Soil porosity investigations in truffle orchards

Abstract

Those who are engaged in the production and research of the truffle as a special ecological trait  agree that beside of the climatic attributes , the soil circumstances play  important role  in the sucessful production. Thank to the extensive investigations  large amount of the information is available about this fungus, but there are  still questions remaining. One of these questions is the importance of the air in the soil in truffle production. The amount of soil air is one of the most important thing of the soil life, which is in centre of interest. The aim of the investigation was to find out  what kind of effect has the air permeability of soil pores to the  production of truffle. The investigation of aggregate composition has shown the structure of the genetical soil layers, which is in close connection with the air permeability of the soils. We have investigated  basic soil parameters to learn the physical and chemical properties of soil which determine the life conditions of truffle. Water retention capacity and –indirectly–  the differential porosity of the investigated soils were characterized by pF-measurements. The in situ measurement of air permeability of the soils is a rather new technology in our country, and one of our aims was to get acquainted with the method itself. The great advantage of the in situ measurements is that the soils can be investigated in their original structure without disturbance and in this way we can get more exact data about the examined parameter. At the same time the disadvantage is that the measurement cannot be repeated (at the same place). A well-planned measurement protocol can minimize the possibility of the potential mistakes. Our investigations revealed that advanced truffle growing technology should focus not only on nutrient and water supply but on soil air permeability in order to satisfy special needs of these unique fungi.