Mycorrhizas and helper bacteria in growing of willow for energy (Salix viminalis) under conditions of ecological stress

Dr. habil. Piotr Krupa

Professor in Jan Dlugosz University in Częstochowa

Recently we have noticed the problem of exhaustion of non-renewable energy resources. New technologies enable to use new alternative sources of energy. One of promising solution is utilization of plant biomass for energy generation. Growing fast-growing trees and coppice not only supply energy sector in biomass but also is an sustainable alternative for management of abandoned land, post-industrial areas and can serve as habitat for wildlife. Experience of Nordic countries which lasts over 30 years show that under European conditions the best species for this purposes is shrub willow ((Salix viminalis) which is natural element of vegetation, particularly in wetlands. In Poland we are observing that this species is grown for energy in many regions and on different soils – from wet and fertile to dry and poor. We believe that this plantations can be beneficiary from ecological and ecological aspects. Anyway it was observed that many plantations established on arable soils failed or yield level is below profitability level. One of the reasons of this situation can be lack of appropriate pool of specific symbiotic bacteria and fungi in arable soils.

Results f numerous studies performed at Department of Microbiology Jan Dlugosz University in Czestochowa showed that presence of mycorrhizal fungi and helping bacteria is necessary for growth and development of willow for energy. Symbiosis does not mean only improvement of biomass yield (Fig. 1) but sometimes is the only essential conditions for plant establishment in soil which is polluted by many substances including heavy metals (Krupa 2006, Krupa, Jaworska 2007, Krupa 2009, Marczak, Myga, Krupa 2010). The advantage of mycorrhizas is the most pronounced when plants can survive harsh environmental conditions. On areas which we call “difficult to manage” i.e. post-industrial, set-aside etc. symbiotic microorganisms supply higher plants in water and nutrients they can immobilise pollutans and protect roots against pathogens.

References

1. Piotr Krupa (2006) (Bacteria and fungi supporting development of short-rotation willow for energy – in Polish with English summary Bakterie i grzyby wspomagające rozwój wierzby energetycznej (Salix viminalis). Acta Agraria et Silvestria. Vol. XLIX: 297-303

2. Piotr Krupa, Magdalena Jaworska. (2007) Willow (Salix viminalis L.) and bioticfactors affecting its growth under heavy metals stress. Ecological Chemistry and Engineering.vol 14, No 9 : 981-987.

3. Piotr Krupa (2009) (Ectomycorrhizas and its role for plants gropwing at postidustrial degraded land – in Polish with English summary Ektomikoryzy i ich znaczenie dla roślin rosnących na terenach zdegradowanych przez przemysł. Sylwan 153 (3) 189-196.

4. Magdalena Marczak, Magdalena Myga-Nowak, Piotr Krupa. (2010) (Ecological aspects of fungal sybiosis with higher plants – in Polish with English summary Ekologiczne aspekty współżycia roślin z grzybami. Sylwan 154 (4): 234-241

Fig. 1. Average dry weight of willow stems in relation to fungal species used for inoculation (kontrola – means untreated control; wariant szczepienia – means mycorrhizal treatment)