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The agarwood-producing genera, Aquilaria and Gyrinops , have been treated as sister genera in Thymelaeaceae (Aquilarieae, Malvales). However, there are differing opinions about their taxonomic positions. Using new evidence from complete plastid genome (plastome) sequences of 12 Aquilaria spp. and seven Gyrinops spp. corresponding to more than half the total number of species recognized in each genus, we reconstructed a phylogenetic tree of Aquilarieae. Members of both genera shared similar sequence variations at the plastome level. The phylogenetic relationships of the two genera were completely resolved using the complete plastome sequences. Gyrinops was paraphyletic to Aquilaria , i.e. Aquilaria nested in Gyrinops. Overlapping clustering patterns were observed from topology-clustering analysis using the complete plastome and the protein-coding gene sequences, which further reinforced the paraphyletic link. The maximum-likelihood-based RelTime analysis suggested that Aquilarieae and Daphneae diverged c. 44 Mya during the Eocene, followed by a rapid divergence event in Aquilarieae, with the split between G. vidalii and G. walla c. 1.24 Mya during the Pleistocene. Our new phylogenetic estimation demonstrates the relationship between the two genera, which will aid in future taxonomic revisions involving members of Aquilarieae. [ABSTRACT FROM AUTHOR]

Endophytic fungi (EPF) colonize plant roots and enhance their growth. The relationship between host plant and EPF can be affected by several factors, such as growth media, host species, and fungal species. The objective of this study was to clarify the effect of nutrient concentration in growth media on the relationship between host plant and root EPF. Brassica campestris was grown in 1/100 Murashige and Skoog (MS), 1/10 MS, 1/100 MS and 1/10 nitrogen (high N), and 1/100 MS and 1/10 phosphorus (high P) media. B. campestris was inoculated with four root EPFs isolated from forest soils in Indonesia and harvested 28 days after transplant. Shoot dry weight (SDW) and colonization in roots were measured. All the isolates colonized roots of B. campestris. Two isolates increased the SDW of B. campestris grown on 1/100 MS media. The shoot growth response of B. campestris to EPF colonization on 1/100 MS was higher than that on 1/100 high N and 1/100 high P MS media. These results suggest that concentration of nitrogen and phosphorus in growth media determine the relationship between B. campestris and root EPF. [ABSTRACT FROM AUTHOR]

In Southeast Asia, primary tropical rainforests are usually dominated by ectomycorrhizal (ECM) trees belonging to Dipterocarpaceae, although arbuscular mycorrhizal trees often outcompete them after disturbances such as forest fires and clear-cutting, thus preventing dipterocarp regeneration. In some secondary tropical forests, however, potentially ECM trees belonging to Tristaniopsis (Myrtaceae) become dominant and may help ECM dipterocarp forests to recover. However, we have no information about their mycorrhizal status in these settings. In this study, we analyzed ECM fungal communities in tropical secondary forests dominated by Tristaniopsis and investigated which ECM fungal species are shared with other tropical or temperate areas. In total, 100 samples were collected from four secondary forests dominated by Tristaniopsis on Bangka Island. ECM tips in the soil samples were subjected to molecular analyses to identify both ECM and host species. Based on a >97% ITS sequence similarity threshold, we identified 56 ECM fungal species dominated by Thelephoraceae, Russulaceae, and Clavulinaceae. Some of the ECM fungal species were shared between dominant Tristaniopsis and coexisting Eucalyptus or Quercus trees, including 5 common to ECM fungi recorded in a primary mixed dipterocarp forest at Lambir Hill, Malaysia. In contrast, no ECM fungal species were shared with other geographical regions, even with Tristaniopsis in New Caledonia. These results imply that secondary tropical forests dominated by Tristaniopsis harbor diverse ECM fungi, including those that inhabit primary dipterocarp forests in the same geographical region. They may function as refugia for ECM fungi, given that dipterocarp forests are disappearing quickly due to human activity. [ABSTRACT FROM AUTHOR]

Indonesia is home to several tree taxa that are harvested for agarwood. This highly valuable oleoresin ironically was the cause for some species to become vulnerable due to gluttonous human activity. However, information on the genetic diversity of these endangered trees is limited. In this study, 28 specimens representing eight species from two genera, Aquilaria and Gyrinops, were collected from ex-situ and in-situ populations in Indonesia. Phylogenetic analysis conducted on DNA sequences of the nuclear ribosomal internal transcribed spacer (ITS) and the trnL-trnF intergenic spacer regions, revealed that Aquilaria and Gyrinops are paraphyletic when Aquilaria cumingiana is excluded. The phylogenetic analysis for ITS and trnL-trnF showed capability to categorise agarwoodproducing species based on their regions: East Indonesia and West Indonesia, using Wallace's Line as the divider. In addition, we discuss challenges in species identification and taxonomy of agarwood-producing genera, and their conservation efforts in Indonesia. [ABSTRACT FROM AUTHOR]

The effect of arbuscular mycorrhizal (AM) colonization on nitrogen (N) and phosphorus (P) uptake and shoot growth of Aloe vera was investigated. Plants were inoculated with one of two AM fungi, Glomus clarum or Gigaspora decipiens. Control plants were not inoculated. Plants were grown under glasshouse conditions in a peat land soil without fertilizers for 12 months. Inoculated A. vera plants were colonized with AM fungi. Total length of leaves and number of leaves were higher in inoculated plants than uninoculated plants 12 months after inoculation. Shoot N and P concentrations were higher in inoculated plants than uninoculated plants. Shoot fresh weight was increased by AM colonization. This result suggests that AM colonization can increase the nutrient uptake and growth of A. vera. [ABSTRACT FROM AUTHOR]

Gaharu or agarwood or oudh is a fragrant and highly valuable nontimber forest product obtained from several species of trees that produce it in response to wounding or fungal attack. The aims of the study were to evaluate the sound wave velocity change from green to dry conditions in agarwood and tomographic images associated with changes in the moisture content. A total of 10 trees were selected for this study; five trees were artificially inoculated and the other five were left untreated. After in situ measurement of standing trees stem using nondestructive testing (PiCUS sonic tomography), air-dried disk samples from the trees were assessed. The results showed that sonic velocity values increase from 12% to 22% as moisture content decreases from a green condition (live tree) to an air-dried condition (disk sample). Nevertheless, solid and damage areas revealed only slight differences on the tomograms. This research combines traditional visual assessment with tomography to better detect the presence of agarwood in trees. [ABSTRACT FROM AUTHOR]

The article discusses the collaboration between the Center for Standardization of Disaster Resilience and Climate Change Instruments, Indonesia Ministry of Environment and Forestry, and the Mushroom Initiative to restore degraded peatlands in Indonesia using the 4N rehabilitation concept. The 4N approach involves avoiding the use of plastic, burning, and chemical fertilizers, and promoting native peatland tree species. The project successfully rehabilitated 116 hectares of tropical peatlands, planting over 190,000 seedlings of native peatland species. The 4N approach has multiple benefits, including reducing greenhouse gas emissions and promoting sustainability and community involvement. [Extracted from the article]