Planting avocados in Spain was thought to be impossible - until 1966, when the German Dieter Wienberg insisted on making it a reality. This marked the origin of La Mayora, an experimental farm of the CSIC that pioneered the 'green gold' revolution. Half a century later, this is bearing fruit. In the midst of a global craze for avocados, half of all avocados produced in Europe are planted in Malaga and Granada.
In fact, succeeding in the production of a tropical crop in the southeast of Spain was an agronomic feat that is currently yielding a great profit to producers of the Persea americana. In the last four years, the price of avocados has doubled as a result of its demand, and with it, the national production of this unctuous fruit.
According to the latest report of the WAO (World Avocado Organization), which has come to light in recent days, in 2018, Spanish consumers ate 19 million avocados more than in 2017, so consumption was 35% higher. However, the future of the Spanish avocado sector is still threatened, which shows the fragility of this nascent 'green gold' industry.
An ally against enemies
Two of the most feared words by Spanish avocado growers are "Rosellinia necatrix", the name of the pathogen that causes white root rot. This fungus is in the soil, it is very difficult to eliminate and it infects other trees with the underground contact of the roots. Recently, Andalusian researchers took a closer look at some avocado trees that, despite being surrounded by rotten specimens, were still healthy.
The key is not that their roots were immunized, but that they had been infected by another virus that competes with the Rosellinia, but which, fortunately for the avocado tree, does not cause any diseases. This new species, of fungal origin and named Hipovirus enteleuca 1 (EnHV1) had never been identified before and has become one of the best news for the avocado sector in recent years.
The EnHV1, whose discovery appeared in the magazine 'Frontiers in Microbiology', could become a biological control weapon to protect the trees in Malaga and Granada. In recent years, growers had intensified their battle against white rot, which has also recently spread for the first time to mango trees, and against the brown mite (Oligonychus punicae), which became a big pest in the Axarquía two years ago.
The Achilles heel
Hass avocados today account for 70% of Spain's total production, and that is a problem, or has the potential to become one. Those that are usually consumed in Spain are a hybrid between Guatemalan and Mexican avocados, and have reached that privileged place because they have many advantages over other varieties. For example, their skin changes from green to black, which allows consumers to know when they are ripe, and their harvest lasts for six months, from December to June, which is good for the producer.
However, La Mayora researchers warned that "the dependence on a single variety observed in different parts of the world can become a weakness in the long run for countries that, like ours, have a comparatively small production and with few options to expand." This concern is due to the climatic demands of this species, which allows other countries to produce them all year round.
"The commitment to meeting the European demand solely with avocados of the Hass variety could lead Spain to become a mere bridge for the re-export of Hass avocado from other regions of the world, something that is already done when there is no local production. This, without a doubt, could threaten the future of the crop's cultivation in our country," say the scientists led by Iñaki Hormaza.
According to the Water Footprint Network, producing a kilo of avocados requires about 2,000 liters of water (much more than what is needed for a kilo of vegetables, cereals, fruits or even milk) and that, in a climate like the Spanish, is not good news, when a large part of the annual European demand depends on our avocados.
A recent study by the Institute for Research and Training in Agriculture and Fisheries (IFAPA) in Andalusia focused precisely on long-term strategies to continue growing avocados in the region without ending up being forced to choose between watering or drinking, as has already happened in some South American regions that are especially dependent on this fruit. One of the main conclusions was that it is necessary to introduce measures to guarantee the sustainability of avocado crops in the south-east of Andalusia.
Improving the efficiency of irrigation systems, promoting deficit irrigation strategies or studying the preferences of European consumers are some of the recommended measures to prevent the death of the Spanish avocado industry due to an increasingly desertified environment. "Avocado agriculture will have to adapt to climate change and help mitigate its impact by promoting soil and water conservation policies," and the hardest of all, "by improving crop yields and using resources more efficiently."
Everything sounds very logical, but meanwhile, as reported by local groups such as the Cabinet of Nature Studies of the Axarquía (GENA), rainfed crops in the most subtropical region of the Peninsula are gradually being replaced by mangoes and avocados, which are much more lucrative.