Diethylpyrocarbonate—An effective agent for the sterilization of different types of nutrient media

A simple and convenient method has been tested for the steriltzation of nutrient media for long-term cultivation of plant cells. Diethylpyrocarbonate is suitable for this task in concentrations about 1000 mg l^-1 The cells cultivated for 15 subsequent passages on media treated by DPC had the same growth parameters, production pattern and ability to transform exogeneous organic compounds as did the controls. The method is suitable for the preparatian of both liquid and agar media, for stabilization of stock solutions and for sterilization of cultivation vessels and tubing.Abbreviations DPC diethylpyrocarbonate - medium MS nutrient medium according to Murashige and Skoog - NAA naphtaleneacetic acid     

Epigenetic inheritance and plant evolution

Being sessile organisms, plants show a high degree of developmental plasticity to cope with a constantly changing environment. While plasticity in plants is largely controlled genetically, recent studies have demonstrated the importance of epigenetic mechanisms, especially DNA methylation, for gene regulation and phenotypic plasticity in response to internal and external stimuli. Induced epigenetic changes can be a source of phenotypic variations in natural plant populations that can be inherited by progeny for multiple generations. Whether epigenetic phenotypic changes are advantageous in a given environment, and whether they are subject to natural selection is of great interest, and their roles in adaptation and evolution are an area of active research in plant ecology. This review is focused on the role of heritable epigenetic variation induced by environmental changes, and its potential influence on adaptation and evolution in plants.     

Inclusion of phytosociological data in an index of vegetation fire danger: application and mapping on the Karst area around Trieste (Italy)

In this paper we propose a method to produce maps of fire danger index (FDI). The index includes in the formula a vegetation pyrogenic potential index (VPPI) based on floristic phytosociological data. The map of FDI is produced by integrating available phytosociological maps of vegetation, geomorphology and climate, using the Geographic Information System technology. The method is applied to an area of the coastal Classical Karst (NE-Italy). While fire risk maps based on the incidence of previous fires are useful for facilitating emergency operations, e.g. the allocation of fire fighting resources, we conclude that the proposed index offers an effective tool to plan actions for fire prevention.     

Are ants botanists? Ant associative learning of plant chemicals mediates foraging for carbohydrates

1. Although associative learning is widespread across animals, its ecological importance is difficult to assess because learning is rarely studied in the field, where informative cues are juxtaposed against complex backgrounds of uninformative noise. 2. Ants rely heavily on chemical cues for foraging and engage in many ecologically important interactions with plants. Nevertheless, little is known about the role of associative learning of plant chemicals in ant foraging for carbohydrates. 3. In a field setting, the present study investigated whether the distantly related ant species Formica podzolica (Formicinae subfamily) and Tapinoma sessile (Dolichoderinae subfamily) exhibited associative learning of the chemical cues from two co-occurring plant species that are taxonomically and chemically distinct (Asteraceae: Helianthella quinquenervis and Apiaceae: Ligusticum porteri). 4. For two consecutive summers, ants were trained to forage from artificial sugar-rich baits associated with the leaf chemicals from either H. quinquenervis or L. porteri for 24 h, after which a two-choice test was deployed to assess whether ants would be more likely to select baits associated with the same (versus different) plant chemicals on which they had been trained. 5. The present study demonstrates associative learning of chemicals from both plant species, and these effects were consistent between ant species and years; training increased bait occupancy from 42% on the untrained scent to 66% on the trained scent. These results indicate that associative odour-learning may be widespread across ants and serve as an important mechanism mediating ant selection of resources.     

Green land: Multiple perspectives on green algal evolution and the earliest land plants

Green plants, broadly defined as green algae and the land plants (together, Viridiplantae), constitute the primary eukaryotic lineage that successfully colonized Earth's emergent landscape. Members of various clades of green plants have independently made the transition from fully aquatic to subaerial habitats many times throughout Earth's history. The transition, from unicells or simple filaments to complex multicellular plant bodies with functionally differentiated tissues and organs, was accompanied by innovations built upon a genetic and phenotypic toolkit that have served aquatic green phototrophs successfully for at least a billion years. These innovations opened an enormous array of new, drier places to live on the planet and resulted in a huge diversity of land plants that have dominated terrestrial ecosystems over the past 500 million years. This review examines the greening of the land from several perspectives, from paleontology to phylogenomics, to water stress responses and the genetic toolkit shared by green algae and plants, to the genomic evolution of the sporophyte generation. We summarize advances on disparate fronts in elucidating this important event in the evolution of the biosphere and the lacunae in our understanding of it. We present the process not as a step-by-step advancement from primitive green cells to an inevitable success of embryophytes, but rather as a process of adaptations and exaptations that allowed multiple clades of green plants, with various combinations of morphological and physiological terrestrialized traits, to become diverse and successful inhabitants of the land habitats of Earth.     

A global synthesis of the effects of diversified farming systems on arthropod diversity within fields and across agricultural landscapes

Agricultural intensification is a leading cause of global biodiversity loss, which can reduce the provisioning of ecosystem services in managed ecosystems. Organic farming and plant diversification are farm management schemes that may mitigate potential ecological harm by increasing species richness and boosting related ecosystem services to agroecosystems. What remains unclear is the extent to which farm management schemes affect biodiversity components other than species richness, and whether impacts differ across spatial scales and landscape contexts. Using a global metadataset, we quantified the effects of organic farming and plant diversification on abundance, local diversity (communities within fields), and regional diversity (communities across fields) of arthropod pollinators, predators, herbivores, and detritivores. Both organic farming and higher in‐field plant diversity enhanced arthropod abundance, particularly for rare taxa. This resulted in increased richness but decreased evenness. While these responses were stronger at local relative to regional scales, richness and abundance increased at both scales, and richness on farms embedded in complex relative to simple landscapes. Overall, both organic farming and in‐field plant diversification exerted the strongest effects on pollinators and predators, suggesting these management schemes can facilitate ecosystem service providers without augmenting herbivore (pest) populations. Our results suggest that organic farming and plant diversification promote diverse arthropod metacommunities that may provide temporal and spatial stability of ecosystem service provisioning. Conserving diverse plant and arthropod communities in farming systems therefore requires sustainable practices that operate both within fields and across landscapes.