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Genetic variation in silvicultural traits and carbon stock content in a provenance-progeny test of Genipa americana L. (Rubiaceae)

Abstract

The aim of this study was to determine the genetic variation of growth traits, wood basic density, dry mass of crown, leaf, and stem, and carbon stock within and between two Genipa ameri­cana L. provenances. The provenance and progeny test was installed in the Teaching, Research and Extension Farm, located in Selvíria, Mato Grosso do Sul, Brazil. The test was established using a randomized block design with two provenances and 36 progenies, a spacing of 3 x 2 m, four replicates, and six plants per plot. At 11 years of age, height and diameter at breast height (DBH) were measured. To estimate wood basic density, biomass, and carbon stock, 45 plants were thinned. Growth traits for crown, leaf, and stem, as well as wood basic specific gravity showed significant differences. Both provenances pre­sent high carbon storage, demonstrating the potential of this species to be included in carbon credit programs that help to minimize the effects of global warming. In general, heritability values were low, suggesting limited genetic control of the eva­luated traits. However, the traits presented a high coefficient of genetic variation, indicating adequate sampling among popu­lations; these results are promising for ex situ conservation and for future breeding programs.

Open access
Breeding triploid aspen and poplar clones for biomass production

Abstract

Enriched diploid pollen was applied for in vitro pollinations and crossbreeding in the greenhouse to produce high performance triploid aspen and aspen hybrids for cultivation in medium rotation plantations. In addition to crossings within the section Populus, intersectional crossbreeding was performed to combine benefits of intersectional hybridization with those derived from triploidisation.

Both the enrichment of diploid pollen by size fractionation of naturally unreduced pollen and heat treatment of microspore mother cells resulted in a distinct increase of diploid pollen. Using this pollen, six triploid plants were obtained from in vitro pollinations and twenty from crossbreeding in the greenhouse. The triploid plants displayed a high variability in growth performance. Two clones from in vitro pollination and five from crossbreeding in the greenhouse were chosen to estimate growth characteristics. A first assessment of clone performance in an outdoor container test con - ducted over one growing season revealed two triploid clones with a same stem height and a significantly increased basal stem diameter in comparison to the fast-growing triploid reference clone “Astria”. Crossbreeding experiments also resulted in two fast-growing mixoploid clones, which have already been stable for several years.

All in all, in this study, crossbreeding using enriched diploid pollen is proved to be a reliable and applicable approach for an effective breeding of triploid poplars.

Open access
Performance Evaluation of Shrub Willow Clones of North America and Yugoslavia Origins in Jilin, China

Abstract

Demand for planting elite shrub willows as a resource for industrial use such as bioenergy and pulp has been increasing in Jilin province in northeast China. Toward this end, 12 elite willow clones, representing various species and origins, were imported from New York, USA, and planted at Lushui River, Jilin province. Two indigenous species were included in the test as the controls for comparison. This study was an evaluation of their performance in adaptation, growth potential, and wood traits after one rotation (three growing seasons). Results indicated that (1) all clones, but one, showed a parallel phenology to the control, had excellent survival (> 86%) and displayed good frost resistance; (2) compared to the control, most imported clones were comparable in main stem growth (height and diameter), but developed more stems and main roots; and (3) most imported clones had similar lignin, but higher cellulose content relative to the control. These results imply that some of the imported clones should be considered for further evaluation as good sources for both bioenergy and pulping. Based on cluster analysis, six clones were recommended for the upcoming scale-up site-clone trials for yield evaluation.

Open access
Results of an International Provenance Trial of Cordia alliodora in São Paulo, Brazil at Five and 23 Years of Age

Abstract

Cordia alliodora (Ruiz & Pav.) Oken (Boraginaceae) is a tropical timber tree of great economic value that occurs in Latin America and through most of the Caribbean. Genetic variation in growth, form and survival of eight Central America provenances - five from a dry zone and three from a wet zone - were studied five and 23 years after establishment in the state of São Paulo, Brazil. Significant differences between dry and wet zone provenances were detected for diameter at breast height (d.b.h.), stem form and survival and between provenances within these zones for height, d.b.h., volume and survival. Provenances from the dry zone had higher growth rates than those from the wet zone. Genetic correlations among ages for these traits were positive but not significant, while ranking of provenances based on growth and survival changed significantly from five to 23 years of age, indicating that measuring traits at five years of age may not be a good predictor of the same traits at 23 years of age. Genetic correlations on growth traits measured at the same age were large and significant, suggesting substantial gains could be made through indirect trait selection. At 23 years of age the La Fortuna provenance performed best for all traits, while Nueva Guinea performed worst for growth traits and survival and Tres Piedras for stem form. The species’ poor growth compared to that of other tropical tree species at the same experimental site suggests that C. alliodora is not the best silvicultural option for the Luiz Antonio region.

Open access
Myelodysplastic syndrome with myelofibrosis in a 12-year-old patient – A case report

Abstract

Myelodysplastic syndromes are a heterogeneous group of clonal disorders characterized by peripheral blood cytopenia and normal or hypercellular bone marrow with dysplasia in more than one blood cell lineage, unfavorable prognosis, and lack of response to treatment. We present the case of a 12-year-old male patient who was referred to the Hematology and Oncology Department of Pediatric Clinic I Târgu- Mures in May 2016, with splenomegaly and pancytopenia. The osteomedullary biopsy revealed myelofibrosis, discrete dysplasia of the myeloid series and megakaryocytes, blasts CD34+ approximately 10%, which led to the diagnosis of myelodysplastic syndrome with myelofibrosis. The myeloid precursors indicated a high risk of transformation into acute myeloid leukemia, so chemotherapy associated with corticosteroids was started, leading to slight improvements. Although myelodysplastic syndrome associated with myelofibrosis is rare at this age, despite the treatment and favorable progression in the case presented, in the absence of hematopoietic stem cell transplantation the prognosis remains unfavorable.

Open access
Genetic Variation in Growth and Blister-Rust Resistance in a Pinus strobus x P. wallichiana Hybrid Population

Summary

This experiment consists in a controlled crossing according to a factorial design performed between 7 female trees of P. strobus and 4 male trees of P. wallichiana to combine the rapid growth of former species with high resistance to Cronartium ribicola of the latter one. The hybrid families were artificially inoculated at age 2, and field planted at age 6. Blister rust resistance (BRR), tree survival (TS), total height growth, (H) annual height growth (h), diameter (D), basal area (BA), stem volume (V), stems straightness (SS) and branch thickness (BT) were the traits measured at age 17. Statistical analysis produced the results presented below. Significant (p<0.05) and highly significant (p<0.01; p<0.001) differences were found among hybrid families. Differences among female effects were highly significant (p<0.001) for all tested traits including BRR, suggesting that nuclear additive genes controlled these traits. Significant differences were found among male parents for H but no significant differences for BRR; therefore, all four male parents transmitted a similar level of resistance. The ratio σ2 GCA2 SCA variance accounted for 8.1 for BRR, 8.5 for H, 3.5 for V, 9.3 for SS and 1.9 for BT. Similarly, the ratios of σ2 GCA-F2 GCA-M variance due to female parents were 70.5 for BRR, 23.6 for H, 1.0 for V, 0.4 for SS and 1.0 for BT, were found. Narrow-sense heritabilities, at individual level, were low to moderately high, ranging between 0.085 for BT and 0.421 for BRR. By comparison with the mean of P. strobus parent species, the BRR heterosis was highly positive, but negative for all growth traits. If the hybrids will be used in operational planting programs, a significant genetic gain for BRR and growth traits could be achieved.

Open access
Clonal Propagation of Dalbergia sissoo Roxb. by Softwood Nodal Cuttings: Effects of Genotypes, Application of IBA and Position of Cuttings on Shoots

propagation of Vitex negundo L. through leafy stem cuttings from hedged shoots during rainy season. Ind. Perf. 45 (20): 83-87 (2001) HUSEN, A. and PAL, M.: Clonal propagation of Tectona grandis Linn. f. by leafy stem cuttings: effects of branch position and auxin treatment on the rooting ability. Int. Conf. Qua. Tim. Pro. Teak Sus. For. Manag., 2-5 December 2003, Peechi, Kerala State, India (2003b) HUSEN, A.: Effects of IBA and NAA treatments on rooting of Rauvolfia serpentina Benth. ex Kurz shoot cuttings. Ann. For. 11 (1): 88-93 (2003

Open access
Linkage map construction and QTL analysis for Betula platyphylla Suk using RAPD, AFLP, ISSR and SSR

Abstract

A linkage map for Betula platyphylla Suk was constructed based on RAPD, ISSR, AFLP and SSR markers by a pseudo-testcross mapping strategy. A F1 segregating population including 80 progenies was obtained from the cross between two superior trees selected from Qinghai and Wangqing provenance, respectively. The paternal map was constructed with 282 markers consisting of 14 major and 15 minor (5 triplets and 10 doublets) linkage groups and spanning 1131 cM at an average distance of 4.0 cM between adjacent markers. The maternal map has 277 markers consisting of 15 major and 8 minor (5 triplets and 3 doublets) groups covering 1288 cM at an average distance of 4.6 cM between adjacent markers. In the same pedigree we investigated association of genetic markers with seedling stem height and circumference. The composite interval mapping was used to detect the number of quantitative trait loci and their position on the genetic linkage maps. Three QTLs (one on the male map and two on the female map) were found explaining 13.4%, 17.5% and 18.8% of the trait variation, respectively.

Open access
Transcript abundances of LIM transcription factor, 4CL, CAld5H and CesAs affect wood properties in Eucalyptus globulus

Abstract

Eucalyptus globulus is the main hardwood species grown in pulpwood plantations in temperate regions of the world. We have cloned six genes influencing wood quality including the LIM domain transcription factor (LIM), 4-coumarate-CoA ligase (4CL), coniferaldehyde 5-hydroxylase (CAld5H) and the three catalytic units of cellulose synthase (CesA), from E. globulus. The transcript abundances of LIM in basal stems of ten independent E. globulus lines showed similar patterns to those of 4CL. We investigated the correlation between gene transcript abundances and wood qualities such as Klason lignin (KL) content, syringaldehyde/vanillin (S/V) ratio and holocellulose (HC) content. Expression of the LIM and 4CL were positively correlated with KL content. A highly significant positive correlation was observed between CAld5H expression and S/V ratio. Furthermore, a ratio of the sum of the transcript abundances of three CesA1, CesA2 and CesA3 to 4CL showed a positive correlation with a ratio of HC/KL content that positively correlated with the chemically extracted fiber content in this woody plant.

Open access
Genetic Variation of Anatolian Black Pine (Pinus nigra Arnold. subsp. pallasiana (Lamb.) Holmboe) in the Lakes District of Turkey

Abstract

In this study, morphological characteristics of juvenile 1- and 2-year-old seedlings of Anatolian black pine were studied to estimate the amount of genetic variation and heritability of seedling traits of the species in the Lakes District of Turkey. This nursery study involved 460 parent trees from 23 populations in a randomized complete block design. Traits studied were the number and length of cotyledons, hypocotyls and epicotyls lengths, weight and length of initial roots, height, root collar diameter, and stem and root fresh weights, and number of buds. Variation was higher among than within populations with individual tree heritability ranging from 0.09 to 0.76, whereas family mean heritability ranged from 0.16 to 0.80. Genetic and phenotypic correlations between juvenile and 1-year-old seedling traits were generally the same sign and magnitude. Variation and heritabilities were higher for growth-related traits than the number and length of embryonic tissues. The observed level of population differentiation was low, possibly due limited geographic sampling of populations, which spanned only 2° of latitudes and longitudes, and 300m in elevation. If the observed heritabilities for growth traits were sustained to tree maturity combined family and within family selection would be effective in improving growth of this species in the Lakes District of Turkey. A broader geographic sampling is recommended for better estimation of population differentiation and establishment of the geographic pattern of the species in this region.

Open access