Characterizing membrane anchoring of leaf-form ferredoxin-NADP+ oxidoreductase in rice

Leaf-form ferredoxin-NADP+ oxidoreductases (LFNRs) function in the last step of the photosynthetic electron transport chain, exist as soluble proteins in the chloroplast stroma, and are weakly associated with thylakoids or tightly anchored to chloroplast membranes. Arabidopsis thaliana has two LFNRs, and the chloroplast proteins AtTROL (THYLAKOID RHODANESE-LIKE PROTEIN) and AtTIC62 (62-kDa SUBUNIT OF TRANSLOCON OF INNER CHLOROPLAST MEMBRANE) participate in anchoring AtLFNRs to the thylakoid membrane. By contrast, the membrane anchoring mechanism of rice (Oryza sativa) LFNRs has not been elucidated. Here, we investigated the membrane-anchoring mechanism of LFNRs and its physiological roles in rice. We characterized the rice protein OsTROL1 based on its homology to AtTROL and showed that OsTROL1 is also a thylakoid membrane anchor and its loss led to a compensatory increase in OsTIC62. Moreover, OsLFNR1 attachment through a membrane anchor depends on OsLFNR2, unlike their Arabidopsis counterparts. In addition, OsTIC62 was more highly expressed in rice under dark than under light conditions, consistent with the increased membrane binding of OsLFNR in the dark. Moreover, we observed reciprocal stabilization between OsLFNRs and their membrane anchors. Therefore, our study sheds light on the mechanisms anchoring LFNRs to membranes in rice and highlights differences with Arabidopsis

Exploration of nature-based biomimetic approach in landscape architectural design: parametric study of candelabra model design

This research provides an exploration of a biomimetic approach in the process of designing a candelabra model using linear shaped leaves of a Bell flower. The design process described in this research contains two steps: biological and geometrical. In the first biological step, a proper model for the creation of an urban element was found from nature in a Bell flower (Campanula persicifolia L.). The upper leaves of the selected plant, which are small with a linear spear and sharpening at the top, were chosen for the modeling process. The second step included applying two geometrical methods, i.e., Voronoi diagrams and Delaunay triangulation. A geometrical leaf form of the selected plant species and the modeling process were obtained using aparametric modeling software, Blender. Using different Blender plug-ins and modifiers, Delaunay triangulation and Voronoi diagram were implemented by marking the starting points on the leaf form in the image data source, adjusting the Delaunay triangulation parameters, and creating Voronoi diagrams in which the Voronoi points were located at the shortest distance from the edges of the Voronoi polygon. Consequently, a three dimensional model of a candelabra was developed through this study.

Adaptation and Some Quality Parameters of Cool Season Turfgrass Species in Samsun Conditions

The aim of this study is to determine adaptation and quality parameters of some cool season turfgrass cultivars and species, In the scope of this study, leaf form, variation of leaf colour according to the seasons, tiller number, thinning ratio, weed ratio and general appearance of the species were determined. The experiment was established according to confounding design with four replications in Samsun Conditions at November, 2010. According to 1000 seed weight and characteristics of the plants seeding ratios were determined as pure and viable seed as follows; Lolium perenne 40 g m-2, Festuca rubra var. rubra and Festuca rubra var. commutata 30 g m-2, Festuca arundinacea 40 g m-2, Poa pratensis 20 g m-2, Festuca rubra trichophylla 30 g m-2, Agrostis stolonifera and Agrostis tenuis 5 g m-2, Festuca ovina 25 g m-2. According to the results obtained from this study it was determined that species/cultivars have some superiority to each other because of their different morphological and physiological characteristics. When we consider weed competition, Lolium perenne and Festuca arundinaceae cultivars have to be added to the mixture in order to decrease weed competition. There was colour variation distinctively depending on the seasons for all species. But, compare to the others, cultivars of Agrostis sp. and Poa pratensis cultivars have the potential to keep leaf colour in different seasons. Leaf form and appearance of Festuca rubra, Poa trivialis and Festuca ovina are better than the others. In order to keep good conditions of turfgrass areas, especially after cutting in summer period, Poa pratensis and Poa trivialis should added in mixtures to get benefit their higher regenerating power.

Convergent origin of the narrowly lanceolate leaf in the genus Aster—with special reference to an unexpected discovery of a new Aster species from East China

Narrowly lanceolate leaves occur frequently in the genus Aster. It was often employed as a distinguishing character in the taxonomy of this genus. The origin of this particular leaf shape, however, has never been investigated using comparative methods. In this study, we reconstructed a comprehensive phylogeny that includes most species of Aster with narrowly lanceolate leaf. We then gathered data on riparian habitats and the presence or absence of narrowly lanceolate leaves, and investigated the evolutionary association between them in a phylogenetic context. Our analysis indicated that the species with narrowly lanceolate leaves are nested in unrelated lineages of the genus Aster, implying that they originated independently several times. Using Pagel’s comparative method of discrete data, we demonstrated a significant correlation between riparian habitats and narrowly lanceolate leaves. We further inferred the sequence of transition of the two characters. This analysis indicated that the sequence of evolution of riparian habitat and narrowly lanceolate leaf form was usually uncertain, but some positive results showed that the occurrence of riparian habitats may not precede the evolution of narrowly lanceolate leaf form. This study provided new insights into the adaptive evolution in a mega-diverse family. In addition, Aster tonglingensis, an unexpected new species with narrowly lanceolate leaves, was discovered and established based on the evidence from morphology, micromorphology and molecular phylogeny.

Variability of quantitative and qualitative characteristics of Populus × sibirica G.V. Krylov & G.V. Grig. ex A.K. Skvortsov

The purpose of this work is to identify the level of phenotypic diversity of the morphological features of Populus × sibirica leaves, including qualitative signs-phenes. To reveal the variability, the authors examined 90 trees, on which 1,350 leaves were measured in the green areas of the cities of Novosibirsk, Novokuznetsk and Berdsk. When analyzing the qualitative features, there were selected the following morphological markers: leaf pubescence, development of basal glands, leaf form, its base and apex. The conducted studies of Populus × sibirica samples showed that it is characterized by very low and low variability of the quantitative traits of a leaf. Leaf-shaped ovoid plates and leaves with developed basal glands (78–89 %) are predominant. Close indicators of averaged endogenous and individual variability reflect its cultural origin. Probably, Populus × sibirica in the Siberian region consists of several clones selected from the same hybrid family. A number of studied morphological qualitative features of a leaf, which are distinguished by the absence of endogenous variability, can be attributed to phenes: the shape of the apex and the shape of the base of the lamina, as well as the nature of the development of pubescence. The most controversial issue in the origin of Populus × sibirica remains the presence of basal glands at the base of the leaf blade.