Facts and challenges in the understanding of the biosynthesis of peptaibols by Trichoderma

Species of the mitosporic filamentous fungal genus Trichoderma are prominent producers of both short (7-11 residues) and long (18-20 residues) peptaibols and peptaibiotics, which are thought to be involved in their interaction with other living systems. Numerous reviews are available regarding biodiversity, structure, and mode of action of these peptide derivatives, but little emphasis has been paid to the physiology and genetics of their formation. In this review article, we used the recent knowledge on biosynthesis and production of these components to speculate on some of the unknown points. We also highlight areas where further research is most urgently needed.     

Rare medicinal herbs of the Himalayas: an ardent need for preservation

The forest wealth of the Himalayan ranges is abundant with unique medicinal herbs, having tremendous economic importance. Latterly, these have adversely suffered at the hands of poachers and unlawful trade activities. The author cites the names of some of the rare species, in a bid to achieve their conservation through sensitization and participation of the masses, especially the tribals, in the greater interest of humanity.     

土著知识在生物多样性保护和利用中的研究进展

土著知识作为一种特定的知识形态,在保护生物多样性、促进资源可持续利用和社会协调发展等方面具有重要的作用,越来越受到社会各界尤其是学术界的重视。为了让大家更好地了解土著知识研究的状况,结合我们开展的工作,从国内外土著知识研究简史、土著知识研究代表性项目和单位及资助机构、土著知识项目实施产生的效果、土著知识研究利用的展望4个方面进行了综述。     

自然保护地生物多样性保护研究进展

建立自然保护地是保护生物多样性最为重要的措施之一。总体来看, 自然保护地生物多样性保护研究主要围绕关键生态系统以及珍稀濒危物种等保护对象的状态以及变化两个层面进行, 并重点关注自然保护地数量与面积、保护了多少重要生态系统和物种、能否有效保护生物多样性等一系列科学问题。然而, 在自然保护地生物多样性保护研究方面, 还缺少针对上述研究领域的系统性综述。为此, 本文系统梳理了自然保护地空间布局及其与生物多样性分布的关系、自然保护地生物多样性变化及其保护成效等近20年来相关领域的研究进展。自然保护地的空间布局以及与生物多样性分布的关系主要围绕自然保护地与生物多样性在某一阶段的状态开展研究, 致力于探究自然保护地“保护多少” “代表性如何” “在哪儿保护”等一系列关键科学问题。同时, 自然保护地内的生物多样性会随着气候变化、人类活动以及自身演替等发生时空动态变化, 基于自然保护地生物多样性变化分析, 各国学者在全球尺度、国家尺度和单个自然保护地进行了大量的保护成效评估研究, 并逐渐发展出了自然保护地内外配对分析方法以提升保护成效评估的精度, 进而识别出不同自然保护地的主要影响因素。在此基础上, 本文进一步对自然保护地生物多样性保护研究提出了展望, 主要包括: (1)综合考虑自然保护地生物多样性状态和变化; (2)开展多目标协同的自然保护地空间优化布局; (3)强化自然保护地主要保护对象的识别、调查与监测; (4)提升自然保护地的质量和连通性; (5)探究自然保护地管理措施与保护成效的关联机制。本文可为“2020年后全球生物多样性框架”的制定与实施特别是在自然保护地体系建设与优化方面提供参考与借鉴。     

中国生物多样性核心监测指标遥感产品体系构建与思考

生物多样性的稳定维持关乎人类生存发展与地球健康。生物多样性核心监测指标(Essential Biodiversity Variables, EBVs)旨在结合地面调查与遥感技术, 为大尺度、长时间序列的生物多样性监测提供新的解决方案。然而, 目前学界仍然缺乏一套国家尺度标准化EBVs遥感监测产品数据集, 以进行生物多样性评估。本研究旨在对中国生物多样性核心监测指标遥感产品进行体系构建与思考, 首先综述了目前EBVs的遥感研究概况, 并根据EBVs研究文献的数量进行调研分析; 同时, 本文在已有遥感生物多样性产品优先标准的基础上, 添加了“可重复性”的新标准, 并据此构建了中国EBVs遥感产品体系与监测数据集的指标清单, 最终对中国EBVs遥感研究存在的问题进行思考与讨论。本研究可为中国的生物多样性遥感监测提供科学依据, 有望为中国生物多样性政策的制定提供支撑。     

Insect trypanosomatids in Papua New Guinea: high endemism and diversity

The extreme biological diversity of Oceanian archipelagos has long stimulated research in ecology and evolution. However, parasitic protists in this geographic area remained neglected and no molecular analyses have been carried out to understand the evolutionary patterns and relationships with their hosts. Papua New Guinea (PNG) is a biodiversity hotspot containing over 5% of the world's biodiversity in less than 0.5% of the total land area. In the current work, we examined insect heteropteran hosts collected in PNG for the presence of trypanosomatid parasites. The diversity of insect flagellates was analysed, to our knowledge for the first time, east of Wallace's Line, one of the most distinct biogeographic boundaries of the world. Out of 907 investigated specimens from 138 species and 23 families of the true bugs collected in eight localities, 135 (15%) were infected by at least one trypanosomatid species. High species diversity of captured hosts correlated with high diversity of detected trypanosomatids. Of 46 trypanosomatid Typing Units documented in PNG, only eight were known from other geographic locations, while 38 TUs (~83%) have not been previously encountered. The widespread trypanosomatid TUs were found in both widely distributed and endemic/sub-endemic insects. Approximately one-third of the endemic trypanosomatid TUs were found in widely distributed hosts, while the remaining species were confined to endemic and sub-endemic insects. The TUs from PNG form clades with conspicuous host-parasite coevolutionary patterns, as well as those with a remarkable lack of this trait. In addition, our analysis revealed new members of the subfamilies Leishmaniinae and Strigomonadinae, potentially representing new genera of trypanosomatids.     

Effect of Environmental Factors on Cyanobacteria Richness in Some Agricultural Soils

The physicochemical variations of soil, such as temperature, pH, nutrients, and the type of plant cultivation, affect the diversity of cyanobacteria, whether heterocystous or not. The aim of this study was to identify the species of cyanobacteria in a soil and the effect of environmental characteristics on cyanobacteria. Soil samples collected from six different agricultural sites in Al Diwaniyah city/Iraq during September 2016 in the autumn season were analyzed, and the physicochemical characteristics of the samples were measured using approved methods.

The results showed significant correlation and differences between cyanobacteria composition, distribution, and physicochemical factors among soil sites. The Agricultural soil was slightly alkaline and moderately saline and contained abundant nutrients, cations and a high percentage of organic matter. All these characteristics influenced the distribution and diversity of cyanobacteria. Ninety-six species were identified, including four heterocystous species represented by Anabaena, Calothrix, Cylnidrospermum, and Nostoc. However, the non-heterocystous were represented by 13 species: Aphanocapsa, Aphanothece, Arthrospira, Chroococcus, Gloeocapsa, Lyngbya, Merismopedia, Microcystis, Microcoleus, Oscillatoria, Phormidium, Schizothrix, and Spirulina. The dominant species of cyanobacteria was Oscillatoria, followed by Phormidium, Chroococcus, Gleocapsa and Lyngbya. The highest value of Shannon’s and Simpson’s diversities were registered in the Ghammas site, which is a paddy field, but the lowest was registered in the Afak site, cultivated with the alfalfa plant. Soil was classified as finely textured with silty clayey characterization, favorable for cyanobacteria growth.     

Non‐verbal mate retention behaviour in women and its relation to couple's relationship adjustment and satisfaction

The function of mate retention strategies is to preserve the bond between romantic partners and to prevent desertion, which is also why such behaviours are often elicited by the presence of a potential rival. Most existing studies on mate retention are based on self‐reports, which are prone to various biases. In this study, we observed non‐verbal behaviour of 47 long‐term romantic heterosexual couples during their interview with a female experimenter, whom the women in the couples may have perceived as a potential rival. We measured non‐verbal displays of mate retention tactics (direct guarding, intimacy inducement, appearance enhancement, and love and care display), as well as relationship maintenance strategies of openness and positivity. We expected that relationship quality as reported by both partners in the couple would be positively associated with ‘benefit‐provisioning’ mate retention behaviours and negatively associated with a ‘cost‐inflicting’ mate retention tactic (direct guarding). Relationship quality was assessed by Spanier's Dyadic Adjustment Scale using both the total score of dyadic adjustment and a Dyadic Satisfaction subscale. We found a significant association between both partners' dyadic adjustment and satisfaction and woman's appearance enhancement behaviours (such as self‐touch, hair flip and primp) in the presence of her partner and a potential rival. We also found a negative association between partner's dyadic adjustment and woman's direct guarding of partner using short looks, and a positive association between woman's intimacy‐inducing behaviour using long gaze and her own dyadic satisfaction and her partner's dyadic adjustment. Our results highlight the specific role of female attractiveness in later stages of romantic relationships within the context of mate retention and draw attention to the significance of the use of observational techniques in addition to self‐reports.     

A comparison between the homocyclic aromatic metabolic pathways from plant-derived compounds by bacteria and fungi

Aromatic compounds derived from lignin are of great interest for renewable biotechnical applications. They can serve in many industries e.g. as biochemical building blocks for bioplastics or biofuels, or as antioxidants, flavor agents or food preservatives. In nature, lignin is degraded by microorganisms, which results in the release of homocyclic aromatic compounds. Homocyclic aromatic compounds can also be linked to polysaccharides, tannins and even found freely in plant biomass. As these compounds are often toxic to microbes already at low concentrations, they need to be degraded or converted to less toxic forms. Prior to ring cleavage, the plant- and lignin-derived aromatic compounds are converted to seven central ring-fission intermediates, i.e. catechol, protocatechuic acid, hydroxyquinol, hydroquinone, gentisic acid, gallic acid and pyrogallol through complex aromatic metabolic pathways and used as energy source in the tricarboxylic acid cycle. Over the decades, bacterial aromatic metabolism has been described in great detail. However, the studies on fungal aromatic pathways are scattered over different pathways and species, complicating a comprehensive view of fungal aromatic metabolism. In this review, we depicted the similarities and differences of the reported aromatic metabolic pathways in fungi and bacteria. Although both microorganisms share the main conversion routes, many alternative pathways are observed in fungi. Understanding the microbial aromatic metabolic pathways could lead to metabolic engineering for strain improvement and promote valorization of lignin and related aromatic compounds.     

Ensifer fredii symbiovar vachelliae nodulates endemic Vachellia gummifera in semiarid Moroccan areas

The purpose of this work was to study the genetic diversity of the nodule-forming bacteria associated with native populations of Vachellia gummifera growing wild in Morocco. The nearly complete 16S rRNA gene sequences from three selected strains, following ARDRA and REP-PCR results, revealed they were members of the genus Ensifer and the sequencing of the housekeeping genes recA, gyrB, dnaK and rpoB, and their concatenated phylogenetic analysis, showed that the 3 strains belong to the species E. fredii. Based on the nodC and nodA phylogenies, the 3 strains clearly diverged from the type and other reference strains of E. fredii and formed a clearly separated cluster. The strains AGA1, AGA2 and AGB23 did not form nodules on Glycine max, Phaseolus vulgaris and Medicago truncatula, and effectively nodulated V. gummifera, Acacia cyanophylla, Prosopis chilensis and Leucaena leucocephala. Based on similarities of the nodC and nodA symbiotic genes and differences in the host range, the strains isolated from Moroccan endemic V. gummifera may form a different symbiovar within Ensifer species, for which the name “vachelliae” is proposed.