To celebrate International Carrot Day, we take a closer look at the multi-country effort in which researchers are developing carrots to withstand a changing climate.
Carrots are tasty, versatile, and – while your tomatoes and cauliflowers go all squishy – easy to store for a long time. Most importantly, carrots are packed with micronutrients, especially the precursor of Vitamin A.
“Half a carrot a day is enough to meet an individual’s need for Vitamin A,” says Philipp Simon, USDA/ARS Research Geneticist and Professor for Horticulture, University of Wisconsin-Madison.
Vitamin A deficiency weakens immune systems, making diarrhea and measles deadly diseases, and can even lead to blindness. There are some shocking statistics from the World Health Organisation (WHO), which estimates that 250 million preschool children are deficient in the vitamin, leading to half a million children going blind per year, half of whom die within a year of losing their sight. All of which is completely preventable. “A plot of land a square meter in size could provide all the Vitamin A needed for two adults, for a whole year,” says Simon.
But to eat half a carrot a day you need access to carrots. And to have access to carrots, someone must grow them – which is becoming far harder to do in an increasingly unpredictable climate. To grow carrots, you need loose and well-watered soil. In many places, soils are becoming drier and saltier, even in parts of the world that can afford high-input farming systems, such as the United States.
A few years ago, there wasn’t much demand in the United States for carrots adapted to climate change,” says Phillip. “That’s changed, particularly now that there has been a four-year drought in California, where most US carrots are grown.
Philipp is leading a multi-country project in which scientists are exploring the genetic diversity found in the wild relatives of the domesticated carrot, and using it to develop carrots better adapted to hotter, drier and more saline conditions.
“Some wild carrots are surviving in very harsh conditions without any human intervention,” Philipp says. “That’s a good sign, it tells us they have developed traits which make them more tolerant to heat, drought and salt. We can use that genetic variation to improve the commercial crop,” says Philipp, who has worked in carrot genetics for almost 40 years.
The carrot project is one of 19 pre-breeding efforts that the Crop Trust is funding under its 10-year Crop Wild Relatives Project. For this project, researchers from Bangladesh, Pakistan, India, Taiwan and the US have teamed up to first characterize selected wild carrots for stress tolerance in extreme field conditions, then cross the most tolerant ones with a range of preferred local cultivated varieties. In short: flavor meets stress tolerance.
“Yes, that’s exactly what we are trying to do,” says Abdur Rahim, Professor at the Bangladesh Agricultural University. “In fact, this is the first project using crop wild relatives for the stress areas of Bangladesh.”
“In Bangladesh, carrot is a new crop,” adds Rahim. “Demand is increasing day by day.”
Unfortunately, yearly monsoons blow the salty water of the Bay of Bengal inland. Ten percent of the land is affected by salinity, and about 15 percent of Bangladesh is in a drought and heat stress area. So production is finding it difficult to keep up with demand.
As the demand for carrots is high all over Bangladesh, we need good varieties to grow in stress areas,” says Abdur Rahim, Professor at the Bangladesh Agricultural University.
Case in point: Satkhira is in the South of Bangladesh, on the Bay of Bengal, and the field sites of the project are swamped with salt. In most growing seasons, soil salinity levels are about triple what your average carrot crop can handle. But, amazingly, some of the wild carrots survived these harsh conditions.
At the other end of the Himalayas, in Pakistan, carrots are already more established, with the red carrot variety ‘T-29’ being essential for many traditional Pakistani dishes. However, Pakistan’s carrot yield is much lower than its potential; it has even been declining over the past 20 years.
“We are using plants that have been found to be tolerant to heat, drought and salinity in both Bangladesh and Pakistan and trying to cross those plants with cultivated carrots,” says University of Wisconsin PhD student Adam Bolton. “Breeding takes a lot of time, especially when you are working with wild material. We’d be thrilled if we could get new varieties out there in the next 10 years.”
No matter if your soil is salty or dry, or if you prefer red or orange carrots, eating half a carrot a day should be part of everybody’s daily diet. This project is helping ensure this will be possible, despite climate change.
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All agronomic and genetic data generated throughout this project will be shared in the future on the online database CarrotOmics.
Seeds of the improved wild-derived carrot lines developed during this project will be stored at the World Vegetable Center and the USDA-ARS to be shared under the terms and conditions of the Standard Material Transfer Agreement (SMTA) within the framework of the Multilateral System of the International Treaty for Plant Genetic Resources for Food and Agriculture.
The above is an update of an article that was published in the Crop Wild Relatives website on June 2017. You can read the original here.