Introduction:

Frequently forest plantations do not produce positive net incomes across the rotation, but are concentrated at the time of harvesting. This situation usually discourages landowners, who must wait until the end of the rotation to perceive the income of their investment, preventing plantation establishment.

Also it is frequent that in such situations the observed growth and the costs of the replanting activities contribute to condition or to avoid carrying out forestation operations.

One way to revert this situation is to provide landowners with a source of additional income, ideally of high value and annual return that should be associated and complemented with the forest plantations. Eatable mycorrhizae fulfill these requirements and additionally they can significantly contribute to improve the development of the plantation, diminishing replanting costs and generating a flow of income to a large extent of the rotation period, which can make the investment in plantation more attractive.

Chestnut (Castanea sativa) is an emergent species in Chile, included in the forest-diversification program promoted by the Government with interesting incentives to be used by small-scale forest landowners. Chestnut has high-quality wood, very attractive for the national and international market, where it is considered valuable timber. Main uses of chestnut timber are in the furniture industry, crafts and in the veneer industry. In addition, poles can be obtained from thinnings.

In Chile chestnut plantations of 5-35 years old were identified between Regions VIII and X that, in spite of being small and of experimental character, allow stating that the growth in volume of the stem is interesting, obtaining one cubic meter by tree around the age of 35 years.

This species pertaining to the Fagaceae family can be associated to soil organisms such as ectomycorrhizae, which act at the root level producing healthier seedlings since fungi mycelium consumes exudates by the roots reducing food availability for plant pathogens. Each tie point with the root releases to antibiotics, covering the root and protecting it from other fungi and bacteria. In addition, it releases growth hormones (IAA, ipa, went, Ana), increasing the root volume favoring rooting of plants and stakes. Finally, it allows roots to increase their surface of action, for nutrients and water uptake.

One of these symbiotic relations for the species Castanea sativa, corresponds to truffles (Tuber melanosporum), fungi of very high value in the national and international markets. This underground fungi grows in symbiosis with the roots of certain trees, like oaks, chestnuts and walnut, among others.

On the other hand, are the species Boletus edulis, Amanita caesarea, Boletus aereus, Cantharellus cibarius, etc., which appear in the international markets with very important values that make their incorporation in forest plantations in our country viable and promising.

Objetives:

To increase profitability of chestnut plantations established in the VIII Region through the use of superior genotypes inoculated with mycorrhizae of commercial value.

• To identify, select and develop propagation and inoculation techniques of mycorrhizae associated to chestnut of commercial value.
• To propagate chestnut selected genotypes through advanced plant propagation techniques.
• To evaluate the degree of colonization of mycorrhizae in chestnut experimental plantations established using inoculated plants.
• To transfer the knowledge about this productive alternative to potential users.
• To develop an investigation and plant micropropagation service unit.

Expected results

Results within the horizon of the project

• Identification of eatable mycorrhizae of high-commercial value, that may be associated with chestnut.
• Protocol of propagation of selected mycorrhizae species.
• Protocol of inoculation for the identified fungi.
• Micropropagated individuals obtained from 20 select clones of chestnut.
• Experimental units established in sites of the VIII Region.
• Survival, growth and inoculation success data for inoculated plants established in the field.
• Technological package on the new productive alternatives associated to chestnut.
• Laboratory of micropropagation and inoculation of plants for production of plants with sale aims.

Results behind the horizon of the project

• Commercial plantations with micropropagated and inoculated plants of chestnut.
• Chestnut wood production.
• Production of fruit bodies of eatable fungi.

Impacts:

• The direct economic benefit for a landowner will be to increase the profitability of its chestnut plantations through the generation of a permanent annual income in time, complementary to the income resulting from the wood sale of both species, by means of the sale of eatable fungi. Jointly it will be increased the quality and amount of wood harvested from plantations due to the use of individuals genetically improved with mycorrhyzae.
• For the Forestry Institute, this project offers the opportunity to improve its infrastructure of propagation of fungi and plants as the laboratory of biotechnology located at the Bío-Bío Seat will be improved. At the same time it will allow the Forestry Institute to obtain direct resources through the sale of services of propagation and inoculation of commercially attractive fungi for the production of chestnut plants.
• In the scope of the social benefit, with the implementation of this project it is hoped to increase the occupation to regional level as a result of the promotion to the establishment and handling of plantations with new forest species (chestnut), harvesting, commercialization and processing of eatable mycorrhyzae and fruits associated to these plantations.

Financing sources:

• INNOVA BIO BIO - FIA (Foundation for the Agrarian Innovation): $ 73.515.871 (US$ 122,526)
• INFOR (Forestry Research Institute): $29.345.265 (US$ 48,909)
• Associated: $23.890.000 (US$ 39,817)

Associated:

• Saúl Montecinos: Private Landowner
• Sergio Baeza: Private Landowner
• Nino Gómez: Private Landowner
• Chilean Forest Service (Conaf VIII Region)