The 20-year process of developing a new cherry variety
Chile is the largest cherry exporter in the world with a record-setting 2022-23 season totaling 415,315 tons.
China is Chile’s primary market accounting for around 80% of the total volume.
Despite how consolidated the Chilean cherry market is, the country has yet to develop any varieties of its own.
This is what breeders from the Catholic University of Chile, along with local growers and exporters, have been working on since 2010, developing local sweet cherry varieties in Chile with a breeding program called Fruit Consortium.
“Our main goal is the development of a new early and late sweet cherry variety adapted to the climatic, commercial, and logistical requirements of Chile, with the objective of coping with climate change and maintaining competitiveness,” said Marlene Ayala who is in charge of the breeding program at the Catholic University, during a presentation at this year’s Macfrut.
For Chilean export fruit, one of the most important aspects to consider is post-harvest due to its geographical position which makes transport to Asia last, on average, more than 15 days.
“During these years we have established a diverse germplasm collection with massive and diverse populations of hybrids in two locations, we have been doing phenotyping and selection, identifying first and second hybrid selections as well as advanced selections,” said Ayala.
Ayala indicated that by 2030, they expect to have their own varieties. The focus for the development of these is on production, quality, and state of the fruit at storage.
“We need high productivity, with very tolerant varieties, some have to be low-chill and able to tolerate environmental stress,” she added.
Due to market demands, the size, firmness, sugar content, and weight have to be of great quality, another priority for Chilean breeders.
One of the challenges is finding alternatives for early varieties for October and early November, as well as late varieties to harvest at the end of January and February.
Overview of the program
“After 13 years with the program, we have identified four candidates for advanced selection. We are going to graft these into rootstocks and establish 13 in multi-sites that belong to stakeholders of Fruit Consorcio. From there we will start commercial evaluations so we are expecting to have a new variety in the year 2030,” said Ayala.
The program has tried more than 625 genetic cherry combinations throughout the entire process. The seedlings were established at the Pirque research and experimental station, near the capital city of Santiago.
When the hybrids are in the field, experts observe the harvest state, and fruit quality and look for cracks in the fruit. When the selected hybrids are in the lab, they measure fruit quality again as well as firmness, size, and sugar level.
Second-selection hybrids are then exposed to particular storage and lighting conditions in order to measure post-harvest life.
“Currently, we have around 81-second selection hybrids, picked from around 1,000 individuals that were evaluated in the lab,” said Ayala.
Of the 81, 36 have already been grafted and established in the field and 38 grafted in pots, and the other seven will be grafted this year.
The program offers field days at their sites to exporters, growers, and representatives from the government. They have even received a visit from the Chinese ambassador in Chile.
Regarding field days, Ayala noted that they organize “late and mid-season field days in which we analyze the fruit and the trees and receive great feedback from our guests which is very important for us.”
Most advanced candidates
From the 36 second selection varieties established in the field, 24 are already phenotype and from these, they have selected the four candidates for advanced selection.
These four candidates will be grafted in two different rootstocks and established in orchards in three different locations.
Of the four candidates, there are two early-season varieties (Oct-Nov), and two mid-season varieties.
“All of these varieties have been very well evaluated during field days and have very good storage performance,” indicated Ayala.
Ayala said that they will continue working hard with advanced selections as well as all other hybrids in the project to develop a generational package, in order to achieve the goal of the first Chilean variety by 2030.