The growth rhythm and height growth of seedlings of Siberian (Larix sibirica Ledeb.) and Dahurian (Larix gmelinii Rupr.) larch provenances in greenhouse conditions

Abstract

The aim of this study was to determine whether the growth rhythm and height growth differ between various larch provenances grown in greenhouse conditions. We also investigated whether the geographic and climatic conditions at the origin of the provenance could explain the possible differences between the provenances. The study material consisted of 16 Russian Siberian (Larix sibirica Ledeb.) and Dahurian larch (Larix gmelinii Rupr.) provenances and four seed sources from Finland as comparison lots. The growth rhythm differences were clearest between the southern and northern provenances; the southern provenances grew for a longer period and the proportion of late summer height growth was larger. Autumn colouration also developed later in these provenances. In the Russian larch material the provenances with a longer growing period had greater height growth. In the whole material the relationship was not so linear due to the deviating behaviour of the comparison material. Several of the Russian larch provenances were taller than the Finnish comparison seed lots, although the difference was not statistically significant. However, the growth of these provenances must be followed for a much longer period in field trials before any conclusions can be drawn about their usability in practical forestry.

Survival, height growth and damages of Siberian (Larix sibirica Ledeb.) and Dahurian (Larix gmelinii Rupr.) larch provenances in field trials located in southern and northern Finland

“…Interpolation was made by averaging two to four of the closest value points, depending on the location of the seed source in relation to available grid points (if deviation < 0.05 degrees, nearest value was used). This approach provided consistent values with the temperature sum map published by Tuhkanen (1984) and also improved the accuracy of climatic information used previously by Lukkarinen et al (2009).…”

“…provenances ( In our work the species concept and nomenclature follow those of Farjon (1990) and Hämet-Ahti et al (1992). The same research material has also been used and described in more detail by Lukkarinen et al (2009), who analysed the growth rhythm and height growth of seedlings in Siberian and Dahurian larch provenances in greenhouse conditions.…”

“…In autumn 2005, the seedlings grown in the greenhouse over one growing season (see Lukkarinen et al 2009) (Table 3), excluding Kivalo site 2 which was not done in 2009, because of its poor condition. On the harrowed Kivalo site 2 the seedlings suffered much more because of competition from other vegetation, and possibly also on the generally poorer growing conditions, than on the ploughed site 1.…”

“…In 2007 in Punkaharju, the average height of the seedlings had doubled from 31 cm in the greenhouse (Lukkarinen et al 2009) to 76 cm (Table 4). In Kivalo, after two years in the field, the average height was still the same than in the greenhouse.…”

“…Provenance test sites with the same material have been established in Sweden, Norway, Iceland, Russia, France, Japan, China, Canada and the United States (Martinsson and Lesinski 2007). This work is also a follow-up study to Lukkarinen et al (2009) research into the growth rhythm and height growth of seedlings of the same larch provenance material in greenhouse conditions.…”