Your morning coffee is in a perilous state. There are just two species of coffee plants on which the entire multibillion-dollar industry is based: One of them is considered poor-tasting, and the other, which you’re likely familiar with, is threatened by climate change and a deadly fungal disease.
Dan Saladino, a BBC journalist and author of the new book Eating to Extinction: The World’s Rarest Foods and Why We Need to Save Them…argues that the diversity of food is actually in decline. Of the hundreds of thousands of wheat varieties that farmers once cultivated, for example, only a handful are now farmed on a large scale…
As we grow and harvest fewer varieties of plants and animals, the foods you can buy in the grocery store may become less nutritious and flavorful, and — as the current state of coffee demonstrates — the global food system could become less resilient. That’s why it’s so crucial to lift up communities that are protecting foods from disappearing, Saladino told Vox in an interview about his new book.
RTFA. An interesting viewpoint and conclusion I don’t wholly agree with. But, hey, if Saladino is correct – even part way – we will be facing a new kind of food crop problem.
Eideard 
In the 1800s, Irish farmers became entirely dependent upon one type of potato–the Irish Lumper. This farming practice, called monoculture, contributed to a period of mass starvation and disease in Ireland from 1845 to 1852. https://soilsmatter.wordpress.com/2018/03/01/the-irish-potato-famine-could-it-happen-again/
Debate exists regarding nomenclature for the event, whether to use the term “Famine”, “Potato Famine” or “Great Hunger” (an Gorta Mór), the last of which some believe most accurately captures the complicated history of the period.
In any case, in Ireland between 1845 and 1855 about 1 million people died as many as 2.1 million fled the country.
The proximate cause of the famine was a potato blight which infected potato crops throughout Europe during the 1840s, causing an additional 100,000 deaths outside Ireland and influencing much of the unrest in the widespread European Revolutions of 1848. https://en.wikipedia.org/wiki/Great_Famine_(Ireland)
(FEB 9, 2022): ‘Spudpocalypse’ sparks potato shortage across US as disease and supply chain issues wreak havoc on spuds https://www.the-sun.com/news/4645388/spudpocalypse-potato-shortage-canada-massachusetts/
“In the matter of a potato wart (Synchytrium endobioticum) infestation located in the province of Prince Edward Island” The Canadian Food Inspection Agency 2021-11-21 https://inspection.canada.ca/plant-health/invasive-species/domestic-plant-protection-measures/potato-wart-order/eng/1637345349606/1637345350810
Oh no! I’m pretty much related to the whole eastern end of the island.
“Coffee is uniquely vulnerable to climate change. It grows in tropical regions, where temperatures and rainfall are becoming increasingly erratic; it is grown by small farms, which do not have the resources available to weather the coming literal and figurative storms; and despite the fact that coffee is among the most highly traded commodities in the world, little agricultural research time or money has been devoted to it.
Right now, just two species of coffee are grown commercially: Arabica and robusta. Droughts over the past couple of years have reduced coffee yield, even as demand is exploding. Something must be done. Tea plantations are facing similar problems, so switching to tea won’t help. https://arstechnica.com/science/2022/12/your-next-pour-over-may-be-liberica-or-excelsa/
See “The re-emergence of Liberica coffee as a major crop plant” https://www.nature.com/articles/s41477-022-01309-5