The effect of nursery substrate and fertilization on the growth and ectomycorrhizal status of containerized and outplanted seedlings of Picea abies

Abstract

Raulí (Nothofagus nervosa) is a highly valuable and fast growing Chilean native tree species, therefore being of great interest for the establishment of plantations. The success of plantations depends upon several factors, among which nursery management can be decisive. This study evaluated the effects of slow release fertilization (FLC) in doses of 2.5, 5.0 and 7.5 kg m-3 , and of topping (with and without) on the survival and growth of raulí in a plantation with restoration purposes in the Valdivian Andes of Chile (650 m asl). Average survival was 82 % the first year, 70 % the second and 62 % the third (mortality due to frosts). The mean height growth for the period was 120 cm. However, the trend was that survival and growth were greater with the two higher fertilization doses, and to a lesser extent with topping. During the first three years of field evaluation we did not detect significant differences of FLC and top pruning on survival, height growth and diameter at breast height among the six treatments. However, the trend was that there were higher survival rates and growth rates with the two higher FLC doses, which also occurred with top pruning (better perforrmance with pruning), but to a lower extent. Results show that with the range of plant quality used, similar performance results can be obtained when outplanted in the field. RESUMEN Nothofagus nervosa (raulí) es una de las especies nativas chilenas de mayor valor y crecimiento y, por ello, en el último tiempo concita alto interés para el establecimiento de plantaciones. El éxito del establecimiento de plantaciones depende de diversos fac-tores, entre los cuales el manejo en vivero puede ser decisivo. El presente estudio evaluó los efectos de fertilización de liberación controlada (FLC en dosis de 2,5, 5,0 y 7,5 kg m-3) y de poda apical (con y sin) en vivero sobre la supervivencia y el crecimiento de N. nervosa en plantaciones con fines de restauración en Los Andes valdivianos de Chile (650 m s.n.m.). La supervivencia fue de 82 % en el primer año, 70 % en el segundo y 62 % en el tercero (mortalidad por heladas). El crecimiento promedio en altura durante el trienio estuvo alrededor de 120 cm. Durante los primeros tres años de evaluación en terreno no se observaron efectos significativos de las dosis de FLC y la poda sobre la supervivencia, crecimientos en altura y en diámetro a la altura del pecho. Sin embargo, la tendencia fue de mayor supervivencia y crecimiento con ambas dosis mayores de FLC, lo cual también ocurrió con poda apical, pero en menor magnitud. Los resultados demuestran que en el rango de calidad de planta obtenida en vivero se pueden alcanzar similares resultados en terreno. Palabras clave: restauración, estrés abiótico, mortalidad, crecimiento.

Mycorrhization, establishment and growth of outplanted Picea abies seedlings produced under different cultivation systems

“…Results of those studies suggest that A. byssoides is an efficient root coloniser of P. abies seedlings. Its common occurrence in newly established forest plantations (Kranabetter J 2004, Menkis et al 2007, Vaario et al 2009), and better survival of abundantly colonised CR seedlings of the present study further suggest that A. byssoides may play an important role in seedlings survival and establishment following their outplanting. In support to this, Jones et al (2009) showed that 15 N accumulation in shoots and roots of spruce seedlings colonised by A. byssoides was respectively moderate and high compared to the seedlings colonised by other ECMs.…”

“…In a related Finnish study, Vaario et al (2009) reported that containerised P. abies seedlings grown in a similar substrate and with similar mycorrhization levels as CR seedlings, although produced satisfactory shoot growth in the nursery showed reduced growth rates after transfer to the field. Similar growth patterns, when P. abies seedlings with most abundant ECM colonisation showed reduced rates of height increment were observed in the study conducted on replanted forest clear-cut (Menkis et al 2010).…”

“…Moreover, beneficial effects of ECM fungi are likely to be most pronounced on poor fertility planting sites under harsh environmental conditions (Smith and Read 1997). Vaario et al (2009) suggested that ECMs on roots of containerised P. abies nursery seedlings was one of the best indicators of seedling performance after outplanting. In their study, A. byssoides has undergone a relatively rapid expansion from marginal levels of occurrence in the nursery seedlings to moderate levels in the third year seedlings after outplanting.…”

Effects of substrate and ectomycorrhizal inoculation on the development of two-years-old container-grown Norway spruce (Picea abies Karst.) seedlings

“…One of the growth media most utilized for growing containerized plants is peat, used either alone or as a main component of peatbased growing mixtures (Landis et al 1990, Vaario et al 2009, Heiskanen 2013. Especially light low-humified Sphagnum peat has the required attributes (such as low pH, high cation exchange capacity, low inherent fertility, a proper balance of aeration and waterholding porosity) and provides reasonable growth conditions in the greenhouse (Landis et al 1990, Heiskanen 1993.…”

Leaf number indicates salt tolerance of young seedling families of European aspen (Populus tremula L.) growing in different soils

“…Rytter et al (2003) investigated the field performance of containerized seedlings of silver birch and Norway spruce and suggested that shoot length was of lesser importance to future growth than a high root/ shoot ratio, which is of known importance in the growth of other conifers. Furthermore, it has been reported that the production of new roots can rapidly alleviate the reduced growth of seedlings caused by transplant shock (Davis and Jacobs 2005) and improve nutrient uptake by supporting more ectomycorrhizal fungi (Vaario et al 2009). The fact that aspen seedlings have more roots in forest soil than in sandy soil (corresponding to higher root/shoot ratio) could also be explained by the higher amount of organic matter in the former.…”