Creating a broccoli for all seasons to hedge against climate change
The last time food was rationed in England, Winston Churchill was still prime minister of the country. Earlier this month, however, Britons experienced a blast from the past as bad weather in Spain caused a severe vegetable shortage in the UK, leading some supermarkets to ration the number of greens that customers could buy. But could creating a new line of broccoli for all seasons help avert another veggie crisis, the next time the rain in Spain becomes a pain?
Though it might not look like it, the part of the broccoli plant we eat is actually a flower structure. In order for the plant to reach this flowering stage, the temperature has to be just right, and key to this part of its growth cycle is a process known as vernalization. Put simply, some plants need to undergo a period of cold weather before they can flower, and broccoli is one of them. If it doesn't get cold enough, it flowers late, or worse, not at all, making it a high-risk crop for farmers.
It therefore goes without saying that erratic weather patterns are bad news for broccoli growers who can't predict how much cold weather they are going to get each year. And because farmers have no idea when the plants will flower, this in turn creates a problem for crop scheduling.
To address this problem, crop geneticist and lead researcher Judith Irwin developed a new line of broccoli that is not only fast-growing – it goes from seed to harvest in just around two months – but is also resistant to the climatic whims of the season, since it can be grown all year round in protected conditions.
Based on past research conducted by John Innes plant biologist Caroline Dean, the road leading to this development involved crossing different lines together to find the gene responsible for flowering time (or "heading date" as it is known in the horticultural industry). In the course of their studies, Dean and her team found that small changes in a gene known as FCL result in a range of heading dates found in different broccoli varieties.
"We harnessed our knowledge of how plants regulate the flowering process to remove the requirement for a period of cold temperature and bring this new broccoli line to harvest faster," explains Irwin. "This means growers could turn around two field-based crops in one season, or if the broccoli is grown in protected conditions, four to five crops in a year."
Given that the UK grows only 23 percent of its own food, this new development could help address the problem of seasonality and the country's dependence on imported crops by allowing broccoli to be grown year round in contained horticultural production systems such as greenhouses or vertical farms.
"This is a very exciting development as it has the potential to remove our exposure to seasonal weather fluctuations from crop production," she adds. "This could mean broccoli – and in future other vegetables where the flower is eaten, for example, cauliflowers – can be grown anywhere at any time enabling continuous production and supply of fresh local produce."
That said, speed of growth is one thing, flavor is another. When asked about the taste profile of this new line of broccoli, Irwin would only tell us that nutritional and flavor tests will form the next phase of research. Nevertheless, the researchers at the John Innes Centre are aiming to provide pre-breeding material (i.e. plant lines with specific traits) to plant breeders and growers for year-round scheduling of Brassica vegetables.
Further testing is being conducted under true protected and field commercial growing conditions to prepare this new line for commercialization.
Source: John Innes Centre