Genetic improvement of sawn-board shape stability in Scots pine (Pinus sylvestris L.)

Adequate shape stability is a prerequisite for utilization of sawn boards in the building industry. This study investigated the possibility of indirect genetic improvement of Scots pine (Pinus sylvestris L.) sawn-board shape stability (specifically the bow, crook and twist) via selective breeding based on traits that can be non-destructively measured on standing trees. Relationships between shape stability and wood quality traits measured on logs and sawn boards were also determined. A total of 1896 standing trees from a 39-year-old Scots pine full-sib progeny test were non-destructively measured. A subset of 496 trees was harvested and sawn into 50 x 100 mm boards, the quality of which was assessed both non-destructively and destructively. Among the traits assessed on standing trees, grain angle (GRA) appeared to be the best predictor of sawn-board twisting and crooking (r(A) = 0.84 and 0.62, respectively). The individual-tree narrow-sense heritability (h(i)(2)) was moderate for twist and GRA (0.37 and 0.40, respectively), low for bow (0.21) and very low for crook (0.05). Selective breeding targeting lower GRA would result in lower twist and crook but could also increase sawn-board density, stiffness and strength

Prevention or early cure of type 1 diabetes by intranasal administration of gliadin in NOD mice

Induction of long-term tolerance to β-cell autoantigens has been investigated both in animal models and in human type 1 diabetes (T1D) in order to prevent the disease. As regards external compounds, the dietary plant protein fraction has been associated with high penetrance of the disease, whereas gluten-free diets prevent T1D in animal models. Herewith we investigated whether intranasal (i.n.) administration of gliadin or gluten may arrest the diabetogenic process. I.n. administration of gliadin to 4-week-old NOD mice significantly reduced the diabetes incidence. Similarly, the insulitis was lowered. Intranasal gliadin also rescued a fraction of prediabetic 13-week-old NOD mice from progressing to clinical onset of diabetes compared to OVA-treated controls. Vaccination with i.n. gliadin led to an induction of CD4(+)Foxp3(+) T cells and even more significant induction of γδ T cells in mucosal, but not in non-mucosal lymphoid compartments. This prevention strategy was characterized by an increased proportion of IL-10 and a decreased proportion of IL-2, IL-4 and IFN-γ-positive CD4(+)Foxp3(+) T cells, and IFN-γ-positive γδ T cells, preferentially in mucosal lymphoid organs. In conclusion, i.n. vaccination with gliadin, an environmental antigen with possible etiological influence in T1D, may represent a novel, safer strategy for prevention or even early cure of T1D

Gluten-Free Diet Only during Pregnancy Efficiently Prevents Diabetes in NOD Mouse Offspring

Studies have documented that the pathogenesis of autoimmune diabetes is influenced by the intake of gluten. Aims. To investigate the importance of gluten exposure during pregnancy and the subsequent development of autoimmune diabetes in offspring. Methods. Nonobese diabetic mice were divided into 7 groups to receive combinations of gluten-free and standard diet before, during, or after pregnancy. Diabetes incidence in offspring was followed in each group (n=16–27) for 310 days. Insulitis score and intestinal expression of T-cell transcription factors (RT-QPCR) were evaluated in animals from the different diet groups. Results. If mothers were fed a gluten-free diet only during pregnancy, the development of autoimmune diabetes in offspring was almost completely prevented with an incidence reduction from 62.5% in gluten-consuming mice to 8.3% (p<0.0001) in the gluten-free group. The islets of Langerhans were less infiltrated (p<0.001) and the intestinal expression of RORγt (Th17) (p<0.0001) reduced in mice whose mothers were Gluten-free during pregnancy. Conclusion. A gluten-free diet exclusively during pregnancy efficiently prevents autoimmune diabetes development in offspring and reduces insulitis and intestinal expression of RORγt (Th17)

Impact of Dietary Gluten on Regulatory T Cells and Th17 Cells in BALB/c Mice

Dietary gluten influences the development of type 1 diabetes (T1D) and a gluten-free (GF) diet has a protective effect on the development of T1D. Gluten may influence T1D due to its direct effect on intestinal immunity; however, these mechanisms have not been adequately studied. We studied the effect of a GF diet compared to a gluten-containing standard (STD) diet on selected T cell subsets, associated with regulatory functions as well as proinflammatory Th17 cells, in BALB/c mice. Furthermore, we assessed diet-induced changes in the expression of various T cell markers, and determined if changes were confined to intestinal or non-intestinal lymphoid compartments. The gluten-containing STD diet led to a significantly decreased proportion of γδ T cells in all lymphoid compartments studied, although an increase was detected in some γδ T cell subsets (CD8+, CD103+). Further, it decreased the proportion of CD4+CD62L+ T cells in Peyer's patches. Interestingly, no diet-induced changes were found among CD4+Foxp3+ T cells or CD3+CD49b+cells (NKT cells) and CD3−CD49b+ (NK) cells. Mice fed the STD diet showed increased proportions of CD4+CD45RBhigh+ and CD103+ T cells and a lower proportion of CD4+CD45RBlow+ T cells in both mucosal and non-mucosal compartments. The Th17 cell population, associated with the development of autoimmunity, was substantially increased in pancreatic lymph nodes of mice fed the STD diet. Collectively, our data indicate that dietary gluten influences multiple regulatory T cell subsets as well as Th17 cells in mucosal lymphoid tissue while fewer differences were observed in non-mucosal lymphoid compartments

Quantitative genetics of wood quality traits in Scots pine

Wood quality of commercial tree species is important for many wood processing industries and thus should be considered for inclusion in forest tree improvement programs. This thesis evaluated the suitability of various proxy methods for rapid and non-destructive assessment of wood quality traits on standing trees of Scots pine and the potential for genetic improvement of different wood quality traits through recurrent selective breeding. Penetrometer Pilodyn and micro-drill Resistograph were tested for non-destructive assessment of wood density (DENPIL and DENRES, respectively), using SilviScan density (DENSILV) as a benchmark. A strong additive genetic correlation was observed between DENSILV and DENRES (rA = 0.96), whilst the correlation with DENPIL was substantially lower (rA = 0.74). Furthermore, SilviScan stiffness (MOESILV) was used as a benchmark for evaluation of several approaches of calculating the dynamic modulus of elasticity (MOE) from standing-tree acoustic velocity (VELTREE). The combination of VELTREE and adjusted DENRES provided the most accurate estimate of MOETREE (rA = 0.91). Additionally, non-destructive acoustic sensing tools were tested at different stages of wood processing (on standing trees, felled logs and sawn boards) using destructively measured sawn-board stiffness (static modulus of elasticity, MOES) and strength (modulus of rupture, MOR) as benchmarks. They proved to be capable of accurately predicting MOES (rA ≈ 0.8) while VELTREE, adjusted DENRES and MOETREE well reflected MOR (rA ≈ 0.9). Genetic variation of shape stability of sawn boards (bow, crook and twist) was also investigated. Under-bark grain angle (GRA) was found to be a good predictor of sawn-board twisting and crooking (rA = 0.84 and 0.62, respectively). The chemical composition of juvenile wood (proportion of cellulose, hemicelluloses, lignin and extractives) was predicted from Fourier transform infrared (FTIR) spectra using partial least squares regression (PLSR) modeling. Individual-tree narrow-sense heritabilities (ℎi2) for all of the studied wood quality traits varied from low to moderate. Genetic improvement of sawn-board DEN, MOES and MOR as the target traits could be achieved through selective breeding for MOETREE, DENRES, stem straightness (STR) or GRA. Selection focusing on GRA would also result in lower bow, crook and twist. Despite the negative genetic correlations between growth and wood quality traits, a possibility of their simultaneous improvement was identified. An index combining stem diameter (DBH) and MOETREE provided the best compromise

Genetic Improvement of Sawn-Board Stiffness and Strength in Scots Pine (Pinus sylvestris L.)

Given an overall aim of improving Scots pine structural wood quality by selective tree breeding, we investigated the potential of non-destructive acoustic sensing tools to accurately predict wood stiffness (modulus of elasticity, MOE) and strength (modulus of rupture, MOR) of sawn boards. Non-destructive measurements of wood density (DEN), acoustic velocity (VEL) and MOE were carried out at different stages of wood processing chain (standing trees, felled logs and sawn boards), whilst destructively measured stiffness and strength served as benchmark traits. All acoustic based MOE and VEL estimates proved to be good proxies (r(A) > 0.65) for sawn-board stiffness while MOETREE, VELHIT and resistograph wood density (DENRES) measured on standing trees and MOELOG and VELFAK measured on felled logs well reflected board strength. Individual-tree narrow-sense heritability (hi2) for VEL, MOE and MOR were weak (0.05-0.26) but were substantially stronger for wood density (0.34-0.40). Moreover, additive genetic coefficients of variation for MOE and MOR were in the range from 5.4% to 9.1%, offering potential targets for exploitation by selective breeding. Consequently, selective breeding based on MOETREE, DENRES or stem straightness (STR) could improve several structural wood traits simultaneously

Genetic improvement of the chemical composition of Scots pine (Pinus sylvestrisL.) juvenile wood for bioenergy production

Chemical composition is one of the key characteristics that determines wood quality and in turn its suitability for different end products and applications. The inclusion of chemical compositional traits in forest tree improvement requires high-throughput techniques capable of rapid, non-destructive and cost-efficient assessment of large-scale breeding experiments. We tested whether Fourier-transform infrared (FTIR) spectroscopy, coupled with partial least squares regression, could serve as an alternative to traditional wet chemistry protocols for the determination of the chemical composition of juvenile wood in Scots pine for tree improvement purposes. FTIR spectra were acquired for 1,245 trees selected in two Scots pine (Pinus sylvestrisL.) full-sib progeny tests located in northern Sweden. Predictive models were developed using 70 reference samples with known chemical composition (the proportion of lignin, carbohydrates [cellulose, hemicelluloses and their structural monosaccharides glucose, mannose, xylose, galactose, and arabinose] and extractives). Individual-tree narrow-sense heritabilities and additive genetic correlations were estimated for all chemical traits as well as for growth (height and stem diameter) and wood quality traits (density and stiffness). Genetic control of the chemical traits was mostly moderate. Of the major chemical components, highest heritabilities were observed for hemicelluloses (0.43-0.47), intermediate for lignin and extractives (0.30-0.39), and lowest for cellulose (0.20-0.25). Additive genetic correlations among chemical traits were, except for extractives, positive while those between chemical and wood quality traits were negative. In both groups (chemical and wood quality traits), correlations with extractives exhibited opposite signs. Correlations of chemical traits with growth traits were near zero. The best strategy for genetic improvement of Scots pine juvenile wood for bioenergy production is to decrease and stabilize the content of extractives among trees and then focus on increasing the cellulose:lignin ratio

Non-destructive wood density assessment of Scots pine using Resistograph and Pilodyn

Dataset used in article "Non-destructive wood density assessment of Scots pine (Pinus sylvestris L.) using Resistograph and Pilodyn