Flavor, size, turgor, brix and bloom are some of the qualities demanded of blueberries in world markets, so renewing the varieties of obsolescent crops is a task that becomes urgent and from now on it can become an action. permanent, with increasingly shorter cycles. Even relatively young orchards will be forced to implement spares to meet these increasingly demanding standards.

In this task, in order to avoid the consequences associated with replanting the crop in the varietal replacement task, the grafting technique is being used. In this way, the structure and qualities of the original plant are used, and thus a better and faster result is achieved.

Replant or graft

The detractors of the implementation of the grafting technique maintain that the process is slow, because grafting a plant takes time and they do not consider it very viable in large modern plantations or orchards, with densities of more than 3000 plants per hectare. Another problem associated with the implementation of the grafting technique is the appearance of sprouts born from the adventitious buds, from the roots of the old plant, which can cause part of the original variety to emerge.

On the other hand, the detractors of replanting new varieties maintain that other problems have been observed in this field, such as irregular growths, low productive behaviors, browning and necrosis in the root and even the death of the plants in some cases. These behaviors are observed mainly linked to the presence of fungi, bacteria, actinomycetes and nematodes in the soil, also to the modification of the pH of the land and the occurrence of chemical alterations of nutritional origin, among other factors.

Matter of time

Undoubtedly, the time factor is essential to choose one or the other system, because the sooner you are in competitive conditions, the greater the presence in the market.

In the case of varietal replanting, experts advise that the most effective way to avoid the associated problems is to wait a prudent period between the uprooting of old plants and the establishment of new ones, in order that the dangerous pathogens present in the ground go dormant. Some experts place this waiting time at four years for the new material to behave optimally, so clearly the time factor makes this operation unviable from an economic point of view for the modern export industry.

Experience then shows that plant grafting is a much faster and lower-cost alternative, because the grafting technique allows the variety of crops to be changed without having to start up and replant.

At the Faculty of Agronomy of the University of Concepción, the agronomist and Master of Science in Sciences, Pablo Muñoz, has developed graft studies for years with the aim of replacing varieties and comments that in 2016 they carried out variety replacement trials since the VII to the IX Region of Chile, grafting Duke, Brigitta and Legacy, on O'Neal, Bluecrop, Chandler and Elliott, that is, on varieties that the market leaves out due to quality problems and condition of arrival in the markets.

The researcher assures that with the grafting modality in the plants the investment amounts are much lower and affordable for small and medium farmers.

Pilar Bañados warning 

The agronomist and berry specialist, Pilar Bañados, when asked about the graft, supports those who think that it is a very good option for varietal replacement and explains that, if they take care of good feet, in plantations that are in good condition instead of being forced to uproot them, grafting is a very good alternative.

“One aspect that is important to mention when talking about grafting is which varieties to replace with. When it is done with free varieties, such as Duke, for example, there is no problem. On the other hand, when one thinks about the possibility of grafting with protected varieties, affected by the payment of royalty, or even with Club varieties, this issue becomes more complex since it must first have the authorization of the respective licensee and if they are authorized, the payment of the corresponding royalties, and the delivery of fruit to the owners of the license, if applicable ”, warns the expert.