Pomologists know how to grow the perfect fruit. But as the world gets hotter, can they save it from extinction?
Richard Volz was 42 when he took control of the future of one of New Zealand’s most valuable products. The country is known around the world for its crisp, juicy apples, from the native Braeburn to the bestselling Gala, and catchy newcomers such as Envy, Jazz and Smitten.
It was 2001, and as the new head of apple and pear variety breeding at New Zealand’s top agricultural research group, Volz’s job wasn’t only to create new varieties that might one day join the pantheon of those illustrious names. He was also tasked with a particular challenge from a group of apple farmers on the other side of the world.
Volz’s home in Hawke’s Bay, New Zealand, enjoyed almost perfect weather for growing apples: cool winters followed by sunny summers that were not too intense. By contrast, Catalonia, Spain’s top apple-growing region, is much hotter, with far less rain. Catalan growers had come to New Zealand in search of new varieties that would be capable of flourishing in their climate.
New Zealand had an exceptional set of seeds and seedlings. But no one could say for sure whether, buried within this prized germplasm, were the genes to produce an apple that would grow in conditions beyond the known limits of pomology. There was another difficulty. Breeding, testing and launching a new apple takes a long time, often more than 20 years. Volz was gambling that he could find what Catalonia needed before he retired.
One afternoon this summer, I stood with him in an orchard in Lleida, a province in the autonomous Spanish region. The temperature had just passed 40C. Volz, now 64, is a wry but determined man with a thinning crop of curly hair and a trim grey beard. He was perspiring gently in a loosely buttoned blue shirt, shorts and sandals. He held a large, sharp knife and was about to show me the outcome of his two decades of work.
Too much heat is tough on apples in many ways. Each one needs up to 70 litres of water to ripen fully. The trees require winter chill to give them a rest before budding in the spring. They like warm summers with cool nights. It is that diurnal drop in temperature that turns apple skin red. If it does not happen fast enough and growers leave fruit to ripen longer, the flesh can go soft.
Volz picked an apple and cut it into four slices, biting one and handing me another. “Mmm. Not quite the texture that I was bragging to you about yet. It is sweet, quite crisp and juicy, but immature,” he said. It was still several weeks until harvest. The apple’s starches had yet to fully turn into sugar, and anthocyanin pigments had yet to make its skin deep purple-red. But here at last was the Tutti, also known by its plant variety name, HOT84A1.
It is the first fruit of the Hot Climate Partnership, a collaboration between scientists and growers in Spain and New Zealand, including Volz’s employer Plant & Food Research, and will be followed by others. Tutti will be sold for the first time in Spanish supermarkets later this year. Volz’s gamble has come good: he and his collaborators have produced the first apple designed to be grown in very hot weather.
But something else happened in the intervening decades: the pace of climate change outstripped expectations. Last summer was the hottest in Spain in 700 years, while Hawke’s Bay was struck by a devastating cyclone in February. That left another question hanging in the air in the Catalan orchard: does the arrival of Tutti mark the start of a new era for the apple industry, or the beginning of the end?
‘Why are you growing apples from NZ?’
Four days after returning from Spain, I walked to my local market in east London and found an unusual apple. It was a Discovery, freshly harvested, rather spotty and only partially red, but still sweetly fragrant when I bit into it. Discovery was bred in England in 1949 by crossing two Victorian varieties, Worcester Pearmain and Beauty of Bath. When I went back to the market a couple of weeks later, Discovery had already vanished, replaced by the tart and aromatic Cox’s Orange Pippin, raised from a seedling in 1825 by Richard Cox, a retired brewer.
Cox is one of at least 7500 varieties going back centuries that might once have been in the apple hit parade, but are mostly now forgotten or sold as “heirloom” specimens in farmers’ markets. Compared with new cultivars (varieties produced by selective breeding), many are fragile, easily bruised or prone to going soft. “People say, ‘Why are you growing apples from New Zealand? Local ones are much better,’ half-remembering when they were young,” says Joan Bonany, the Catalan apple breeder who has worked with Volz since 2002. “Bullshit. No way.”
The fact is, most apples are bought in supermarkets. That makes Harry Wilder among the most influential people in the European apple industry. As senior agronomist at Marks and Spencer, he has first pick of new varieties that will entice middle-class shoppers to pay premium prices. M&S is an exacting buyer, specifying not only colour, texture and taste, but sometimes the precise week during harvest in which they are to be picked.
“When Cox are at their best, they are very good apples, but that is only for a short window,” Wilder says. Cox “heritage apples” is one of the 17 varieties M&S sells, but their fleeting availability counts against them. Shoppers want not just a nice apple, but one that is consistently available. “People’s understanding of seasonality has slipped away.”
About four in every 10 apples sold in M&S are Pink Lady. The first apple to be turned into a brand, it was originally bred as the Cripps Pink in Australia in 1973, when apples were becoming a commodity. Back then, supermarkets squeezed growers for the lowest prices, regardless of variety. By the time Pink Lady was trademarked and began reaching Europe in the 1990s, growers saw an opportunity to rebel against the grip of the supermarkets. They insisted on selling it at a premium price in pink packaging and marketing it as a brand, not just another variety. Supermarkets were not happy, but growers prevailed.
The “club variety” apple, with strict quality controls and a snappy brand name, was born. New Zealand followed suit. Germany bred a variety known in the US as Piñata (“the apple with heirloom roots and a tropical twist”) and France released Tentation (“it contains all the pleasures”). The US caught on with SweeTango and Cosmic Crisp.
As these brands proliferated, they converged around a common standard. Today’s supermarket apple is a perfect globe, with no blemishes or russeting around the stem. When you bite into it, the skin gives way crisply with a ringing sound. It is firm, but not heavy or gritty, and the cells in its flesh rupture instantly, releasing abundant juice.
Consumer preference for red apples is partly due to a belief that redness indicates ripeness. There is some truth here — many apples turn red late in the ripening process — but it’s not an entirely reliable guide. Granny Smiths remain green, of course, and other cultivars are yellow even when ripe. “Shoppers make their choice of apples quickly, and getting them to think more thoroughly is quite hard,” says Sara Jaeger of Vescor Research in Denmark.
In modern packing plants, such as one owned by the Cafa Merano co-operative of 300 fruit growers in South Tyrol, Italy’s prime apple-growing province, each apple passes through a scanner that photographs it from 92 angles for colour and blemishes, while another camera looks into the stem cavity for undesirable cracking. A single variety such as Golden Delicious can be sorted into 70 categories — including the most desirable red-blushed Goldens — before being dispatched across Europe. The grower gets paid according to how many apples fall into each category.
People’s understanding of seasonality has slipped away.
In Catalonia, Bonany produced an octagonal cutter and sliced a ruby red apple into pieces. It was one of the varieties, still under wraps, that will follow Tutti. I took a bite, and he asked me to rate it on scales of crispness (amount and pitch of sound first generated when first bitten) and juiciness (amount released in the first three chews with back teeth).
The pressure to find the perfect apple is unrelenting: if anything, shoppers in fast-growing Asian markets are even choosier. The Japanese like large apples to share in slices at the end of meals. “There is a higher weight [put] on appearance in Asia,” says Volz. He recalls talking to one exporter to Asia: “He told me, ‘This is what I want you to breed: big, red, sweet. Don’t worry about anything else.’”
Over the past 50 years, the US$99 billion (NZ$167b) fresh-apple business has turned itself into a highly optimised machine to provide exactly that. Now, climate change is pushing the machine to run faster.
Numbers game
Apple breeding is a peculiar profession, demanding deep expertise and extraordinary patience. The time it takes to cross, develop and launch a new variety of apple means that a breeder will be lucky to have one big hit in their career. In compensation, apple breeders get to play God.
Luther Burbank, the 19th-century breeder of exotic hybrid plants in California, called his catalogue New Creations and became feted as the “high priest of horticulture”. No breeder today is as well known, but all share Burbank’s special power: “You are creating something and making a choice. This one is in, this one is out,” says Volz.
More accurately, one is in and thousands are out. The difficulty with apples is that, like humans, they are heterozygous: any two offspring of the same parents are very different. Even the seeds of one apple will produce different varieties, probably none of which would taste very good. Left to their own devices, apples are brilliant at biological diversity and terrible at reliably producing what people want to consume. That makes finding the right apple a game of very large numbers.
It could drive you mad if you thought about it too much. No breeder can taste every apple from every tree, and they might easily walk past the one that millions would want to eat — the original Honeycrisp tree was discarded. When I asked why he had picked a particular fruit to taste, Volz replied: “Breeder’s intuition.” He smiled, but it is true. Apple breeders need a sixth sense.
To breed Tutti and the rest, Volz chose promising varieties to cross and acted like a bee, dusting dried pollen from one on to flowers of another to produce new apples. He leaned heavily on Envy for its crispness and texture, along with other varieties with red skins. In total, he took 253,510 seeds from apples grown between 2002 and last year. These were sent to Irta, the Catalan government research institute where Bonany works.
Bonany started growing those seeds in the test orchard in Lleida. He and colleagues have raised 90,000 trees over the past two decades. They produced thousands of apples and Bonany and Volz tasted many of them, seeking out the few that could become stars. “Elite apples are like diamonds. They are very rare,” Volz says. From the original 90,000, only 357 varieties made it to a second round of trials, 18 went to a third and 13 reached the final round.
Once they have found an outstanding apple, breeders clone it, eliminating the risk of duds. Instead of letting its pips grow, buds from seedlings are grafted on to rootstock and grown into trees that produce only that variety. Every Tutti apple comes from a clone of a single tree that was selected in Lleida in 2007.
The second propagation of Tutti trees took another five years to bear fruit; the cultivar then had to go through two more trial phases. Trees were planted in various locations in Catalonia and across Europe to ensure fruit was consistent and trees adaptable. Trees were finally made available for growers to buy in 2019, 17 years after the first pip was planted.
Climate crossroads
In the orchard in Catalonia, four apple trees were dying of thirst. They were a pitiful sight in the burning August heat, their leaves brown and shrivelled, their branches bearing a few tiny, green fruit. Along the row, others had been irrigated and were flourishing, but these four were in obvious distress.
As I examined them with Volz and Bonany, it somehow felt cruel, especially as the man depriving the trees was standing next to us. Joan Girona, a senior researcher and irrigation specialist at Irta, had stopped watering them in May. They were planted in a lysimeter, a large scientific container with its own water supply, to measure exactly how much hydration apple trees in Lleida need.
“I sometimes came here to observe them and thought, imagine if all the apple trees were like this,” said Girona. He planned to switch the irrigation back on, but did not know if they would survive. The trunks of apple trees should be at -1.5 megapascals (MPa), a pressure scale that measures hydration. A -5MPa reading means fatal stress. These four trees were at -6MPa.
We have a very big problem with Gala here.
Since May, there had been only two rainstorms to refresh the trees naturally. The lysimeter also enabled Girona to weigh them and the earth around them, and to calculate how much moisture was evaporating from their leaves and the soil daily. The answer was 35 litres. Other trees, including the Tutti ones, would need to receive that amount of water in high summer to compensate.
Girona has worked on water use in agriculture for 40 years. For most of that time he has had trouble gaining the attention of farmers. That changed this year. In April, after the spring rains failed to materialise, he warned them that they might have to sacrifice their entire crop by removing the fruit to keep their trees alive. “The situation was really drastic, you could see it in their faces,” he recalls. As it turned out, the apples survived. Growers received about half their usual irrigation, and summer rain carried them through. But these four trees were a memento mori.
One problem is that most growers in Lleida still employ the traditional method of irrigating trees by flooding the fields every two weeks. This is an extremely wasteful practice, by which each apple gets about 54 litres of irrigated water. Drip-watering along pipes is far more efficient, potentially reducing that figure to 19 litres per apple.
But it can cost €40,000 (NZ$71,000) per hectare to buy new trees, pay patent and brand royalties, install metered irrigation and protect the fruit from sunburn and hail with netting. Until now, there has been little financial incentive to make such a heavy investment in Lleida because growers are not charged by the litre for their water. This year’s drought might be the necessary shock. Instead of less water, it showed that there could be none.
The next day, we glimpsed the future in Girona, a province in eastern Catalonia that includes the tourist beaches of Costa Brava. More growers there have invested in drip irrigation, partly because they face competition. They have to prove that their apples are as deserving as hotels and golf courses. “I need water and they need water. Maybe swimming pools are important for life,” said Albert Batlle, a local grower, with a fatalistic shrug.
Albert and his brother Martí oversee a farm that is part of Girona Fruits, a growers’ co-operative. In 2020, its members decided to plant Tutti, and the brothers now have 22,000 of the trees which will fully bear fruit next year. Their orchard is modern, with netting suspended from square concrete poles and a solar-powered drip-irrigation system. As we talked, the roots of the tightly spaced trees were being precisely hydrated.
Even this sophisticated operation is under inexorable pressure. Gala apples have stopped turning red fast enough before the three-week period in August when they are meant to be picked. “We have a very big problem with Gala here,” said Batlle. The Batlle brothers now want to grow more varieties that ripen later in the year, such as Tutti. They no longer need to worry about the autumn in Catalonia turning chilly and damp. “October is not like 20 years ago. It is milder now and it doesn’t rain,” Batlle said.
‘Tutti is remarkably inbred’
Despite centuries of experience, much of apple breeding was guesswork until quite recently. No one really knew what was going on inside the fruit’s genes to produce new varieties. That changed in 2010, with the first sequencing of the genome of a single Golden Delicious.
Detailed genomic mapping of apples has provided scientific confirmation of something that is intuitively obvious: many apples are closely related. Tutti’s grandparents are Braeburn, Gala, Splendour and Gala again. “Tutti is remarkably inbred. That’s not necessarily a bad thing. It’s how a lot of crop breeding is done,” says Nick Howard, a molecular apple breeder at the Dutch agriculture company Fresh Forward.
As the climate changes, and trees face more threats from pests and disease, questions are being raised about this lack of diversity. A study of 1000 varieties at a US government germplasm repository in Geneva, New York, concluded that “Americans are eating apples largely from a single family tree”. It found that a few cultivars had been used repeatedly for breeding in an effort to select for red skin and crispness.
Zoë Migicovsky, an assistant professor at Acadia University in Nova Scotia, Canada, led the study, which called for greater efforts to exploit the “tremendous natural genetic diversity” of apples. Wild apple trees adapted naturally to different environments over millions of years, after all. “We want consistent fruit quality but [to achieve it] we are using varieties that were bred 50 or 100 years ago, when climate conditions were very different,” she says.
Broadening the genetic base of apples with traditional breeding techniques would take even more time, though. If you cross a crab apple with a modern cultivar, you may gain disease resistance but the fruit is likely to taste terrible. “It’s quite a stretch to say, ‘We will breed with a cooking apple from the French Middle Ages and, in three generations, we will have one suitable for the market.’ In three [apple] generations, I’ll have retired,” says Fresh Forward’s Howard, who is 38.
Another possibility, as yet little-tried commercially, is gene editing, using technology such as Crispr. The sequencing of the apple genome has shown targets for desirable attributes. One is skin redness, which is controlled by a gene called MdMYB1. Instead of waiting for trees to mature to taste fruit, scientists could in theory silence or insert genes in seedlings to control the outcome.
If gene editing worked, it would be a lot quicker. Other fruits have already been edited. A Japanese company used Crispr in 2021 to enrich a tomato brand with healthy amino acids. Scientists at ETH university in Zurich have also experimented by engineering Gala trees to carry a copy of a fireblight resistance gene from a wild apple.
The hope is that “cisgenic” modification — using only genes from apples and not other plants — will be more acceptable to regulators and consumers than earlier technology. Gene editing is now legal in many countries but restricted in Europe, although the EU is moving towards loosening its rules. So far, genomics has mostly been used in apples to improve breeding by picking parents, or to screen seedlings for the best traits. Some breeders have also tried to speed up the 20-year testing cycle by putting apples through trials faster: one New Zealand variety was released after 13 years.
Even if apples can be developed faster, it could still become too difficult to grow them in Catalonia. After we tasted the Tutti crop in Lleida, we came into the shade to drink cold water. As we sat around a table, Bonany and Volz started to debate the future.
Tutti and other hot-climate varieties have shown the region can produce red, crisp, sweet apples at a temperature that few thought possible. But what if it keeps on getting hotter and loses its winter chill? “Are we at the edge of what is possible?’’ Bonany reflected. “There could come a point where it is not worth continuing.”
Across the table, Volz stirred. The New Zealander who had devoted so much of his career to extending the livelihoods of Catalan growers was not going to give up so easily. “I’m a little less worried,” he said with a grin and a glint in his eye. “You might think there’s no way that we could grow apples at 50C. But I put it out there that it’s in the germplasm. We’ve just got to find it.”
Written by: John Gapper
© Financial Times
