The US already has some 20 citrus patterns tolerant to greening
Mª Angeles Forner, the person responsible for citrus patterns at the Valencian Institute of Agricultural Research (IVIA), stated at the Picassent’s XXXI Citrus Congress that the United States already had nearly twenty citrus patterns that were potentially tolerant or resistant to the greening or HLB disease that is sweeping the plantations of Florida and other North American states, as well as those in Brazil and several countries of that have a relevant orange production.
Four of the twenty North American patterns of interest are in California and the remaining 16 in Florida. Mª Angeles Forner said that, even though researchers from both states were working with them, they were still in the first stages of this research, so it was still too early to know the scope and virtues of each pattern.
Given the obvious interest of these findings, a farmer attending the congress asked Forner if they had brought any samples of these patterns to the IVIA so they could study their characteristics there and where they could get the appropriate plant material in case the greening affected the plantations in Valencia and in the rest of Spain. The researcher acknowledged that the IVIA still had not taken any decision in this regard, and that they hadn’t imported any of the referred patterns so far, which surprised the audience who believes they should have already undertaken some initiative of this type.
At the moment, the bacteria causing the greening disease hasn’t been detected in Spain, but it has been a long time since insects vectors that can propagate it, whose populations are spreading throughout the territory, were detected in Portugal, the Canary Islands, and Galicia. This means that if the pathogen arrives, in any clandestine import of infected plant material (which don’t have many controls), the propagation could be easier, as the vectors are already close to the country, which could lead to a truly disastrous situation.
Faced with this negative possibility, the technical services of the agrarian administrations have been carrying out controls to determine the hypothetical presence of vectors (which fortunately have not been found in the Valencian Community) and of the disease itself, of which there is no presence in Spain or Portugal. However, the disease could arrive to the country, something that is dreaded by technicians and politicians, who constantly recommend the care that must be taken to prevent a catastrophe like the one suffered in Florida or Sao Paulo, which lost hundreds of thousands of hectares to this pest.
The country’s prevention work is suitable, but it is clear that Spain must also try to quickly dispose of plant material that, if the disease spreads, could be a viable alternative for it; something that is being done in the United States, but not here. Perhaps Spain hasn’t taken this measures because the disease hasn’t been detected in the country yet, so they haven’t experienced its disastrous effects.
However, it would not hurt to start acting in this direction just in case. Spain should intensify its research to try to find resistant or tolerant hybrid patterns, get samples of all the work obtained in this direction from around the world and, at the same time, work to develop biotechnological applications that can contribute in this direction. There are more and more specialized opinions that point to the convenience of deepening the applications of the CRISPR biotechnology tool, which was created by Valencian researcher Francisco Mojica, from the University of Alicante.
It worth noting that when Spain was affected by the expansion of the tristeza virus, which killed more than a hundred million orange trees and mandarins, the country at least had the effective alternative of patterns that were tolerant to that disease, on which its current citriculture is based. If these patterns had not existed, there would hardly be any orange production left in the Valencian Community. The new potential threats, the greening and Xylella (which can also affect citrus), could have a similar negative effect on the crops, with the aggravating circumstance that the country still doesn’t have any alternatives to face it. The country has to look for them.
Publication date: 10/31/2017