Plant Science: Botany

The study of plant cell physiology is currently experiencing a profound transformation. Novel techniques allow dynamic in vivo imaging with subcellular resolution, covering a rapidly growing range of plant cell physiology. Several basic biological questions that have been inaccessible by the traditional combination of biochemical, physiological and cell biological approaches now see major progress. Instead of grinding up tissues, destroying their organisation, or describing cell- and tissue structure, without a measure for its function, novel imaging approaches can provide the critical link between localisation, function and dynamics. Thanks to a fast growing collection of available fluorescent protein variants and sensors, along with innovative new microscopy technologies and quantitative analysis tools, a wide range of plant biology can now be studied in vivo, including cell morphology & migration, protein localization, topology & movement, protein-protein interaction, organelle dynamics, as well as ion, ROS & redox dynamics.

The author reflects on her exploration of the plant world. She was invited to do a joint presentation on Seeing Plants: Visualization in Plant Biology at a BioQUEST educational symposium in Chicago, Illinois. She also took a course called Plant Morphology for Botanical Illustrators at the New York Botanical Garden.

As sessile organisms that are unable to escape from inhospitable environments, plants are at the mercy of the elements. Nonetheless, plants have
managed to adapt, evolve and survive in some of the harshest conditions
on earth. The FEBS Workshop ‘Adaptation Potential in Plants’, held at
the Gregor Mendel Institute of Molecular Plant Biology, Vienna, Austria
from 19 to 21 March 2009, provided a forum (including 18 invited talks,
8 selected short talks and 69 posters) for about 100 plant biologists from
32 countries, working in the diverse fields of genetics, epigenetics, stress
signalling, and growth and development, to come together and discuss
adaptation potential in plants at all its levels.

Biodeterioration, the alteration caused by living organisms, on historical buildings and
stone monuments is a well-known problem affecting two-thirds of the world’s cultural
heritage. The study of the flora growing on wall surface is of particular importance for
the assessment of the risk of biodeterioration of stone artifacts by vascular plants, and
for maintenance planning. In this study, we investigate how rock type, exposure and
inclination of the wall affect the biodeteriogenic flora at 13 sites of the Archaeological
Park of the Phlegraean Fields located in the province of Naples, in southern Italy. For
each site, we analysed randomly selected square areas with 2×2m size, representing
the different vegetation types in terms of vascular plant species cover. The total number of plant species recorded was 129, belonging to 43 families. Erigeron sumatrensis,
Sonchus tenerrimus and Parietaria judaica are the most commonly reported species,
while Capparis orientalis is the species with the highest average coverage. Substrate
type, exposure and surface inclination affect the floristic composition, with the average
plant cover significantly higher on vertical surfaces and at western and southern exposure. All the main biodeteriogenic vascular plant species grow on more or less porous
lythotype like yellow tufa, conglomerate and bricks. Finally, woody plants eradications
methods are proposed by the tree cutting and local application of herbicides, to avoid
stump and root sprouting and to minimize the dispersion of chemicals in the surrounding environment.

Hybridization is a key mechanism for increased diversification and speciation among modern plants and is especially important in certain families such as Rosaceae and Anacardiaceae. This mechanism is found to occur most commonly in areas of ecological disturbance, distribution, and migration. Resulting hybrid individuals have characteristic intermediate or mosaic patterns that combine those of the two parents in morphologically distinct and identifiable ways. The diverse latest Early Eocene flora of Republic, Washington, USA, is among the most collected of the Okanagan Highlands floras. This fossil flora includes relatives of modern taxa that are known to hybridize and produce characteristic patterns of leaf morphology and venation (Rosaceae; Anacardiaceae). In this study, we document patterns found in representative fossil leaves that are comparable to those indicative of hybridization in the modern relatives. We use the genera Sorbus L. (Rosaceae) and Rhus L. (Anacardiaceae) as models to demonstrate potential hybridization in the latest Early Eocene.

Published estimates on the paleoclimate of the Florissant fossil beds site of Colorado (34.1 Ma) have led to extremely different estimates of paleoelevation. The purpose of this paper is to review the paleoclimate methods used and to add the coexistence approach (CA) method to estimate paleotemperature for the Florissant site. The basis of the CA method is the dependence on overlapping climatic requirements for different taxa in the flora and their nearest living relatives. These relationships tie the fossil identities to the actual plant habitats and climatic requirements of close relatives. Based on the CA method, we conclude that the mean annual temperature ranged between 14.3 and 18.2 °C. These results support the conclusions offered by several other studies that the Florissant was a warm temperate to subtropical flora, and they are consistent with recent conclusions by structural geologists as well as other studies, indicating that the Florissant site was deposited at a relatively low elevation, probably between 1 and 1.5 km.

The Canadian Arctic Archipelago is a vast region of approximately 1,420,000 km2 , with a flora characterized by low species diversity, low endemicity, and little influence by alien species. New records of vascular plant species are documented here based on recent fieldwork on Victoria and Baffin Islands; additional records based on recent literature sources are mentioned. This paper serves as an update to the 2007 publication Flora of the Canadian Arctic Archipelago, and brings the total number of vascular plants for the region to 375 species and infraspecific taxa, an increase of 7.7%. Three families (Amaranthaceae, Juncaginaceae, Pteridaceae) and seven genera (Cherleria L., Cryptogramma R. Br., Platanthera Rich., Sabulina Rchb., Suaeda Forssk. ex
J.F. Gmel., Triglochin L., Utricularia L.) are added to the flora, and one genus is deleted (Minuartia L.). Five species are first records for Nunavut (Arenaria longipedunculata Hultén, Cryptogramma stelleri (S.G. Gmel.) Prantl, Puccinellia banksiensis Consaul, Saxifraga eschscholtzii Sternb., Utricularia ochroleuca R.W. Hartm.)