Moritz Mittelbach

Trade in Palm Products in North-Western South America

More than 200 scientific publications and Internet sources dealing with trade in palm products in north-western South America are reviewed. We focus on value chains, trade volumes, prices, and recent developments for some of the most important raw materials derived from native palms. Trade in palm products takes place at local, regional, national, and international levels. For local communities and individual households palm products may play a key role as the most important or only source of cash income. Most of these palm products are inadequately or not at all captured in trade statistics at the local and regional economic levels. Only products such as vegetable ivory and palm heart are monitored statistically, mainly because they are exported. Most raw materials derived from palms are extracted from the wild, and mainly by destructive harvesting. Reduced availability and rising prices on local and regional markets reflect incipient resource depletion. Only in vegetable ivory more or less sustainable wild harvesting methods prevail. Palm heart is increasingly being harvested from orchards and non-sustainable exploitation of wild populations is loosing ground. The international market for native palm oils and pulp (esp. Euterpe oleracea or açaí) is currently served almost exclusively from Brazil. Due to low oil contents and high production costs palm oils are currently used mainly for cosmetics. Based on their content of protein, starch, tocols, and carotenoids palm fruits have high nutritional value and represent a considerable potential for the development of functional foods, food supplements and animal fodder. Palms could undoubtedly play a more important role in the socio-economic development of north-western South America. Sustainability and marketing potential of palm products are negatively affected by the low income obtained by primary producers which often represents no more than 0.01–3% of the retail value. Poor governance, insecurity of land tenure and unequal sharing of profits endanger a sustainable long-term development of these valuable resources.ResumenSe revisan más de 200 publicaciones científicas y fuentes en Internet relacionadas con el comercio de productos de palmas en el noroeste de América del Sur. Nos enfocamos en las cadenas de valor, los volúmenes del comercio, los precios y el desarrollo reciente de algunas de las materias primas más importantes derivadas de las palmas. El comercio de productos de palmas se lleva a cabo a nivel local, regional, nacional e internacional. Para las comunidades locales y las familias individuales los productos de las palmas pueden desempeñar un papel clave como la fuente más importante o única de ingreso de dinero en efectivo, y esta importancia no se refleja adecuadamente en estadisticas oficiales. Los productos de las palmas se registran inadecuadamente en las estadísticas del comercio a nivel económico local y regional. Solamente los productos de palmas como el marfil vegetal y el meollo de palma son las que se monitorean estadísticamente debido principalmente a que son de exportación. La mayoría de las materias primas derivadas de las palmas se extraen de la naturaleza, principalmente por cosecha destructiva. La menor disponibilidad y el aumento de los precios en los mercados locales y regionales reflejan el agotamiento incipiente de los recursos. En el marfil vegetal prevalecen en mayor o menor medida técnicas de cosecha sostenible. Cada vez con mayor frecuencia el palmito se está cosechando de los huertos y la explotación no-sostenible de las poblaciones silvestres está perdiendo terreno. En la actualidad, el mercado internacional del aceite de palma nativa y la pulpa (especialmente Euterpe oleracea u açaí) está surtido casi exclusivamente por Brasil. Debido al contenido bajo de aceite y a los altos costos de producción, actualmente los aceites de palma se utilizan principalmente para cosméticos. Los frutos de las palmas tienen un alto valor nutricional (proteínas, almidón, tocols, carotenoides) y tienen un gran potencial para el desarrollo de alimentos funcionales, complementos alimenticios así como forraje para animales. Las palmas podrían desempeñar indudablemente un papel más importante en el desarrollo socio-económico del noroeste de América del Sur. La sostenibilidad y la comercialización potencial de los productos de las palmas son afectadas negativamente por los bajos ingresos obtenidos por los productores primarios de las materias primas (tipicamente 0.01 a 3% del precio de venta). La deficiente gestión gubernamental, la inseguridad de la tenencia de la tierra y la distribución desigual de los beneficios ponen en peligro el desarrollo sostentable a largo plazo de estos recursos valiosos.

Nectar sugars and bird visitation define a floral niche for basidiomycetous yeast on the Canary Islands.

BackgroundStudies on the diversity of yeasts in floral nectar were first carried out in the late 19th century. A narrow group of fermenting, osmophilous ascomycetes were regarded as exclusive specialists able to populate this unique and species poor environment. More recently, it became apparent that microorganisms might play an important role in the process of plant pollination. Despite the importance of these nectar dwelling yeasts, knowledge of the factors that drive their diversity and species composition is scarce.ResultsIn this study, we linked the frequencies of yeast species in floral nectars from various host plants on the Canary Islands to nectar traits and flower visitors. We estimated the structuring impact of pollination syndromes (nectar volume, sugar concentration and sugar composition) on yeast diversity.The observed total yeast diversity was consistent with former studies, however, the present survey yielded additional basidiomycetous yeasts in unexpectedly high numbers. Our results show these basidiomycetes are significantly associated with ornithophilous flowers. Specialized ascomycetes inhabit sucrose-dominant nectars, but are surprisingly rare in nectar dominated by monosaccharides.ConclusionsThere are two conclusions from this study: (i) a shift of floral visitors towards ornithophily alters the likelihood of yeast inoculation in flowers, and (ii) low concentrated hexose-dominant nectar promotes colonization of flowers by basidiomycetes. In the studied floral system, basidiomycete yeasts are acknowledged as regular members of nectar. This challenges the current understanding that nectar is an ecological niche solely occupied by ascomycetous yeasts.

Familial classification of the Boraginales

The Boraginales are now universally accepted as monophyletic and firmly placed in Lamiidae. However, a consensus about familial classification has remained elusive, with some advocating recognition of a single, widely variable family, and others proposing recognition of several distinct families. A consensus classification is proposed here, based on recent molecular phylogenetic studies, morphological characters, and taking nomenclatural stability into consideration. We suggest the recognition of eleven, morphologically well-defined and clearly monophyletic families, namely the Boraginaceae s.str., Codonaceae, Coldeniaceae fam. nov., Cordiaceae, Ehretiaceae, Heliotropiaceae, Hoplestigmataceae, Hydrophyllaceae, Lennoaceae, Namaceae, and Wellstediaceae. Descriptions, synonomy, a taxonomic key, and a list of genera for these eleven families are provided, including the new family Coldeniaceae (monogeneric) and Namaceae (segregated from Hydrophyllaceae and comprising Nama, Eriodictyon, Turricula, and Wigandia), the latter necessitating a revised circumscription of a more morphologically coherent Hydrophyllaceae.

Distinct sensitivity of fungal freshwater guilds to water quality

Multiple anthropogenic stressors have been shown to impact animal and plant communities in freshwater ecosystems, but the responses of aquatic fungi remain largely unknown. Stressor effects on fungal communities may, however, result in changes of decomposition of plant litter and, thus, impact nutrient cycling, a key process for ecosystem functioning. We tested the impact of increased chloride and sediment levels, as well as reduced water flow velocity, on eukaryotic freshwater communities, with an emphasis on fungi, in a mesocosm experiment. Each of the three stressors was applied individually and in all combinations in a full-factorial design. Litterbags with non-sterilised tree leaves and sterile ceramic tiles were added to the mesocosms, to analyse the responses of communities in decaying plant material and in biofilms. Fungi preferably occurring in biofilms were supposed to represent indigenous aquatic fungi, while litterbag communities should be predominantly composed of fungi known from terrestrial litter. Community composition was assessed by high-throughput sequencing of amplified barcoding regions. Similarity matrices of operational taxonomic unit (OTU) tables calculated by UCLUST and CD-HIT-OTU-Illumina were significantly correlated. Preferred occurrence in biofilm and litter communities, respectively, was used for the grouping of OTUs into three ecological guilds. Stressor sensitivity varied among the guilds. While non-fungal, in particular autotrophic, OTUs responded to several treatments, two of the fungal guilds, i.e. those exclusively colonising litter and those preferably occurring on the ceramic tiles, showed no response to any applied treatment. Only fungi preferably, but not exclusively, colonising litter significantly responded to chloride addition. Their distribution patterns again correlated significantly with those of non-fungal OTUs, indicating possible interdependencies between both groups. The results indicate that eukaryotic freshwater communities are composed of different guilds, with distinctive sensitivity and tolerance to anthropogenic stressors.

Mutualism in Yeasts

Yeasts are often associated with macro- and microorganisms, but these interactions can vary from mutually beneficial to antagonistic. In this chapter, we review mutually beneficial interactions involving yeasts. First, we describe some ways in which yeasts may benefit from the metabolism or actions of other species. Next, we describe the characteristics of yeasts that could benefit other organisms, including rapid growth, high nutrient content, detoxification, and the production of metabolic by-products. We highlight in detail a few of the types of interactions that most resemble mutualisms between yeasts and other organisms for: (1) yeast interactions with animals (vertebrate and invertebrate), (2) yeast interactions with plants, (3) yeast interactions with other microorganisms, and (4) multispecies interactions, including pollination. We necessarily focus on recently published work. We indicate where good evidence exists for mutualism and where more results will be required to demonstrate mutual benefit. Finally, we conclude the chapter with directions for future work, including how current technological approaches may be combined with manipulative experiments to allow rigorous tests of the mutualistic nature of yeast associations.

Impact of three different fungicides on fungal epi- and endophytic communities of common bean (Phaseolus vulgaris) and broad bean (Vicia faba)

ABSTRACT In this study, the impacts of three different fungicides to fungal phyllosphere communities on broad bean (Vicia faba, Fabaceae) and common bean (Phaseolus vulgaris, Fabaceae) were analyzed. The fungicides included copper, sulfur, and azoxystrobin. The plants were sowed, grown, and treated under conditions occurring in conventional and organic farming. A culture-based approach was used to identify changes in the phyllosphere fungal community after the treatment. Different effects on species richness and growth index of the epiphytic and endophytic communities for common bean and broad bean could be shown. Treatments with sulfur showed the weakest effect, followed by those based on copper and the systemic azoxystrobin, which showed the strongest effect especially on endophytic communities. The epiphytic fungal community took five weeks to recover after treatment with azoxystrobin. However, the effect of azoxystrobin on the endophytic community lasted more than five weeks. Finally, the data suggest that the surface structure of the host leaves have a huge impact on the mode of action that the fungicides exert.

Studies on Chromosome Numbers and Spore Size in Brazilian ＂Isoëtes＂

Abstract The lycophyte genus Isoëtes L. is nearly cosmopolitan, with approximately 350 species, 23 of which occur in Brazil. The lack of adequate distinguishing morphological characters in the leaves and stems, as well as the frequent cases of hybridization and polyploidy, makes the identification of species very difficult. Usually the spores provide the best characters for distinguishing species within Isoëtes, but these can vary in size because of polyploidy and hybridization. In this work we studied the variation in size of both mega- and microspores, and the relationship between size and ploidy level. We also present the first chromosome counts for seven species that are endemic to Brazil: I. goebelii (2n  =  33), I. martii (2n  =  44), I. maxima (2n  =  22), I. organensis (2n  =  66), I. ramboi (2n  =  44) I. smithii (2n  =  44), and I. spannagelii (2n  =  22). Our results suggest a correlation between ploidy level and spore size can be useful for the establishment of a preliminary hypothesis on polyploidy and hybridization among Brazilian Isoëtes.

Adaptive anonymity: Crypsis as an evolutionary trait of floral yeasts?

Nectar-dwelling yeast and bacteria are common inhabitants of flowers and evidently involved in pollination. The limited number of floral plant-pollinator models studied to date reveal inconsistent conclusions on microbial effects, but coincide with respect to high microbial specificity: while bacteria reduce visitation frequencies of pollinators, nectar-borne specialist yeasts (in contrast to allochthonous or transient species) impose none or even a beneficial effect on flower visitation. However, these findings are in conflict with the strong impact of these predominantly fermenting organisms on the nectar environment. In order to cope with the ultimate dependency of nectar-dwellers on repeated transportation by foragers as a result of early floral senescence, the modifications of nectar associated with specialist growth have been interpreted as adaptations that suit forager’s preferences. But, the development of foraging preferences to either axenic flowers or flowers colonized by specialist microorganisms would lead to a dead-end for nectar-dwellers, as the probability of inoculation into new suitable habitats would be reduced. Based on a critical survey of the available literature and an additional pollinator experiment where we find that the allochthonous species Cryptococcus victoriae negatively affects attraction and rewarding of floral visitors, while the specialist yeast Metschnikowia reukaufii does not, we propose the hypothesis that nectar-borne yeasts may have evolved to blend into their environment avoiding detection by pollinators, following the ecological concept of crypsis. Although, neither chemical nor olfactory crypsis has been reported for nectar-borne microorganisms, the attention to this mechanism in yeast dispersal needs to be directed in future studies.

A case of behavioural diversification in male floral function – the evolution of thigmonastic pollen presentation

Obvious movements of plant organs have fascinated scientists for a long time. They have been studied extensively, but few behavioural studies to date have dealt with them, and hardly anything is known about their evolution. Here, we present a large experimental dataset on the stamen movement patterns found in the Loasaceae subfam. Loasoideae (Cornales). An evolutionary transition from autonomous-only to a combination of autonomous and thigmonastic stamen movement with increased complexity was experimentally demonstrated. We compare the stamen movement patterns with extensive pollinator observations and discuss it in the context of male mating behavior. Thigmonastic pollen presentation via stamen movements appears to be a crucial component of floral adaptation to pollinator behaviour, evolving in concert with complex adjustments of flower signal, reward and morphology. We hypothesize that rapid adjustments of pollen presentation timing may play a significant role in the diversification of this plant group, representing a striking example for the evolutionary significance of plant behaviour.