrow host range

Question 39

necrotrophic fungi
(facultative parasites and facultative saprophytes)

Answer 39

-have wide host ranges
-usually produce toxins or enzymes
-kill plant cells (live saprophytically on dead tissue
-can survive outside the host
-can often be manipulated genetically
-penetrate through natural openings or wounds
ex. fruit rot,leaf spots