Climate Crisis Threatens UK’s Fruit Trees Due to Commonality of Plant Disease That Thrive in Warm Weather

Fruit trees in the United Kingdom are under threat as a result of the climate crisis, as plant diseases that thrive in warm weather become more common.

Every year, the Royal Horticultural Society (RHS) compiles a list of the most common plant diseases reported by its nearly 500,000 members.

Gardeners send photos or samples of diseased trees, crops, or flowers to plant pathologists, who can identify the disease.

Warmer UK weather adds to spread of fruit tree diseases

(Photo : CHRISTOPHE SIMON/AFP via Getty Images)

According to Dr. Liz Beal, a plant pathologist at the RHS, this is a direct result of last summer's extreme heat, which caused many plants to become stressed and thus more susceptible to problems when rain, combined with continuing mild temperatures in the autumn, provided the ideal breeding ground for diseases to spread.

Most fungi require warm, wet weather to spread and infect plants.

While many of these diseases cause fruit to rot or have an unappealing appearance, others can be fatal.

A rise in Silverleaf, which can destroy blossoming cherry trees, is especially concerning, as per The Guardian.

"With warm weather expected again this year, gardeners can act now to reduce risks by pruning apples and pears that are still dormant and avoiding pruning Prunus - flowering cherry - until the summer," Beal explained.

Prunus is susceptible to silver leaf and the fungus is less active in the summer.

Horticulturists are on the lookout for new diseases and invasive species, as warmer weather combined with international plant trade increases the likelihood of new outbreaks in the UK.

Dr. Beal is concerned that blueberry rust will become more common as people grow the "superfood" at home.

"With gardeners eager to experiment with ever more exotic fruits and vegetables, it is likely that we will see more blueberry growers succumb to a new rust already prevalent in many parts of the world," she said.

People should buy blueberry plants from reputable suppliers and keep an eye out for rust-yellow-orange pustules on the underside of the leaves.

In addition to the effects of climate change, establishing orchards has become a popular gardening hobby because they benefit biodiversity and produce delicious fruit.

Another factor contributing to the spread of these diseases is the growing popularity of fruit tree planting, particularly of heritage varieties that may be less resistant to diseases such as apple and pear scab, apple canker, and apple powdery mildew.

This is not to say that people should not grow them, but they should take additional plant health precautions such as ensuring the tree is planted in the right place, such as well-drained soil, pruning correctly in the winter months to remove issues early, and clearing fell fruit that shows evidence of rot to reduce the chances of spores harboring at the tree's foot.

Also Read: Loss Of Large Fruit-Eating Animals Could Accelerate Climate Change

Implications of Changing Climate on Productivity of Temperate Fruit Crops

With global temperatures expected to rise by up to 6°C by the end of the twenty-first century compared to pre-industrial levels, this agroclimatic metric is unlikely to remain stable, as per Longdom.

Higher evapotranspiration indices may reduce or deplete soil water reservoirs, causing water stress in plants during dry seasons.

As a result, water stress not only reduces crop productivity but also hastens fruit ripening.

Global warming caused vigor loss, fruit-bearing ability, fruit size reduction, less juice content, low color, reduced shelf-life, and increased pest attack, resulting in low production and poor quality apple crops.

Climate change will also cause the vulnerability, rarity, and rapid extinction of many temperate fruit species.

Temperate fruits are primarily produced in the 30° to 50° N and S latitudes.

Their cultivation may extend to lower latitudes (15°-30° N and S) at higher altitudes, as well as higher latitudes with large bodies of water and a favorable climate.

Cool winter temperatures are critical for meeting their chilling requirements, ensuring homogeneous flowering and fruit sets, and generating economically sufficient yields.

To protect sensitive tissues from winter damage, trees in temperate or cold climates have evolved the mechanism of dormancy.

Endo-dormancy is broken after a certain period of cold conditions (chilling), and the tree is ready to resume growth the following spring.

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