Inheritance of basic density and microfibril angle and their variations among full-sib families and their parental clones in Picea glehnii

Abstract

Picea glehnii is one of the most important plantation species in Hokkaido, Japan. Basic density (BD) and microfibril angle (MFA) of the S2 layer in latewood tracheid in 16 full-sib families and their six parental clones planted in Hokkaido were examined to clarify among-family and clonal variations of wood properties and their inheritance from parents to offspring. Mean values of BD and MFA in full-sib families and parental clones were 0.36 and 0.35 g cm-3 and 16.1° and 10.7°, respectively. Estimated repeatabilities of BD and MFA in juvenile wood (jW) were higher than those in mature wood. In addition, larger genetic coefficient of variation was detected for jW, indicating that improvement of jW properties is important to Hokkaido’s tree breeding program. Parent-offspring correlation coefficients were positive and significant in all properties. These results suggest that the influence of parental clones on wood properties is inheritable to offspring. Moreover, there were no significant differences between reciprocal crosses of wood properties, suggesting that plus-tree clones with good wood properties can be used as either female or male parents for producing offspring. There is a possibility of improving wood properties in P. glehnii by crossing clones with desirable properties.

Within-tree radial and among-family variations in wood density, microfibril angle, and mechanical properties in <i>Picea glehnii</i>

“…This trend is also observed in P. glehnii. In a previous study, the clonal mean value of MFA in P. glehnii decreased from the pith (approximately 18°) until the 20th annual ring and became almost constant at approximately 8° (Tanabe et al 2015). In the present study, similar values of MFA were observed, although the annual ring number at which the radial variation of MFA became stable was slightly different from that reported by Tanabe et al (2015).…”

“…Correlation coefficients (r) between ARW and wood properties were separately calculated for juvenile and mature woods. In this study, the boundary between juvenile and mature woods was assumed at the 15th annual ring from the pith according to a previous report on P. glehnii (Tanabe et al 2015). Age-age correlation of each wood property was determined by calculating correlation coefficients between mean values from pith to bark and values at each radial position.…”

“…In general, the within-tree radial variation of MFA shows a decreasing trend from the pith until the 15th-20th annual ring and then stabilizes toward the bark in Picea species (Alteyrac et al 2006a;Gräns et al 2009;Lenz et al 2010;Tanabe et al 2015Tanabe et al , 2017 and other conifers (Panshin and de Zeeuw 1980;Bendtsen and Senft 1986;Zobel and van Buijitenen 1989). This trend is also observed in P. glehnii.…”

“…In tree breeding for the improvement of wood quality in P. glehnii, variations in wood properties have been investigated mainly among plus-tree clones (Akutsu and Iizuka 1998;Iizuka et al 1999Iizuka et al , 2000. In contrast, information regarding among-family variations of wood properties in P. glehnii is limited (Iizuka et al 2001;Tanabe et al 2015). Lenz et al (2011) pointed out that the optimal age of which selection maximizes genetic gain might vary because the contribution of genetic factors to wood properties varies with radial direction.…”

Variation in the Microfibril Angles in Resonance and Non-Resonance Spruce Wood (Picea abies [L.] Karst.)

“…The arrangement of microfibrils in this layer has a significant influence on wood properties (Alteyrac et al 2006;Xu et al 2011). The angle of cellulose microfibrils in the S2 layer is a genetic feature that can be modified by external factors related to the habitat and conditions of tree growth (Lindström et al 1998;Abe and Funada 2005;Tanabe et al 2015). The microfibril angle (MFA) can vary also within individual annual rings.…”