Two hours from Santiago by road, in the heart of the O'Higgins fruit and vegetable region, a group of Chilean scientists strives to create by 2019 a generation of "super-trees" resistant to the damaging effects of climate change.
The “super trees” would be prepared to face events such as drought, the decrease in the rainfall regime and the concentration in short periods of time of winds, frosts and storms, all this as a consequence of global warming.
The ravages of climate change on fruit productivity are fundamentally associated with manifestations of so-called “abiotic stress” (environmental), such as floods, frosts and “acid soils”.
In addition, experts predict that by 2050, there will be a drastic decrease in water resources, with the consequent damage to agriculture.
With the mind set on reversing this situation, researchers from the Center for Advanced Studies in Fruit Growing (CEAF) in Chile have been working since 2009 on the development of fruit tree species that are resistant to inclement weather.
"We are focused on working on the roots, the program is focused on obtaining new plant materials for the rootstocks," explains Felipe Gaínza, director of the CEAF's Genetic Improvement line.
Grafting is a method of artificial vegetative propagation of plants in which a portion of tissue, from a plant, joins over another already established, in such a way that the set of both grows as a single organism.
The part of the plant into which the variety is grafted, called the rootstock, contains the root system and a portion of the stem.
Chilean scientists are working on the development of new rootstocks "that are an alternative to those that are commonly used, which are genetically obsolete," explains Dr. Gaínza.
Only in the Chilean region of O'Higgins, where the Center for Advanced Studies in Fruticulture operates, there are 25,684 hectares dedicated to the cultivation of peaches (peaches), nectarines and cherries, which represents half of the surface dedicated to these crops in Chile .
Stone fruit trees
These fruit trees with stone inside are the species that Chilean scientists are working with to make them more resistant or tolerant to adverse weather conditions.
For this, the researchers carry out analyzes at the molecular level, to see how some genes are expressed in the face of these problems, the interim director of the CEAF, Mauricio Ortiz, tells Efe.
These studies are carried out at a physiological level, to determine "what changes are generated within the plant"; at the anatomical level, "to see the adaptations that the plant generates in the face of changes, and at the field level," to observe how it behaves in its natural environment.
In 2011, scientists began crossing nine selections of stone rootstocks, in order to make them more tolerant of extreme conditions.
"For example, in the hybrid between a peach and an almond tree, the latter provides resistance to drought and tolerance to nematodes, a soil pathogen that affects the roots," explains Dr. Ortiz.
Another of the species with which the peach tree is crossed is the plum, which provides greater resistance to flooding and creates a fruit that tolerates the adverse environmental conditions derived from climate change.
More resistant plants
Researchers use biotechnology techniques to clone the genes of the most resistant and tolerant plants through their DNA and thus develop molecular tools that help to select early the rootstocks developed by CEAF.
When fruit growing in Chile began, recalls the president of the Association of Producers and Exporters of the O'Higgins region, Francisco Duboy, “the plants were brought from California, because that state has a climate similar to that of the central area of Chile".
"But postharvest was not considered," adds Duboy, and that is why we are now working on the creation of clone trees that adapt to sudden climatic changes and that also resist long transfers during export. "