M7: Agricultural Infectious Diseases

Question 1

what are the factors affecting the incidence of infectious disease?

Answer 1

host factors, pathogen factors, environmental factors

Question 2

examples of host factors?

Answer 2

• susceptibility to disease, access to pathogens, weakened immunity, drought/heatwave stress

Question 3

pathogen factors?

Answer 3

• availability, transfer between hosts, adhere and invade host tissue

Question 4

environmental factors?

Answer 4

• overcrowding, lack of hygiene causing build-up of waste, reservoirs

Question 5

causes of fungi in plants?

Answer 5

• reservoirs in contaminated seeds, farm machinery, soil and weeds. These are transmitted by wind and water and enter via stomata and wounds.

Question 6

causes of bacteria in plants?

Answer 6

• reservoirs in soil, weeds and seeds. Transmitted on hands and equipment, and can only reproduce in warm weather, overcrowding, and bad soil

Question 7

the scientific name for Panama Disease of Bananas?

Answer 7

fusarium oxysporus fungi

Question 8

symptoms of Panama disease?

Answer 8

yellowing and wilting of leaves, splitting of stems

Question 9

how is Panama’s disease transmitted?

Answer 9

root-root contact and contaminated soil from shoes and machinery

Question 10

Biological effects of infectious diseases in plants?

Answer 10

• wilting, destruction of tissue, loss of conducting tissue, abnormal growth

Question 11

social and economic effects of infectious diseases in plants?

Answer 11

• reduced agricultural yield
• loss of trading opportunities
• economic loss for farmers

Question 12

what is endemic?

Answer 12

consistently present in a region

Question 13

what are exotic diseases?

Answer 13

introduced diseases

Question 14

what is epizootic?

Answer 14

animal equivalent of epidemic

Question 15

what is zoonosis?

Answer 15

disease that can be transmitted to humans

Question 16

what are the factors contributing to infectious disease?

Answer 16

• increased mobility of human populations
• the rise of intensive and industrial type agriculture
• changing patterns of land use
• climate change
• antimicrobial resistance
• pesticide resistance
• loss of genetic diversity
• increase in hobby farmers
• increase of aquaculture

Question 17

what is foot rot caused by?

Answer 17

bacterium Dichelo Bacter Nodosus

Question 18

where does foot rot occur and what are the symptoms?

Answer 18

1. overgrown hooves and some dermatitis between toes
2. painful abscessed between toes, lameness, weight loss (less grazing)

Question 19

how foot rot is transmitted?

Answer 19

spread foot-foot via moist water, pasture reservoirs