Citrus greening, or Huanglongbing (HLB), is the biggest threat for the citrus sector. In fact, the Mediterranean is the only large productive area which, for the time being, has not yet been affected by the appearance of this bacterium. The situation turned upside down in 2014, when the presence of one of the two vectors known to be capable of transmitting the disease, the Trioza erytreae, was detected in Galicia. In 2015, the Portuguese authorities discovered another breeding place of this insect near Oporto. Today, 4 years later, this psyllid from Africa has traveled almost the entire Atlantic coast between La Coruña and the Lisbon area and is just 190 km away from the first Spanish citrus plantations (Huelva) and only 170 km away from Portugal's main citrus producing province: the Algarve.
Aware of the seriousness of the situation, the Citrus Management Committee (CGC), the national association that brings Spain's citrus exporters together, has estimated the possible economic impact for the Spanish citrus industry of the entry of this pathogen. Their conclusions, given that there is no cure, and taking into account the experience of Florida, are almost apocalyptic. 7.5 years after its entry, the production of oranges, mandarins and lemons would be halved (from 7 million tons to 3.6 million), and after 15 years, citrus fruits would become a residual crop.
The report is based on the production data from 28 seasons in Florida, and has an outstanding level of detail compared to those of the world's biggest citrus growers affected by the disease (such as Mexico, Brazil, South Africa, India or China). In this North American state, the presence of the HLB was confirmed in 2005, but the disease must have settled down years earlier. In the 1997/98 campaign, Florida reached its record production, with 12.3 million tons. At present, only 25% of that remains; that is, a little more than 3 million tons. In view of this progression, it is estimated that Florida's production could disappear by the 2024/25 season (as long as no cure is found for the disease).
The study acknowledges that there are elements in favor and against the extrapolation of Florida's data to Spain. The different climate, the hurricane winds that favor the displacement of the vector insect at great distances, the very fact that the psyllid present in Florida (Diaphorina citri) is different from that located in the peninsula (Trioza erytreae) and that the latter is a carrier of A form HLB (the African one), which is less aggressive than the Asian one present in America. All of this would lead us to expect a slower development in our country. At the same time, the study highlights how the smallholding of many farms, especially in Valencia, as well as the proximity between plantations, the progressive abandonment of fields that are not monitored or cared for and the lack of investment in R&D to tackle the disease would act as decisive factors to accelerate its spread. All in all, the impact on a citrus industry such as the Spanish one, focused on fresh marketing, would become clear soon after the bacteria started to spread, as the fruits from infected trees cannot be marketed due to their greater acidity and its bitter taste. Long before the trees die, the fruit won't have a market.
Given the proximity of the Trioza erytreae (which in addition to carrying the HLB, is in itself a pest able to cause serious damage to the citrus areas of the Algarve and Huelva), the CGC has asked for the procedure to release a parasitoid brought from South Africa (Tamarixia dryi) to be sped up. This insect is known to be effective in the control of the population of the HLB vector, and its presence would be key to slowing down its spread. In addition to this, the sector has also requested the allocation of more EU and national funds for research in centers such as the IVIA (in the Region of Valencia) or the IFAPA (in Andalusia).
Given the seriousness of the threat, the CGC (and the sector as a whole) has stayed in touch with the Spanish Government and the EU authorities, insisting on the need to intensify the control measures on the imports from affected areas susceptible to carrying the vector. Even more important than that would be to take extreme precautions at border inspection posts, at ports and airports, to avoid the illegal entry of buds (for grafting) or plants that could be contaminated by bacteria.
According to the study, the practical disappearance of the Spanish citrus industry would entail:
* The loss of 200,000 direct jobs (57,000 in handling, preparation, packaging and marketing and another 143,000 in the harvest).
* The disappearance of another 79,000 jobs linked to the production itself.
* The loss of a turnover amounting to an average of 4,000 / 4,310 million Euro per season, with 3,100-3,224 million generated from exports.
* A great impact on the logistics sector: 174,000 trucks carrying citrus fruits cross the Spanish border each campaign. To this we must add the distribution of the 1.4 million tons that are marketed in Spain and the transportation of 6.8-7.3 million tons from the field to the warehouses.
* Losses and unemployment in related activities (packaging, pesticides, fertilizers,...)
* A great environmental impact due to the abandonment and degradation of 300,000 hectares of trees, responsible for the absorption of hundreds of thousands of tons of CO2.