SPECIAL ISSUES & COLLECTIONS 2013
The objectives of this paper are to summarize the principles of root/rhizosphere management and provide an overview of some successful case studies on how to exploit the biological potential of root system and rhizosphere processes to improve crop productivity and nutrient use efficiency.
The purpose of this review is to explore some of the ways in which understanding root systems and their interactions with soils could contribute to the development of more sustainable systems of intensive production. Physical interactions with soil particles limit root growth if soils are dense, but root–soil contact is essential for optimal growth and uptake of water and nutrients.
To gain an understanding of how apoplastic ROS levels change under water stress, cerium chloride staining was used in conjunction with transmission electron microscopy to examine the spatial distribution of apoplastic H2O2. The results revealed that apoplastic H2O2 levels increased specifically in the apical region of the growth zone under water stress, correlating spatially with the maintenance of cell elongation.
Here we review how soil conditions influence root system architecture; focusing on cereals. Cereals provide half of human calories, and their root systems differ from those of dicotyledons. We find that few controlled-environment studies combine more than one soil stimulus and, those that do, highlight the complexity of responses.
On the move: Induced resistance in monocots. Balmer et al.
Although plants possess an arsenal of constitutive defences such as structural barriers and preformed antimicrobial defences, many attackers are able to overcome the pre-existing defence layers. In this review, current facts and trends concerning basal immunity, and systemic acquired/induced systemic resistance in the defence of monocots against pathogens and herbivores will be summarized.
Microbial recognition and evasion of host immunity. Pel and Pieterse
Evasion of host immune recognition is less well studied but is emerging as another important strategy. Escape from recognition by the host’s immune system can be caused by alterations in the structure of the recognized MAMPs, or by active intervention of ligand-receptor recognition. This paper reviews the structure and recognition of common MAMPs and the ways that plant-associated microbes have evolved to prevent detection by their host.
Root herbivores are important ecosystem drivers and agricultural pests, and, possibly as a consequence, plants protect their roots using a variety of defensive strategies. One aspect that distinguishes belowground from aboveground plant–insect interactions is that roots are constantly exposed to a set of soil-specific abiotic factors. These factors can profoundly influence root resistance, and, consequently, the outcome of the interaction with belowground feeders. In this review, we synthesize the current literature on the impact of soil moisture, nutrients, and texture on root–herbivore interactions.
Since induced resistance is a host response, its expression under field conditions is likely to be influenced by a number of factors, including the environment, genotype, crop nutrition and the extent to which plants are already induced. Although research in this area has increased over the last few years, our understanding of the impact of these influences on the expression of induced resistance is still poor.
Priming of plant immune responses, alterations in phytohormone homeostasis, regulation of iron homeostasis, silicon-driven photorespiration and interaction with defence signalling components all are potential mechanisms involved in regulating silicon-triggered resistance responses. Further elucidating how silicon exerts its beneficial properties may create new avenues for developing plants that are better able to withstand multiple attackers.
The molecular architecture of the plant nuclear pore complex. Tamura and Hara-Nishimura
The nucleus contains the cell’s genetic material, which directs cellular activity via gene regulation. In this review, we summarize the current knowledge regarding the plant NPC proteome and address structural and functional aspects of plant nucleoporins, which support the fundamental cellular machinery.
The plant nuclear pore complex (NPC) is a critical controlling element in this nucleocytoplasmic movement of protein and RNA. The NPC is comprised of approximately 30 nucleoporin proteins arranged in radial symmetry around the central pore. Here is presented an overview as to how the members of the plant NPC affect signalling pathways, highlighting the progress and difficulties within this research area.
Taking transgenic rice drought screening to the field Gaudin et al.
The molecular architecture of the plant nuclear pore complex Tamura & Hara-Nishimura
In this review, we discuss recent advancements in CP29 phosphorylation and dephosphorylation studies and its physiological significance under environmental stresses in higher plants, especially in the monocotyledonous crops
This review combines analyses of transcriptomic, metabolomic, and proteomic data, and fruit process-based simulation models of the accumulation of citric and malic acids, to further our understanding of the physiological mechanisms likely to control the accumulation of these two acids during fruit development.
Sweet immunity in the plant circadian regulatory network Bolouri Moghaddam & Van den Ende
Emerging roles of microRNAs in the mediation of drought stress response in plants Y Ding, Y Tao, and C Zhu
Drought is a major environmental stress factor that limits agricultural production worldwide. This review summarizes recent molecular studies on the miRNAs involved in the regulation of drought-responsive genes, with emphasis on miRNA-associated regulatory networks involved in drought stress response.
Photo-oxidative stress in emerging and senescing leaves: a mirror image? M Juvany, M Müller, and S Munné-Bosch
This review focuses on the role of photo-oxidative stress both at early stages of leaf growth and during leaf senescence. We consider early leaf growth to be the stages at which the leaf is photosynthetically active but still depends on imported photoassimilates for net growth. During leaf senescence, we focus on the processes involved in the initiation, re-organization and terminal phases. Furthermore, we aim at characterizing such processes beyond the information gathered in the model plant Arabidopsis thaliana and include recent literature on the topic obtained in perennials.
The key roles of Ca2+-ATPases in transport systems and stress signalling in cellular homeostasis are addressed in this review. A complete understanding of plant defence mechanisms under stress will allow bioengineering of improved crop plants, which will be crucial for food security currently observed worldwide in the context of global climate changes. Overall, this article covers classification, evolution, structural aspects of Ca2+-ATPases, and their emerging roles in plant stress signalling.
This review discusses changes in the normal pattern of signal transduction that could account for disruption of guard cell signalling after long-term exposure to some environmental conditions, with special emphasis on long-term low vapour pressure deficit (VPD).
Making open data work for plant scientists Leonelli et al.
Here we highlight some of the challenges encountered by plant researchers at the bench when generating, interpreting and attempting to disseminate their data. We review the difficulties involved in sharing sequencing, transcriptomics, proteomics and metabolomics data. We then identify and assess the benefits and drawbacks of three data sharing venues currently available to plant scientists: (1) journal publication; (2) university repositories; and (3) community and project-specific databases.
A criticism of the value of midparent in polyploidization Alberto Gianinetti
Genetic additivity occurs when the effects of different alleles, or different genes, add up in the resulting phenotype. Non-additive effects (genetic interactions) are typically measured as deviations from MPV. Recently, however, the use of MPV has been directly transposed to the study of genetic additivity in newly synthesized plant polyploids, assuming that they should as well display mid-parent expression patterns for additive traits. Here, it is shown that this direct transposition is incorrect.
This review outlines the problems with existing hybrid wheat breeding systems and explores molecular-based technologies that could improve the hybrid production system to reduce hybrid seed production costs, a pre-requisite for a commercial hybrid wheat system.