Rangewide ploidy variation and evolution in Acacia senegal: a north-south divide?

Knowledge of rangewide variation in DNA content and ploidy level may be valuable in understanding the evolutionary history of a species. Recent studies of Acacia senegal report diploids and occasional tetraploids in the Sudano-Sahelian region of sub-Saharan Africa, but nothing is known about the overall extent of DNA ploidy variation within the species. In this study, we determine the DNA content and ploidy level of A. senegal across its native range, and explore whether the variation is related to its evolutionary and colonization history. We used propidium iodide flow cytometry (FCM) to estimate DNA content (2C value) and infer ploidy in 157 individuals from 54 populations on various tissues, using seeds, fresh leaves, dried leaves and twigs and herbarium specimens. The mean 2C DNA (pg ± s.d.) contents detected were 1.47 ± 0.09, 2.12 ± 0.02, 2.89 ± 0.12, and a single individual with 4.51 pg, corresponding to a polyploid series of diploid, triploid, tetraploid and hexaploid individuals. Diploids were confirmed by chromosome counts (2n = 2x = 26). Most populations (90.7 %) were of single ploidy level, while mixed ploidy populations (9.3 %) comprising mostly diploids (2x+3x, 2x+4x and 2x+6x) were restricted to the Sudano-Sahelian and Indian subcontinent regions, its northern range. The species is predominantly diploid, and no mixed ploidy populations were detected in east and southern Africa, its southern range. The geographic pattern of ploidy variation in conjunction with existing phylogeographic and phylogenetic data of the species suggests that polyploids have occurred multiple times in its evolutionary and recent colonization history, including contemporary ecological timescales. The successful use of external tissues of dried twigs in FCM is new, and presents the opportunity to study numerous other dryland woody species

Effect of indigenous and introduced arbuscular mycorrhizal fungi on growth and phytochemical content of vegetatively propagated Prunus africana (Hook. f.) Kalkman provenances

Prunus africana bark contains phytochemical compounds used in the treatment of benign prostatic hyperplasia and prostate cancer. It has been shown that this plant establishes association with arbuscular mycorrhizal fungi (AMF). AMF are involved in nutrient uptake, which may also affect plant growth and secondary metabolites composition. However, there is no information regarding the role of AMF in the growth and phytochemical content of P. africana. A pot experiment was carried out to assess the response of 8 months old vegetatively propagated P. africana seedlings inoculated with indigenous AMF collected from Mount Cameroon (MC) and Mount Manengumba (MM) in Cameroon, Malava near Kakamega (MK) and Chuka Tharaka-Nithi (CT) in Kenya. Mycorrhizal (frequency, abundance and intensity), growth (height, shoot weight, total weight, number of leaf, leaf surface) and phytochemical (total phenol, tannin and flavonoids) parameters were measured three months after growth of seedlings from two provenances (Muguga and Chuka) with the following inoculation treatments: MK, CT, MC, MM, non-sterilized soil (NS) and sterilized sand as non-inoculated control. Results showed that seedling heights were significantly increased by inoculation and associated with high root colonization (>80%) compared to non-inoculated seedlings. We also found that AMF promoted leaf formation, whereas inoculation did not have any effect on the seedling total weight. AMF inoculum from MM had a higher tannin content, while no significant difference was observed on the total phenol and flavonoid contents due to AMF inoculation. Pearson’s correlation was positive between mycorrhizal parameters and the growth parameters, and negative with phytochemical parameters. This study is the first report on the effect of AMF on the growth and phytochemical in P. africana. Further investigations are necessary to determine the effect of single AMF strains to provide better understanding of the role of AMF on the growth performance and physiology of this important medicinal plant species

Senegalia Senegal response to inoculation with rhizobial strains vary in relation to seed provenance and soil type

Aims: The focus of the study was to determine the symbiotic and growth response of three Senegalia Senegal (Syn. Acacia Senegal, gum arabic tree) provenances, namely Dahra (Senegal), Tera (Niger) and Makueni (Kenya) to inoculation with selected S. Senegal-nodulating rhizobia in soils from Dahra and Goudiry regions of Senegal, representing typical soil and enviromental conditions for establishing gum arabic production plantations. Methods: A greenhouse experiment was performed to evaluate the effect of 11 rhizobial strains on nodulation and growth of three S. Senegal provenances in two field soils, differing in nutrient status and indigenous rhizobia. After 4 months, plants were harvested for determination of nodulation, shoot and root dryweight. Results: Nodulation and growth of S. Senegal varied in relation to rhizobial strain, provenance, soil type, and their interactions. Generally, nodulation was higher in Dahra than Goudiry soils, while Makueni provenance was the most compatible host. Inoculation had a significant effect on all parameters measured in Dahra field soil. By contrast, inoculation had a significant effect on height (shoot length), and shoot, root and total dry matter but not on nodulation. In the two field soils, seed provenance effect was significant for all parameters measured. The interaction between inoculation and provenance showed a significant effect on all parameters measured except nodule number in Dahra field soil while in Goudiry, the interaction had a significant effect on seedling height and shoot, root, and total dry matter but this effect was not significant with nodulation parameters. Conclusions: S. Senegal is variable in its response to inoculation, it is therefore advantageous to select and match effective rhizobia-provenance symbionts for each site

Leaf Protein and Mineral Concentrations across the “Miracle Tree” Genus Moringa

The moringa tree Moringa oleifera is a fast-growing, drought-resistant tree cultivated across the lowland dry tropics worldwide for its nutritious leaves. Despite its nutritious reputation, there has been no systematic survey of the variation in leaf nutritional quality across M. oleifera grown worldwide, or of the other species of the genus. To guide informed use of moringa, we surveyed protein, macro-, and micro- nutrients across 67 common garden samples of 12 Moringa taxa, including 23 samples of M. oleifera. Moringa oleifera, M. concanensis, M. stenopetala, an M. concanensis X oleifera hybrid, and M. longituba were highest in protein, with M. ruspoliana having the highest calcium levels. A protein-dry leaf mass tradeoff may preclude certain breeding possibilities, e.g. maximally high protein with large leaflets. These findings identify clear priorities and limitations for improved moringa varieties with traits such as high protein, calcium, or ease of preparation

Knowledge needs for the operationalisation of the concept of ecosystem services

As environmental challenges and their management are increasingly recognised as complex and uncertain, the concept of ecosystem services has emerged from within scientific communities and is gaining influence within policy communities. To better understand how this concept can be turned into practice we examine knowledge needs from the perspective of the different stakeholders directly engaged with the operationalisation of ecosystem systems concept within ten socio-ecologically different case studies from different countries, levels of governance and ecosystems.We identify four different but interrelated areas of knowledge needs, namely; (i) needs related to develop a common understanding, (ii) needs related to the role of formal and informal institutions in shaping action on the ground, (iii) needs related to linking knowledge and action, and (iv) and needs related to accessible and easy to use methods and tools. These findings highlight the need to view knowledge as a process which is orientated towards action. We discuss the potential to develop transdisciplinary research approaches and the development of tools and methods explicitly as boundary objects in the ecosystem service science community to develop more collaborative practices with other stakeholders and facilitate the operationalisation of the concept of ecosystem services across contexts

(Dis) integrated valuation - Assessing the information gaps in ecosystem service appraisals for governance support

The operational challenges of integrated ecosystem service (ES) appraisals are determined by study purpose, system complexity and uncertainty, decision-makers' requirements for reliability and accuracy of methods, and approaches to stakeholder-science interaction in different decision contexts. To explore these factors we defined an information gap hypothesis, based on a theory of cumulative uncertainty in ES appraisals. When decision context requirements for accuracy and reliability increase, and the expected uncertainty of the ES appraisal methods also increases, the likelihood of methods being used is expected to drop, creating a potential information gap in governance. In order to test this information gap hypothesis, we evaluate 26 case studies and 80 ecosystem services appraisals in a large integrated EU research project. We find some support for a decreasing likelihood of ES appraisal methods coinciding with increasing accuracy and reliability requirements of the decision-support context, and with increasing uncertainty. We do not find that information costs are the explanation for this information gap, but rather that the research project interacted mostly with stakeholders outside the most decision-relevant contexts. The paper discusses how alternative definitions of integrated valuation can lead to different interpretations of decision-support information, and different governance approaches to dealing with uncertainty. (C) 2017 Elsevier B.V. All rights reserved.Peer reviewe

Integrating methods for ecosystem service assessment: Experiences from real world situations

The Ecosystem Services (ES) concept highlights the varied contributions the environment provides to humans and there are a wide range of methods/tools available to assess ES. However, in real-world decision contexts a single tool is rarely sufficient and methods must be combined to meet practitioner needs. Here, results from the OpenNESS project are presented to illustrate the methods selected to meet the needs of 24 real-world case studies and better understand why and how methods are combined to meet practical needs. Results showed that within the cases methods were combined to: i) address a range of ES; ii) assess both supply and demand of ES; iii) assess a range of value types; iv) reach different stake-holder groups v) cover weaknesses in other methods used and vi) to meet specific decision context needs. Methods were linked in a variety of ways: i) as input-output chains of methods; ii) through learning; iii) through method development and iv) through comparison/triangulation of results. The paper synthesises these case study-based experiences to provide insight to others working in practical contexts as to where, and in what contexts, different methods can be combined and how this can add value to case study analyses. (C) 2017 Published by Elsevier B.V.Peer reviewe

Integrated assessment and valuation of ecosystem services - Guidelines and experiences

EU FP7 OpenNESS project deliverable D33 & D4

tropiTree:an NGS-based EST-SSR resource for 24 tropical tree species

The development of genetic tools for non-model organisms has been hampered by cost, but advances in next-generation sequencing (NGS) have created new opportunities. In ecological research, this raises the prospect for developing molecular markers to simultaneously study important genetic processes such as gene flow in multiple non-model plant species within complex natural and anthropogenic landscapes. Here, we report the use of bar-coded multiplexed paired-end Illumina NGS for the de novo development of expressed sequence tag-derived simple sequence repeat (EST-SSR) markers at low cost for a range of 24 tree species. Each chosen tree species is important in complex tropical agroforestry systems where little is currently known about many genetic processes. An average of more than 5,000 EST-SSRs was identified for each of the 24 sequenced species, whereas prior to analysis 20 of the species had fewer than 100 nucleotide sequence citations. To make results available to potential users in a suitable format, we have developed an open-access, interactive online database, tropiTree (http://bioinf.hutton.ac.uk/tropiTree), which has a range of visualisation and search facilities, and which is a model for the efficient presentation and application of NGS data