Molecular Mechanisms Of Plant Reproductive Adaptation To Aridity Gradients

This book on lupin genomics primarily focuses on the narrow-leafed lupin (NLL), and details the genomic resources that have been developed and how they are currently being used to help advance both fundamental and applied research on NLL in areas ranging from its domestication to plant–microbe interactions and syntenic relationships between NLL and other legume crops. It also reports on genomic efforts being pursued with regard to other lupin crops. Lupins are important ecological ‘engineers’: they can colonise and thrive in low-nutrient soils due to their ability to fix atmospheric nitrogen in symbiosis with bacteria and efficiently take up phosphorous. Recently, lupins have attracted considerable interest, not only because of their value for sustainable farming as a break crop, but also as a potential ‘super food’ for fighting major health issues in connection with diabetes and obesity. Narrow-leafed lupin is the main grain legume crop, grown primarily in Australia, and was therefore selected for the development of a reference lupin genome and associated genomic resources. Its genome has recently been sequenced with a focus on the gene-rich space, which has advanced the development of new breeding tools for the improvement of NLL and related lupin crops.

The first stand-alone textbook for at least ten years on this increasingly hot topic in times of global climate change and sustainability in ecosystems. Ecological biochemistry refers to the interaction of organisms with their abiotic environment and other organisms by chemical means. Biotic and abiotic factors determine the biochemical flexibility of organisms, which otherwise easily adapt to environmental changes by altering their metabolism. Sessile plants, in particular, have evolved intricate biochemical response mechanisms to fit into a changing environment. This book covers the chemistry behind these interactions, bottom up from the atomic to the system's level. An introductory part explains the physico-chemical basis and biochemical roots of living cells, leading to secondary metabolites as crucial bridges between organisms and the respective ecosystem. The focus then shifts to the biochemical interactions of plants, fungi and bacteria within terrestrial and aquatic ecosystems with the aim of linking biochemical insights to ecological research, also in human-influenced habitats. A section is devoted to methodology, which allows network-based analyses of molecular processes underlying systems phenomena. A companion website offering an extended version of the introductory chapter on Basic Biochemical Roots is available at http://www.wiley.com/go/Krauss/Nies/EcologicalBiochemistry

The appearance of the new generation in higher plants is ensured by the presence of viable seeds in the mother plant. A good number of signaling networks is necessary to provoke germination. Phytohormones play a key role in all stages of seed development, maturation, and dormancy acquisition. The dormancy of some seeds can be relieved through a tightly regulated process called after-ripening (AR) that occurs in viable seeds stored in a dry environment. Although ABA is directly involved in dormancy, recent data suggest that auxin also plays a preponderant role. On the other hand, the participation of reactive oxygen species (ROS) in the life of the seed is becoming increasingly confirmed. ROS accumulate at different stages of the seed’s life and are correlated with a low degree of dormancy. Thus, ROS increase upon AR and dormancy release. In the last decade, the advances in the knowledge of seed life have been noteworthy. In this Special Issue, those processes regulated by DOG1, auxin, and nucleic acid modifications are updated. Likewise, new data on the effect of alternating temperatures (AT) on dormancy release are here present. On the one hand, the transcriptome patterns stimulated at AT that encompasses ethylene and ROS signaling and metabolism together with ABA degradation were also discussed. Finally, it was also suggested that changes in endogenous γ-aminobutyric acid (GABA) may prevent seed germination.

Respiration in plants, as in all living organisms, is essential to provide metabolic energy and carbon skeletons for growth and maintenance. As such, respiration is an essential component of a plant’s carbon budget. Depending on species and environmental conditions, it consumes 25-75% of all the carbohydrates produced in photosynthesis – even more at extremely slow growth rates. Respiration in plants can also proceed in a manner that produces neither metabolic energy nor carbon skeletons, but heat. This type of respiration involves the cyanide-resistant, alternative oxidase; it is unique to plants, and resides in the mitochondria. The activity of this alternative pathway can be measured based on a difference in fractionation of oxygen isotopes between the cytochrome and the alternative oxidase. Heat production is important in some flowers to attract pollinators; however, the alternative oxidase also plays a major role in leaves and roots of most plants. A common thread throughout this volume is to link respiration, including alternative oxidase activity, to plant functioning in different environments.

The papers herein are volume 1 of the proceedings of the 11th International Wheat Genetics Symposium, held in Brisbane, Australia, in 2008. The series presents the science of the genetic sciences applied to bread and durum wheats and other species.