Exam 1

Question 1

Chlorosis

Answer 1

Yellowish coloration of plant tissue

Question 2

Interveinal chlorosis

Answer 2

The tissue between the veins is chlorotic and the veins remain green

Question 3

Vein clearing

Answer 3

Veins become translucent and the rest of the leaf is green

Question 4

Mosaic

Answer 4

Leaves have green to yellow patches with sharp edges

Question 5

Mottling

Answer 5

Leaves have green to yellow patches with mottled edges

Question 6

Symptoms of Plant Disease

Answer 6

1. Abnormal coloration of host tissues
2. Wilting
3. Death of tissue
4. Defoliation and fruit drop
5. Abnormal growth or replacement of host tissue

Question 7

Plant Pathology

Answer 7

• causes of plant disease
• mechanisms by which these factors cause disease
• interactions between plants and the causal agents of disease
• methods to prevent or control disease

Question 8

Plant Disease

Answer 8

A harmful alteration of the normal physiological and biochemical development of a plant caused by a pathogenic agent ore environmental factor.

Question 9

Causes of Disease

Answer 9

1. non infectious-Abiotic, environmental

2. infectious-Biotic

Question 10

Plant-microbe interactions

Answer 10

relationship between plants and pathogen

Question 11

causal agent

Answer 11

whatever it is that cause disease

Question 12

disease etiology

Answer 12

interactions between plant ant the pathogen in terms of ecology, life cycle and how it spreads.

Question 13

Major causes of plant disease (Causal agents)

Answer 13

• Fungi
• Bacteria
• Mollicutes
• Viruses
• Viroids
• Nematodes
• Parasitic higher plants
• Protazoa
• Mycoplamas

Question 14

Symptoms of plant disease

Answer 14

1. Abnormal Coloration of Host tissues
2. Wilting
3. Death of tissue
4. Defoliation and fruit drop
5. Abnormal growth or replacement of host tissue.

Question 15

Chlorosis

Answer 15

Yellowish coloration of plant tissue

Question 16

interveinal chlorosis

Answer 16

the tissue between the veins is chlorotic and the veins remain green

Question 17

veinclearing

Answer 17

veins become translucent and the rest of the leave is green.

Question 18

mosaic

Answer 18

leaves have green to yellow patches with sharp edges

Question 19

mottling

Answer 19

leaves have green to yellow patches with diffuse edges.

Question 20

lesions

Answer 20

localized injury to plant tissue, usually seen as leaf spots.

Question 21

necrosis

Answer 21

death of plant tissue, usually dark brown or black in color.

Question 22

rotting

Answer 22

decomposition of plant tissue, may be either dry or soft rot

Question 23

canker

Answer 23

necrotic areas in twigs, branches or stems which are often sunken

Question 24

mumification

Answer 24

dry shriveled fruit caused by fungal colonization

Question 25

hyperplasia

Answer 25

increase in the number of plant cells

Question 26

hypertrophy

Answer 26

increase in the size of plant cells ( these may lead to gall formation or twisting and curling of leaves and stems)

Question 27

host tissue replacement

Answer 27

the complete or partial replacement of host tissue by the pathogen.