CCAFS Deep Dive Assessment of Climate-Smart Agriculture (CSA) in the Feed the Future Portfolio in Senegal

As part of a global effort that will inform how Feed the Future tracks CSA across the 19 focus countries (plus aligned) the CCAFS and USAID/BFS team selected 5 to carry out a deeper analysis of their portfolio. In July 2015, CCAFS’ visit to the USAID Senegal mission provided an opportunity to identify and discuss CSA-related activities within the country and the USAID zone of influence (ZOI) highlighting the importance of addressing the effects of climate change in the agricultural sector and the current and potential benefits of Feed the Future’s presence for climate resilience. The visit included meetings with USAID Mission staff, Feed the Future implementing partners, and three government agencies. The process also included the review of Feed the Future strategy and project documents, as well as a limited external literature review. This report outlines the key findings of the visit and highlights some ways in which CSA approaches can be further incorporated into the Mission’s future programming

Stem, root, and older leaf N:P ratios are more responsive indicators of soil nutrient availability than new foliage

Author Posting. © Ecological Society of America, 2014. This article is posted here by permission of Ecological Society of America for personal use, not for redistribution. The definitive version was published in Ecology 95 (2014): 2062–2068, doi:10.1890/13-1671.1.Foliar nitrogen to phosphorus (N:P) ratios are widely used to indicate soil nutrient availability and limitation, but the foliar ratios of woody plants have proven more complicated to interpret than ratios from whole biomass of herbaceous species. This may be related to tissues in woody species acting as nutrient reservoirs during active growth, allowing maintenance of optimal N:P ratios in recently produced, fully expanded leaves (i.e., “new” leaves, the most commonly sampled tissue). Here we address the hypothesis that N:P ratios of newly expanded leaves are less sensitive indicators of soil nutrient availability than are other tissue types in woody plants. Seedlings of five naturally established tree species were harvested from plots receiving two years of fertilizer treatments in a lowland tropical forest in the Republic of Panama. Nutrient concentrations were determined in new leaves, old leaves, stems, and roots. For stems and roots, N:P ratios increased after N addition and decreased after P addition, and trends were consistent across all five species. Older leaves also showed strong responses to N and P addition, and trends were consistent for four of five species. In comparison, overall N:P ratio responses in new leaves were more variable across species. These results indicate that the N:P ratios of stems, roots, and older leaves are more responsive indicators of soil nutrient availability than are those of new leaves. Testing the generality of this result could improve the use of tissue nutrient ratios as indices of soil nutrient availability in woody plants.Data are from Santiago et al. (2012), which was supported by a grant from the Andrew W. Mellon Foundation to S. J. Wright, a Smithsonian Institute Scholarly Studies grant to S. J. Wright and J. B. Yavitt, and a University of California Regent’s Faculty Fellowship to L. S. Santiago. L. A. Schreeg was partially supported through a Marine Biological Laboratory-Brown University SEED grant to Z. Cardon, S. Porder, and L. A. Schreeg

A new piroplasmid species infecting dogs: Morphological and molecular characterization and pathogeny of Babesia negevi n. sp.

Introduction: Babesiosis is a protozoan tick-borne infection associated with anemia and life-threatening disease in humans, domestic and wildlife animals. Dogs are infected by at least six well-characterized Babesia spp. that cause clinical disease. Infection with a piroplasmid species was detected by light microscopy of stained blood smears from five sick dogs from Israel and prompted an investigation on the parasite's identity. Methods: Genetic characterization of the piroplasmid was performed by PCR amplification of the 18S rRNA and the cytochrome c oxidase subunit 1 (cox1) genes, DNA sequencing and phylogenetic analysis. Four of the dogs were co-infected with Borrelia persica (Dschunkowsky, 1913), a relapsing fever spirochete transmitted by the argasid tick Ornithodoros tholozani Laboulbène & Mégnin. Co-infection of dogs with B. persica raised the possibility of transmission by O. tholozani and therefore, a piroplasmid PCR survey of ticks from this species was performed. Results: The infected dogs presented with fever (4/5), anemia, thrombocytopenia (4/5) and icterus (3/5). Comparison of the 18S rRNA and cox1 piroplasmid gene sequences revealed 99-100% identity between sequences amplified from different dogs and ticks. Phylogenetic trees demonstrated a previously undescribed species of Babesia belonging to the western group of Babesia (sensu lato) and closely related to the human pathogen Babesia duncani Conrad, Kjemtrup, Carreno, Thomford, Wainwright, Eberhard, Quick, Telfrom & Herwalt, 2006 while more moderately related to Babesia conradae Kjemtrup, Wainwright, Miller, Penzhorn & Carreno, 2006 which infects dogs. The piroplasm forms detected included tetrads (Maltese cross), merozoite and trophozoite stages whose average size was larger than stages of other canine Babesia spp. belonging to the Babesia (s.l.) and B. gibsoni Patton, 1910, and smaller than other canine Babesia (sensu stricto) spp. Of 212 O. tholozani ticks surveyed, 11 (5.2%) harbored DNA of the new species of Babesia. Conclusions: Babesia negevi n. sp. is described based on morphological and genetic characterization and phylogenetic analyses. The species is named after the Negev desert of southern Israel, where the first infected dog originated from. Despite co-infection in four dogs, the fifth dog had fatal disease attesting that B. negevi n. sp. infection requires clinical attention. Incriminating O. tholozani or another tick species as the vector of Babesia negevi n. sp., would require additional studies.Fil: Baneth, Gad. The Hebrew University of Jerusalem; IsraelFil: Nachum Biala, Yaarit. Koret School Of Veterinary Medicine; IsraelFil: Birkenheuer, Adam Joseph. North Carolina State University; Estados UnidosFil: Schreeg, Megan Elizabeth. North Carolina State University; Estados UnidosFil: Prince, Hagar. North Carolina State University; Estados UnidosFil: Jacobsen, Monica Ofelia. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; ArgentinaFil: Schnittger, Leonhard. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; ArgentinaFil: Aroch, Itamar. Koret School Of Veterinary Medicine; Israe

Assessing Nutrient Limitation in Complex Forested Ecosystems : Alternatives to Large-Scale Fertilization Experiments

Quantifying nutrient limitation of primary productivity is a fundamental task of terrestrial ecosystem ecology, but in a high carbon dioxide environment it is even more critical that we understand potential nutrient constraints on plant growth. Ecologists often manipulate nutrients with fertilizer to assess nutrient limitation, yet for a variety of reasons, nutrient fertilization experiments are either impractical or incapable of resolving ecosystem responses to some global changes. The challenges of conducting large, in situ fertilization experiments are magnified in forests, especially the high-diversity forests common throughout the lowland tropics. A number of methods, including fertilization experiments, could be seen as tools in a toolbox that ecologists may use to attempt to assess nutrient limitation, but there has been no compilation or synthetic discussion of those methods in the literature. Here, we group these methods into one of three categories (indicators of soil nutrient supply, organismal indicators of nutrient limitation, and lab-based experiments and nutrient depletions), and discuss some of the strengths and limitations of each. Next, using a case study, we compare nutrient limitation assessed using these methods to results obtained using large-scale fertilizations across the Hawaiian Archipelago. We then explore the application of these methods in high-diversity tropical forests. In the end, we suggest that, although no single method is likely to predict nutrient limitation in all ecosystems and at all scales, by simultaneously utilizing a number of the methods we describe, investigators may begin to understand nutrient limitation in complex and diverse ecosystems such as tropical forests. In combination, these methods represent our best hope for understanding nutrient constraints on the global carbon cycle, especially in tropical forest ecosystems

Phylogenetic Beta Diversity Metrics, Trait Evolution and Inferring the Functional Beta Diversity of Communities

The beta diversity of communities along gradients has fascinated ecologists for decades. Traditionally such studies have focused on the species composition of communities, but researchers are becoming increasingly interested in analyzing the phylogenetic composition in the hope of achieving mechanistic insights into community structure. To date many metrics of phylogenetic beta diversity have been published, but few empirical studies have been published. Further inferences made from such phylogenetic studies critically rely on the pattern of trait evolution. The present work provides a study of the phylogenetic dissimilarity of 96 tree communities in India. The work compares and contrasts eight metrics of phylogenetic dissimilarity, considers the role of phylogenetic signal in trait data and shows that environmental distance rather than spatial distance is the best correlate of phylogenetic dissimilarity in the study system

Development of a DNA Barcoding System for Seagrasses: Successful but Not Simple

Seagrasses, a unique group of submerged flowering plants, profoundly influence the physical, chemical and biological environments of coastal waters through their high primary productivity and nutrient recycling ability. They provide habitat for aquatic life, alter water flow, stabilize the ground and mitigate the impact of nutrient pollution. at the coast region. Although on a global scale seagrasses represent less than 0.1% of the angiosperm taxa, the taxonomical ambiguity in delineating seagrass species is high. Thus, the taxonomy of several genera is unsolved. While seagrasses are capable of performing both, sexual and asexual reproduction, vegetative reproduction is common and sexual progenies are always short lived and epimeral in nature. This makes species differentiation often difficult, especially for non-taxonomists since the flower as a distinct morphological trait is missing. Our goal is to develop a DNA barcoding system assisting also non-taxonomists to identify regional seagrass species. The results will be corroborated by publicly available sequence data. The main focus is on the 14 described seagrass species of India, supplemented with seagrasses from temperate regions. According to the recommendations of the Consortium for the Barcoding of Life (CBOL) rbcL and matK were used in this study. After optimization of the DNA extraction method from preserved seagrass material, the respective sequences were amplified from all species analyzed. Tree- and character-based approaches demonstrate that the rbcL sequence fragment is capable of resolving up to family and genus level. Only matK sequences were reliable in resolving species and partially the ecotype level. Additionally, a plastidic gene spacer was included in the analysis to confirm the identification level. Although the analysis of these three loci solved several nodes, a few complexes remained unsolved, even when constructing a combined tree for all three loci. Our approaches contribute to the understanding of the morphological plasticity of seagrasses versus genetic differentiation

Potassium : a neglected nutrient in global change

L'article inclou sis apèndixsAim: Potassium (K) is the second most abundant nutrient after nitrogen (N) in plant photosynthetic tissues. Thousands of physiological and metabolic studies in recent decades have established the fundamental role of K in plant function, especially in water use efficiency and economy, and yet macroecological studies have mostly overlooked this nutrient.- Methods: We have reviewed available studies on the contents, stoichiometries and roles of potassium in the soil-plant system and in terrestrial ecosystems. We have also reviewed the impacts of global change drivers on K contents, stoichiometries, and roles. - Conclusions: The current literature indicates that K, at a global level, is as limiting as N and phosphorus (P) for plant productivity in terrestrial ecosystems. K limitation has been seen up to some degree in 70% of all studied terrestrial ecosystems. However, atmospheric K deposition from human activities represents higher amounts than that from natural sources in some areas. We are far from understanding the K fluxes between the atmosphere and land, and the role of anthropogenic activities in these fluxes. The increasing aridity expected in wide areas of the world makes K more critical through its role in water use efficiency. N deposition exerts a strong impact on the ecosystem K-cycle, decreasing K availability and increasing K limitation. Plant invasive success is enhanced by higher soil K availability, especially in environments without strong abiotic stresses. The impacts of other global change drivers, such as increasing atmospheric CO² or changes in land use remain to be elucidated. Current models of the responses of ecosystems and carbon storage to projected global climatic and atmospheric changes are now starting to consider N and P, but they should also consider K, mostly in arid and semiarid ecosystems