Evaluation of reference genes and characterization of the MYBs in xylem radial change of Chinese fir stem

The radial change (RC) of tree stem is the process of heartwood formation involved in complex molecular mechanism. Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.), an evergreen species, is an important fast-growing timber tree in southern China. In this study, the top four stable genes (IDH, UBC2, RCA and H2B) were selected in RC tissues of 15 years old Chinese fir stem (RC15) and the genes (H2B, 18S, TIP41 and GAPDH) were selected in RC tissues of 30 years old Chinese fir stem (RC30). The stability of the reference genes is higher in RC30 than in RC15. Sixty-one MYB transcripts were obtained on the PacBio Sequel platform from woody tissues of one 30 years old Chinese fir stem. Based on the number of MYB DNA-binding domain and phylogenetic relationships, the ClMYB transcripts contained 21 transcripts of MYB-related proteins (1R-MYB), 39 transcripts of R2R3-MYB proteins (2R-MYB), one transcript of R1R2R3-MYB protein (3R-MYB) belonged to 18 function-annotated clades and two function-unknown clades. In RC woody tissues of 30 years old Chinese fir stem, ClMYB22 was the transcript with the greatest fold change detected by both RNA-seq and qRT-PCR. Reference genes selected in this study will be helpful for further verification of transcript abundance patterns during the heartwood formation of Chinese fir.

Inventory of Dryobalanops aromatica Gaertn. in Lae Kombih Forest Park Area, Subulussalam

Dryobalanops aromatica Gaertn. is a plant that grows in the tropical rain forests of western Indonesia which is categorized as a valuable timber tree. Dryobalanops aromatica Gaertn is a plant that is categorized as a valuable timber tree. Dryobalanops aromatica Gaertn also known as the camphor tree, lime or Sumatran camphor, this tree can grow to a height of 60 m with an average trunk diameter of 9 m. Camphor tree is a plant species belonging to the Dipterocarpaceae family which has several advantages because its tree trunk can produce a variety of high economic value commodities such as camphor, balsamic acid, resin, essential oil, beams, poles, roof construction and boards in residential buildings. The method used for the inventory of rare plants is done by using the method of vegetation analysis, the parameters in this study were the type, number, diameter and height of the Dryobalanops aromatica Gaertn. tree. Vegetation analysis was carried out by plotting 13 plots, each sample plot measuring 20 m x 20 m. The sample used is a total sample using a random sampling system method, the sampling chossen by exploring the area of the Tahura Lae Kombih area where the Dryobalanops aromatica Gaertn is located. The results shows that the plant species were found starting from the seedling, sapling, pole and tree levels. The most dominant species in this area is Dryobalanops aromatica Gaertn that has Important Value Indeks of seedling 163%, Sapling 270%, Pole 283% and Tree 216%.

A COMPARISON OF METABOLITES IN WOOD-FORMING TISSUES FROM EIGHT COMMERCIAL TIMBER TREE SPECIES OF HEILONGJIANG PROVINCE IN CHINA

Four coniferous and four deciduous commercial tree species from Northeastern ofChina were selected to investigate the differences ofmetabolites in wood-forming tissues bygas chromatography-mass spectrometry. The results showed that the identified metabolites mainly consisted of neutral sugars, lipids, and organic acids. The mean contents of both arabinofuranose and 1-cyclohexene-1-carboxylic acid were higher in coniferous trees thanin deciduous ones. Similarly, the D-fructose and D-glucose content was significantly higherin coniferous trees than deciduous trees, but the total contents of these two sugars was roughly equal among most tree species. The mean content of lactic acid, glycerol and malic acid was lowerin coniferous trees than deciduous trees. The malic acid content decreased in later-stages of wood formation than in early-stagefor all tree species. The content of L-proline and myo-inositol was greater in later-stage of wood formation than early-stage.The contentof octadecanoic acid, D-fructose and D-glucose decreased in later-stage of wood formationfor most tree species. All of thissuggested that the metabolites in wood-forming tissues showed the significance of species-specific and seasonal dynamic differences among the eight tree species.

Preliminary assessment of ironwood (Eusideroxylon zwageri Teijsm. & Binnend.) stand on the KPPN Bulian of the District VIII of PT. Wirakarya Sakti, Jambi as seed source candidate

Ironwood (Eusideroxylon zwageri) is one of Indonesia’s most economically valuable timber tree species and was listed as Vulnerable in 1998 by the IUCN. To support conservation activities and establish E. zwageri’s plantation, good quality planting stocks should be collected from specific seed sources. Currently, there is only one ironwood seed source in Sumatra that has been registered. This study aimed to assess the potential for an ironwood stand on the KPPN Bulian of the District VIII of PT. Wirakarya Sakti is to be proposed as a seed source. The assessment was conducted on July 2020 by a 100% inventory of ironwood trees in the area of 43 ha. Every individual tree and copy of ironwood was measured for its stem diameter and tree height and observed for its health, flowers, fruits, and seedlings in the ground. In total, 1,029 individual trees, copies and seedlings were recorded. Among them, 116 trees were found to have young fruits and seedlings emergence in the forest floor. Generally, the ironwood stand is sound and meets the criteria to be registered as an identified seed stand of ironwood.

A Review: Prospective study of non-timber forest product uses in three Meranti species (Shorea spp.)

Meranti (Shorea spp.) is a commercial timber tree species of Indonesian forest potentially to be developed for Non-Timber Forest Products (NTFPs). We explored the NTFPs perspective of three Meranti species, Shorea hopeifolia (F.Heim) Symington, Shorea ovalis (Korth.) Blume, and Shorea balangeran Burk, by identifying the content of phytochemical compounds. Data collection methods include: exploration, identification to obtain the accuracy of the species scientific name, and analysis the phytochemical content using Gas Chromatographic Mass Spectrometer (GCMS) pyrolysis. We revealed the bark of the tree species contained phytochemical compounds potential for medicinal ingredients especially for antidiabetic, antioxidant, and anticancer. Since the exploitation of the bark is better than the trees, the potential use of non-timber forest products of the meranti supports the conservation of the species. Further research to unveil other benefits of the meranti species should be conducted.

High Genetic Diversity of Shorea acuminata Dyer in the Rehabilitated Area of a Degraded Lowland Dipterocarp Tropical Rainforest

The United Nation’s Decade on Ecosystem Restoration 2021–2030 aims to halt ecosystem degradation to achieve Sustainable Development Goals (SDGs) by 2030. In Malaysia, the concept of sustainable forest management (SFM) has been practiced since 1901. In this study, we evaluated the genetic diversity of the native dipterocarp timber tree Shorea acuminata in a rehabilitated area at Kenaboi Forest Reserve (Kenaboi FR). The rehabilitated area was formerly a degraded forest managed with the taungya restoration system for 50 years. All trees with diameter at breast height (DBH) of 5 cm and over were measured, tagged and identified in a one-hectare study plot. A total of 132 inner bark samples were collected for DNA extraction. Four SSR markers (Sle280, Sle392, Sle475 and Sle566) and two EST-SSR markers (SleE07 and SleE16) were used to analyse 95 good-quality DNA samples. Genetic diversity parameters including maternal contribution were determined for 75 samples. The genetic diversity of big trees (He = 0.656 ± 0.19) and small trees (He = 0.652 ± 0.17) were high and both were in genetic equilibrium, with Fis values of the big trees being 0.035 and small trees being 0.164. Clustering analysis based on Jaccard’s similarity values (at 95% confidence level) confirmed that big trees in the Kenaboi FR rehabilitated area had originated from genetically diverse seed trees of the Sungai Menyala Forest Reserve which were used as the planting stock for the taungya restoration system. Maternal contribution showed that the allele contribution of the small trees came from the planted S. acuminata trees within the study area. The high genetic diversity of small trees in this study provides strong evidence that the existing big trees would be suitable for a genetically diverse seed collection to rehabilitate other degraded forests. Sustainable forest management must emphasise genetic diversity in order to ensure the resilience of rehabilitated forest ecosystems.

Assessment on the Suitability of Planting Non-Native Peatlands Species Falcataria moluccana (Miq.) Barneby & Grimes in Rewetted Peatlands

Sengon (Falcataria moluccana), a fast-growing timber tree that naturally grows on mineral soils, is currently promoted in peatlands. This study aimed to (1) experimentally test the response of sengon seedlings in waterlogged conditions in the nursery; (2) describe and analyze the biophysical condition of a sengon plantation and its growth; (3) describe sengon farm practices on peatlands; and (4) identify key actor’s perception on planting sengon on peatlands. This study combined an experiment in nursery, field measurements, and key-informant interviews. The nursery experiment showed that peat soil affected seedling’s growth: survival rates decreased by 25–33% after 3 months of inundation. Sengon growth at age 1–5-years-old in peat soil was slower than that on mineral soils. Sengon growth in peatland was influenced by peat depth and peat maturity. Sengon plantation in Central Kalimantan was driven by market availability and industrial wood demand. Fourty-three percent of respondents thought sengon does not grow well in peat soils, but 57% of respondents thought that additional soil treatment will enhance site suitability. Based on key-informants’ experience, 64% disagree with sengon development in peatlands. Our study provides evidence that sengon is predominantly not suitable to be planted on peatlands. Therefore, cautions need to be taken when planting sengon on peatland areas.

ANALYSIS OF THE STATE OF PLANT COMMUNITIES IN THE DOLINSKY NATURE SANCTUARY (SAKHALIN) ACCORDING TO SATELLITE SURVEYS

The determination ratio of timber tree in the composition of stands makes it possible to judge about geoecological state of the vegetation cover. It be noted heterogeneous studying of forests in different regions of the country, in connection with which the research of specially protected natural areas (SPNA), which includes the Dolinsky Nature Sanctuary, with an insufficient number of employees in the forest industry, becomes especially relevant. Automated decoding of remote sensing data serves as an aid to ground-based observations. Work to identify the species composition of forests according to aerospace surveys on the territory of Sakhalin Island previously carried out in small volumes. The Sentinel-2 satellite images of the territory of the Dolinsky Nature Sanctuary, obtained in 2018-2021, analyzed in order to identify the classification features of various plant communities characteristic of the southern part of Sakhalin. On basis of visual interpretation, reference sites for geobotanical studies were identified, which with a high degree of confidence attributed to specific plant formations: fir-spruce, stone-birch, willow-alder river valleys, bamboo, deforested areas and plantings of pine and larch crops. Further work carried out using the methods of geoinformation analysis in ArcGIS. The optimal combinations of channels in the formation of synthesized image composites for the selection of training samples for each plant formation were determined when performing vegetation classification. In case of difficulties with the separation of some formations (larch - pine) in the images, the work carried out based on the materials of multi-season surveys. The obtained characteristics of the training samples can be used for further research in the Dolinsky Nature Sanctuary and beyond.

Towards Silviculture Guidelines to Produce Large-Sized Silver Birch (Betula pendula Roth) Logs in Western Europe

Forest health problems arising from climate change, pests and pathogens are a threat to the main timber tree species. As a result, silver birch (Betula pendula Roth) has become a precious asset for meeting oncoming forestry challenges in western Europe. However, silviculture guidelines to produce high-value birch logs in this region are lacking. Producing large-sized birch trunks requires crown release, i.e., removing crown competitors around selected target trees. These interventions are currently seldom carried out or else too late when the growth potential of the trees has already diminished. This study set out to ascertain the diameter at breast height (dbh) that could be reached by crown-released birch, determine dbh-associated crown diameters, and further characterize the gain obtained from early crown release on birch dbh growth. We measured 704 birch trees that had undergone crown release in 38 naturally regenerated pure birch stands in southern Belgium and in northeastern France. We then evaluated the variation in stem and crown diameter, and analyzed increments in response to the earliness of the interventions in three subsamples, also compared with control target birch. We found that trees with a dbh of 50 cm could be grown within 60 years. Based on crown diameter, to produce 40, 50 and 60 cm dbh trunk, the distance required between target birch trees at the end of the rotation was around 8, 10 and 12 m. With no intervention and in ordinary dense birch regenerations, the dbh increment was found to decline once the stand reached age 4–7 years. Starting crown release in stands aged 4–5 years can double the dbh increment of target trees and provide a continual gain that may last up to 20 years. When birch crowns are released after 9–12 years, it may already be too late for them to recover their best growth rate. Our contribution should help complete emerging guidelines in support of birch silviculture development.