Inoculation of Pinus halepensis Mill. with selected ectomycorrhizal fungi improves seedling establishment 2 years after planting in a degraded gypsum soil

Abstract

Vegetative inoculum of Amanita ovoidea (Bull.) Link and three isolates of Suillus collinitus (Fr.) Kuntze, as well as spore inoculum of Rhizopogon roseolus (Corda) Th. M. Fr. and S. collinitus, were evaluated for the production of Pinus halepensis Mill. in nursery and for the establishment of seedlings in a degraded gypsum soil. In nursery, most of the fungi significantly improved the height of seedlings and modified the accumulation of nutrients in needles. The percentage of ectomycorrhizas (ESR) per seedling ranged from 25 to 78%, depending on the fungi. One and 2 years after planting in the field, the survival of seedlings was significantly improved by inoculation with two isolates of S. collinitus and with spores of the same fungus. Inoculation with A. ovoidea had no significant effect on seedling survival, whilst R. roseolus caused a significant mortality of seedlings. Seedling height was significantly improved by inoculation with all fungi except R. roseolus and isolate CCMA-1 of S. collinitus. One year after planting, mycorrhization of control seedlings was negligible, and percentages of ESR were under 38% for the rest of treatments. In spring of the second year, seedlings in all treatments, including the control, became highly mycorrhizal (60-77% of ESR). Low ectomycorrhizal diversity (five morphotypes described) and seasonal variation on morphotype composition were detected 2 years after plantation. From a perspective of soil restoration management under limiting environmental conditions, nursery inoculation with selected fungi can be a key advantage for tree seedlings to surmount the initial transplant stress, assuring their establishment in the field. Our results emphasise the importance of selecting compatible fungal-host species combinations for nursery inoculation and sources of inoculum adapted to the environmental conditions of the transplantation site.

Mycorrhization of containerized Pinus nigra seedlings with Suillus granulatus under open field conditions

“…Under the semi-arid Mediterranean environmental conditions, S. collinitus is thought to be a suitable and lasting inoculant for Pinus halepensis Mill. and Pinus pinaster Aiton (Tores and Honrubia, 1994;Pera and Parlade, 2005;Ruiz-Diez et al, 2006;El Karkouri et al, 2006;Rincon et al, 2007). S. granulatus has been used for mycorrhization of P. ponderosa Douglas ex C. Lawson and P. contorta Douglas seedlings in North America (Riffle and Tinus, 1982;Clein and Reid, 1982) and for P. halepensis in Spain (Rincon et al, 2005;Pera and Parlade, 2005).…”

“…Mycorrhiza improves the mineral nutrition, growth, and adaptation of forest trees; therefore, seedling mycorrhization is thought to be among the most important tools for achieving higher seedling quality (Molina, 1979;Pera and Parlade, 2005;Ruiz-Diez et al, 2006;Rincon et al, 2007). In Montenegrin and Serbian nurseries, controlled mycorrhizal inoculation of seedlings has yet to become common practice, and the fungi and fungal isolates from this region have not been examined previously as the material for mycorrhization.…”

Mycorrhization, growth and nutrition of Pinus halepensis seedlings fertilized with different doses and sources of nitrogen

“…This species plays a critical role in the restoration of degraded lands under adverse climate and soil conditions. Several studies report the beneficial effect of mycorrhizal inoculation on field performance in P. halepensis (Díaz et al, 2004;Parladé et al, 2004;Querejeta et al, 1998;Rincón et al, 2007a;Roldan et al, 1996).…”

The combined effects of Pseudomonas fluorescens CECT 844 and the black truffle co-inoculation on Pinus nigra seedlings

“…Rincón et al (2007) observed different effects of ectomycorrhizal fungi on the nutrient uptake in seedlings of P. halepensis, as a likely consequence of nutritional demands that were dependent on the fungal species (Olsson et al 2002). Also, in our previous studies on T. melanosporum, inoculation was shown to improve growth and nutrition, particularly in P. halepensis seedlings (Domínguez et al 2008(Domínguez et al , 2012.…”

“…In some cases, the co-inoculation of mycorrhizal fungi and P. fluorescens may also increase the root colonization by Pseudomonas (Ouahmane et al 2009, Dominguez et al 2012, and the mycorrhizal fungus. In other cases, synergistic effects on the plant growth were observed (Rincón et al 2007), although co-inoculation did not affect the fungal colonization.…”