Genetic parameters and genotype–environment interactions of Chinese fir (Cunninghamia lanceolata) in Fujian Province

Abstract

Chinese fir (Cunninghamia lanceolata (Lamb.) Hook) is the most commercially important conifer in China, and the Nanjing Forestry University – Fujian Province Chinese fir Cooperation (NJFU – Fujian Cooperation) breeding program has advanced it into the third cycle of selection and breeding. In this paper, we estimated genetic parameters from four sites for 80 half-sib families and summarized previous estimates of genetic parameters in Chinese fir with an objective to propose optimal breeding strategy. Heritability averaged 0.20 and 0.14 for height and diameter at breast height (DBH), respectively, for the four sites. A significant genotype–environment interaction (G × E) for growth was also observed among the four sites, with the greatest interactions between a marginal site and the three central sites in the Fujian Province Chinese fir plantation region. The average estimated type-B genetic correlation between the marginal site and the three central sites was 0.08 for height and –0.09 for DBH. However, the highly productive families were among the most stable across the four sites. The results from this study in combination with summarized genetic parameters from literature were used to discuss and propose an optimal breeding strategy for the third generation of the breeding program for Chinese firs in Fujian Province.

Assessing 62 Chinese Fir (Cunninghamia lanceolata) Breeding Parents in a 12-Year Grafted Clone Test

“…Bian et al [12] reported that the Chinese fir repeatability of H, DBH and WBD traits in clonal tests ranged from 0.63-0.79, 0.49-0.78, and 0.51-0.75, respectively. Our report showed a high estimated repeatability for these traits (Table 1).…”

“…Similar to other conifer breeding programs around the world, the improvement of Chinese fir mainly emphasizes the enhancement of growth and adaptability with the following activities: provenance testing, plus-tree selection, establishment of breeding garden/gene bank, family/progeny (half-sib and full-sib) and clonal testing, parent tree (plus-tree clone) reselection, clonal seed orchard establishment, and so forth [12]. Wood quality traits were recently targeted as a breeding objective due to increasing demands for high-quality timber in the last 10 years.…”

Genotypic variation of Cunninghamia lanceolata revealed by phenotypic traits and SRAP markers

“…H, height; DBH, diameter at breast height; V, stem volume; WBD, wood basic density; Hy, hygroscopicity; HR, heart-wood ratio; TL, tracheid length; TD, tracheid diameter; TLDR, tracheid length-diameter ratio; SD, standard deviation; F, the ANO-VA (analysis of variance) parameter F (*p < 0.05, **p < 0.01); CV, coefficient of variation; R, repeatability tions in southern China (Shi et al 2010). Based on the knowledge and availability of genetic variability for selection (Bian et al 2014), remarkable successes in breeding have already been achieved for this species, e.g. large-scale collection of elite germplasms, establishment of first and second and third generation seed orchards, and significant gains of superior clones.…”

Spatial analysis increases efficiency of progeny testing of Chinese fir

“…The incomplete block design was generally effective in Fujian's hilly Chinese fir sites. These sites typically have environmental gradients from hill top to bottom (Bian et al 2014). To reduce this global trend of environmental variation, blocks were usually employed along the contour of the site to keep the microenvironment within the same block as homogeneous as possible.…”

“…Breeding for growth traits in the first two generations has increased average growth rate by almost 30% (Shi 1994). In a quantitative genetics survey, several unusual and interesting unique genetic properties of Chinese fir's breeding population such as low heritability of wood density and low negative genetic correlation between growth and wood density, a large difference between narrow-sense and broad-sense heritability, and regional-related G by E interactions were found (Bian et al 2014). Several relatively large progeny trials with a family of sufficient size for genetic analyses revealed low heritability for DBH (e.g., h 2 = 0.09 in a trial of 112 families (Fang and Shi 1998); h 2 = 0.05 in another trial of 228 families (Yu et al 2001)).…”