Food & Climate
Climate change exacerbates food crises, and is a driver of world hunger. This could threat repeating potato famine scenario in some world’s places; how can we avoid?
Bioengineering can help protect crops from extreme weather and pests. Climate change is making this more important than ever, but controversy and underfunding make crop-breeding a challenge, according to a report seen by “Food & Climate” platform.
The Irish Potato Famine, also known as the Great Hunger, began in 1845 when a mold known as Phytophthora infestans caused a destructive plant disease that spread rapidly throughout Ireland.
The infestation ruined up to one-half of the potato crop that year, and about three-quarters of the crop over the next seven years. Because the tenant farmers of Ireland—then ruled as a colony of Great Britain—relied heavily on the potato as a source of food, the infestation had a catastrophic impact on Ireland and its population.
Before it ended in 1852, the Potato Famine resulted in the death of roughly one million Irish from starvation and related causes, with at least another million forced to leave their homeland as refugees, according to “History”.
Similar results
Climate change would cause similar results. As global temperatures and sea levels rise, the result is more heat waves, droughts, floods, cyclones and wildfires. Those conditions make it difficult for farmers to grow food and for the hungry to get it, according to “U.S. embassy & consulates in Italy “.
Researchers from North Carolina State University have studied the genetic material found in historic potato leaves in an attempt to understand the evolutionary changes that have occurred in both potato plants and the late blight pathogen since the Irish potato famine in the 1840s, according to “Hort news”.
The study used targeted enrichment sequencing to simultaneously examine both the plant’s resistance genes and the pathogen’s effector genes (which help it infect hosts).
“We use small pieces of historic leaves with the pathogen and other bacteria on them; the DNA is fragmented more than a normal tissue sample,” said Allison Coomber, an NC State former graduate student researcher and lead author of the paper.
“We use small 80 base-pair chunks like a magnet to fish out similar pieces in this soup of DNA to find resistance genes from the host and effector genes from the pathogen.”
The study’s results confirm that the pathogen, Phytophthora infestans, is very adept at fighting off potato late blight disease resistance.
The study also shows that many of the pathogen’s effector genes have remained stable, although different mutations have occurred to increase its infection prowess as plant breeders attempted to breed resistance – specifically after 1937 when more structured potato breeding programs commenced in the United States and other parts of the globe. The study also shows that the pathogen added a set of chromosomes between 1845 and 1954, the period of time in which the study’s plant samples were collected.
“We show in this work that after 100 years of human intervention, there are some genes that haven’t changed much in the pathogen,” Coomber said”.
Biotechnology can help
Matt McIntosh, the farmer and freelance journalist based in southwestern Ontario, at “The Narwhal”, said: “I believe biotechnology can help us better weather this uncertain future, but it will require time, money and attention by governments and businesses”.
Phytophthora Infestans is still a problem for potato growers. We have tools to protect our crops now, though, including fungicides and better crop varieties.
In 1998, for example, researchers with the United States Department of Agriculture developed a variety highly resistant to late blight, for use by public and private plant breeders.
More recently, the American company Simplot used biotechnology (rather than traditional plant breeding) to produce three varieties with high resistance to multiple potato diseases.
The last century has given us faster and more accurate ways to tinker. Mutagenesis — using radiation to mimic spontaneous mutation in the natural world — has been widely used. Transgenic technology (used to develop what are commonly called genetically modified organisms, or GMOs) can put beneficial genetics from one organism directly into the genome of another. Gene editing, the most recent scientific development, allows for highly precise changes within an organism’s existing genetic code.
The technological achievement underpinning it all is our ability to map an organism’s genetic code — to determine what genes are responsible for what traits. Knowing what gene is responsible for a tomato’s immunity to a specific insect pest, and breeding for it, could reduce insecticide use. Genetically improving gut health in cattle, sheep and goats could help reduce methane emissions.