6: Potatoes and Late Blight Flashcards
What family does the potato plant (Solanum tuberosum) belong to?
The Solanaceae (nightshade) family.
What toxic alkaloid is found in the above-ground parts of potatoes?
Solanine
What part of the potato plant is edible and what structure is it?
The tuber, an underground starch storage structure with “eyes” (buds)
What is chuño and why was it important in the Andes?
Freeze-dried potatoes made through freeze-thaw cycles and pressure; vital for long-term storage in high-altitude environments.
How did grain agriculture differ from potato agriculture in 17th–18th century Europe (2 key ways)?
Grains used fallow years and had long storage; potatoes used fallow land but required more weeding and had limited storage time.
What is a biotic plant disease?
A disease caused by living organisms (e.g., parasites) on or in a host.
What is an example of a biotic plant disease in potatoes?
Late blight caused by Phytophthora infestans.
Why are oomycetes considered “fungal-like organisms”?
They grow filamentous hyphae and produce spores, but differ from true fungi (e.g., undivided hyphae).
How can Phytophthora infestans spread between potato plants (2 ways)?
- Via swimming zoospores in moist soil
- by wind-dispersed spores.
What were two major social consequences of the Irish potato famine?
About 1 million deaths and 1 million people emigrated, mainly to North America.
What was the first method developed to control late blight?
The Bordeaux mixture (copper sulfate + lime) in the 1880s.
What is the modern method for controlling late blight?
Use of chemical fungicides introduced in the 1950s and beyond.
What is the main function of starch in plants?
Energy storage.
What are the two types of starch in potatoes?
Amylopectin (branched)
amylose (unbranched).
What are “seed potatoes” and why are they important?
Disease-free certified tubers used to prevent spread of late blight and ensure crop health.
What is the genus and family of the potato?
Solanum (genus),
Solanaceae (family).
What is a rhizome?
A horizontal underground stem that can produce shoots and roots.
What are zoospores?
Motile, flagellated asexual spores produced by oomycetes.
What does “fallow” mean in agriculture?
Land left unsown to restore soil fertility or rotate crops.
What is solanine and where is it found?
A toxic alkaloid found in green parts of the potato plant (leaves, stems, sprouts).
