The Editorial Office of Frontiers in Plant Science would like to thank all the Chief Editors, Associate Editors and Review Editors that played an integral part in Frontiers’ innovative Collaborative Peer-Review process in 2020. In particular, we would like to recognize and thank Prof. Joshua L. Heazlewood – our now former Field Chief Editor, for his commitment, support and enthusiasm for the Plant Science field. Josh’s dedication and leadership has helped Frontiers in Plant Science become the most cited journal in the field with a strong editorial community. Looking forward, we’re excited to welcome Prof. Yunde Zhao, as our new Field Chief Editor in 2021. Having been with Frontiers in Plant Science since 2017, Yunde has contributed extensively to the development of the journal and will continue to ensure the journal goes from strength to strength.

Besides increasing crop yield to feed the growing population, improving crop quality is a challenging and key issue. Indeed, quality determines consumer acceptability and increases the attractivity of fresh and processed products. In this respect, fruit and vegetables, which represent a main source of vitamins and other health compounds, play a major role in human diet. This is the case in developing countries where populations are prone to nutritional deficiencies, but this is also a pending issue worldwide, where the growing middle class is increasingly aware and in search of healthy food. So a future challenge for the global horticultural industry will be to answer the demand for better quality food in a changing environment, where many resources will be limited. This e-collection collates state-of-the-art research on the quality of horticultural crops, covering the underlying physiological processes, the genetic and environmental controls during plant and organ development and the postharvest evolution of quality during storage and processing.

Plant proteases are involved in most aspects of plant physiology and development, playing key roles in the generation of signaling molecules and as regulators of essential cellular processes such as cell division and metabolism. They take part in important pathways like protein turnover by the degradation of misfolded proteins and the ubiquitin-proteasome pathway, and they are responsible for post-translational modifications of proteins by proteolysis at highly specific sites. Proteases are also implicated in a great variety of environmentally controlled processes, including mobilization of storage proteins during seed germination, development of seedlings, senescence, programmed cell death and defense mechanisms against pests and pathogens. However, in spite of their importance, little is known about the functions and mode of actions of specific plant proteases. This Research Topic collects contributions covering diverse aspects of plant proteases research.

Plant diseases are destructive and threaten virtually any crop grown on a commercial scale. They are kept in check by plant breeding strategies that have introgressed disease resistance genes into many important crops, and by the deployment of costly control measures, such as antibiotics and fungicides. However, the capacity for the agents of plant disease - viruses, bacteria, fungi, and oomycetes - to adapt to new conditions, overcoming disease resistance and becoming resistant to pesticides, is very great. For these reasons, understanding the biology of plant diseases is essential for the development of durable control strategies. Plant-Pathogen Interactions provides and overview of our current knowledge of plant-pathogen interactions and the establishment of plant disease, drawing together fundamental new information on plant infection mechanisms and host responses. The role of molecular signals, gene regulation, and the physiology of pathogenic organisms are emphasized, but the role of the prevailing environment in the conditioning of disease is also discussed. Emphasizing the broader understanding that has emerged from the use of molecular genetics and genomics, Plant-Pathogen Interactions highlights those interactions that have been most widely studied and those in which genome information has provided a new level of understanding.

This book provides readers a fundamental understanding of the science and applications of medicinal and aromatic plant materials. Chapters of this handbook covers the basics of ethnobotany, (bio)active compounds and their natural sources. Information about the cosmetic, nutritional, medicinal and industrial uses (dyes, tannins and biocides) is also presented. Readers will also learn about concepts central to quality control processes, sustainable management, wild harvesting and the economic valuation of the industrial impact of endemic plants. The volume also presents a case study of the wormwood (Artemisia absinthium L.), which is helpful in explaining the above concepts. This book is intended as a handbook for undergraduate students and teaching professionals in research and higher education institutions involved in agricultural engineering, pharmacy, forestry, natural product chemistry. Non experts interested in aromatic and medicinal plant agriculture, transformation and commercialization will also find the content informative.

Over the past decade, progress in plant science and molecular technologies has grown considerably. This book focuses on plant biotechnology applications specializing in certain aspects of breeding and molecular marker-assisted selection processes, omic strategies, usage of bioinformatic tools, and nanotechnological improvements in agricultural sciences. Most farmers and breeders can no longer simply turn to the older strategies, and new instructions are needed to adapt their systems to achieve their production goals. The book covers new information on using metabolomics and nanotechnology in agriculture. In these circumstances, all new data and technology are very important in plant science. The topics in this book are practical and user-friendly. They allow practitioners, students, and academicians with specific background knowledge to feel confident about the principles presented on a new generation of molecular plant biotechnology applications.

The classic case for why government must support science—with a new essay by physicist and former congressman Rush Holt on what democracy needs from science today Science, the Endless Frontier is recognized as the landmark argument for the essential role of science in society and government’s responsibility to support scientific endeavors. First issued when Vannevar Bush was the director of the US Office of Scientific Research and Development during the Second World War, this classic remains vital in making the case that scientific progress is necessary to a nation’s health, security, and prosperity. Bush’s vision set the course for US science policy for more than half a century, building the world’s most productive scientific enterprise. Today, amid a changing funding landscape and challenges to science’s very credibility, Science, the Endless Frontier resonates as a powerful reminder that scientific progress and public well-being alike depend on the successful symbiosis between science and government. This timely new edition presents this iconic text alongside a new companion essay from scientist and former congressman Rush Holt, who offers a brief introduction and consideration of what society needs most from science now. Reflecting on the report’s legacy and relevance along with its limitations, Holt contends that the public’s ability to cope with today’s issues—such as public health, the changing climate and environment, and challenging technologies in modern society—requires a more capacious understanding of what science can contribute. Holt considers how scientists should think of their obligation to society and what the public should demand from science, and he calls for a renewed understanding of science’s value for democracy and society at large. A touchstone for concerned citizens, scientists, and policymakers, Science, the Endless Frontier endures as a passionate articulation of the power and potential of science.

Natural-based substances, ‘plant biostimulants’, have been considered as environmentally friendly alternatives to agrichemicals. Biostimulants may comprise microbial inoculants, humic acids, fulvic acids, seaweed extracts, etc. These biostimulants have biopesticide and biostimulant utilities. Elucidations on direct or microbially mediated functions of biostimulants are presented in this book to illustrate fundamental principles and recent applications underlying this technology. This book has encompassed a cross-section of topics on different concepts to describe effective strategies by using these substances and/or beneficial microorganisms within sustainable agroecosystems. I sincerely hope that the information provided adequately reflects the objectives of this compilation. “One of the first conditions of happiness is that the link between man and nature shall not be broken.” Leo Tolstoy

The onset of flowering is an important step during the lifetime of a flowering plant. During the past two decades, there has been enormous progress in our understanding of how internal and external (environmental) cues control the transition to reproductive growth in plants. Many flowering time regulators have been identified from the model plant Arabidopsis thaliana. Most of them are assembled in regulatory pathways, which converge to central integrators which trigger the transition of the vegetative into an inflorescence meristem. For crop cultivation, the time of flowering is of upmost importance, because it determines yield. Phenotypic variation for this trait is largely controlled by genes, which were often modified during domestication or crop improvement. Understanding the genetic basis of flowering time regulation offers new opportunities for selection in plant breeding and for genome editing and genetic modification of crop species.