From a new variety of Turkish parsnip to Madagascar coffee beans, the discoveries offer the prospect of better crops, medicinal uses and new garden displays

From new parsnips and herbs to begonias and roses, the world’s plant hunters discovered more than 1,700 new species last year, offering the prospect of better crops and new colours and scents in the garden.

The State of the World’s Plants report, led by scientists at the Royal Botanical Garden Kew in the UK and published on Thursday, reveals a cornucopia of new plants and assesses the risk to the plant world from pests and invasive species.

The most significant new food find was 11 new species of cassava found in Brazil which may help develop better varieties for the millions of people who depend upon it across the tropics. Capers, ginger, vanilla and sugar cane were among the other edible plants with newly found wild relatives.

Facebook Twitter Pinterest Sokinochloa australis, a new type of bamboo from Madagascar. Photograph: Royal Kew Gardens

The most striking new discovery was a bamboo from Madagascar which produces spiky, hedgehog-like flower clusters – but takes at least a decade to develop them and sometimes half a century. Many relatives of garden plants were also uncovered, including 29 new begonias from the forests of Malaysia, new roses and busy-lizzies from China and new violets and campions from Turkey.

The report found that more than 28,000 plant species are now recorded as having medicinal uses and new climbing vines from Borneo and Ecuador may add to the list, being relatives of plants already grown to produce treatments for Parkinson’s disease.

Finding so many new species in a year is not unusual and Prof Kathy Willis, director of science at Kew Gardens, said: “There are just huge areas we know nothing about. I find it really encouraging that there are many, many new plants to be found in the world.”

“Plants are critical to life on Earth and all aspects of human wellbeing,” she said. “I get most carried away with the new food crops, because I think one of the most worrying things about climate change is its impact on food security.”

Willis said wild relatives of crops will have survived for hundreds of thousands of years in all types of climate, meaning they will have useful traits, such as tolerating drought or disease, that may have been bred out of commercial varieties in return for higher yields.

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One recent example is a new species of coffee revealed in Madagascar. “It has got these really big coffee beans and quite happily survives in up to 40C,” she said. “The traits are perfect for saying this might be a good species for future coffee.”

However, finding these wild relatives, which are usually much less noticeable than commercial varieties, is not always easy. “They often look awful and are not in protected areas,” Willis said. The newly discovered parsnip in Turkey, she said, “is the most miserable plant you have ever seen.”

Some species have also almost vanished before discovery, due to loss of wild areas to human development. A unique flowering tree found during development of a uranium mine in Mali has fewer than 10 mature trees known, making it instantly critically endangered.

Facebook Twitter Pinterest One of 11 new species of cassava found in Brazil ( Manihot debilis). Photograph: Royal Kew Gardens

Researchers expect to continue to unearth new species in future and Kew scientists are going to work with the Colombian government to explore new areas, now accessible after a peace deal with rebels in December. “It is one of the most biodiverse areas in the world and people have no idea what plants are there,” said Willis. “The government is very keen to understand what plants they have before large industry is going in and stripping the plants out.”

The discoveries are providing new knowledge to help conserve plants but Kew’s report from 2016 found 20% of all plants are endangered. The new report reveals that pests, diseases and invasive species continue to harm plants and could cost world agriculture over $500bn (£386bn) a year if not stopped.

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The top pests, including the cotton bollworm, tobacco whitefly, two-spotted spider mite and the taro caterpillar, are often already resistant to dozens of pesticides and present in scores of countries.

One threat highlighted by the report is the emerald ash borer, a beetle native to east Asia but which is carried to the US in wood packing material and is now expected to kill most of the 8bn ash trees in the US. Richard Buggs, a plant health expert at Kew Gardens said the beetle is now in Russia, near Moscow. “There is a real chance it could come to the UK and it is far more damaging than ash dieback,” he said, referring to the fungal disease that has rapidly spread across the UK in recent years.

Willis said there were often knock-on effects from losing plant species, such as ash trees, which can cut air pollution: “It’s not just that you lose your street trees, you get an increase in respiratory problems and an increase in mental health problems.”

Facebook Twitter Pinterest A new species of Orchid from Cambodia, Porpax verrucosa. Photograph: Andre Schuiteman/Royal Kew Gardens

She said plants were often underappreciated: “Currently there is a disconnect between plants and people. The fact that so many of these are plants that we rely on day in day out or have the potential to provide us with a new source of drugs or food or fuel – I can’t think of a stronger argument for conserving plants than that.”

The report also examines wildfires, which burn 340m hectares of vegetation a year, an area the size of India. Some fires are natural and, overall, the area burned is not rising but some regions are seeing a higher frequency and intensity of burning due to the growth of more easily ignited plants.

In Chile, non-native eucalyptus trees have been widely planted, often as part of carbon offsetting schemes, but they increase the fire risk, as does the spread of invasive European gorse in New Zealand.