Preface

Over the decades, the entire world has faced critical crises, primarily due to the expanding human population resulting in environmental pollution, food shortages, and the potential exacerbation of these issues under the scenario of global climate change. Scientists are expected to address these problems by exploring knowledge in plant physiology, with a specific focus on stress-tolerant mechanisms. This exploration can significantly advance agricultural biotechnology and breeding, specifically concentrating on improving crop resilience to climate change. The goal is to enhance both the yield and quality of crops, contributing to global food security. Therefore, there is a growing demand to expand our understanding of developing climate-resilient crops.

This volume offers updated methods and current applications of genome editing technology, outlining strategies to enhance drought tolerance in crops. The underlying mechanism centralizes modified cell signaling through precision mutagenesis introduced by CRISPR/Cas-mediated genome editing. CRISPR-edited plants exhibit a re-programmed balance and interconnections of plant hormones, including abscisic acid and cytokinins, attributed to edited versions of transcription factors and cytokinin oxidase/dehydrogenases.

An alternative solution to address climate-related abiotic stresses is explored through eco-friendly organic farming approaches. This volume provides a comprehensive summary of organic farming systems to alleviate abiotic stress responses in crops. It covers the application of bio-fertilizers, bio-priming with plant growth-promoting microorganisms, bio-stimulants, and organic manures. Additionally, smart agronomic practices under stress conditions, such as crop rotation, grafting, intercropping, selection of resistant/tolerant varieties, sowing methods and timing, tillage, and the use of organic formulations, are discussed.

In the face of the modern world's energy shortage, this book explores promising solutions, with a focus on exploiting alternative energy sources. It summarizes current achievements in green-energy technology, specifically artificial photosynthesis systems. These systems have the potential to increase clean energy sources like carbon monoxide, formic acid, methane, and pure hydrogen by designing an advanced photosynthetic system. The book not only illustrates mechanistic insights into photosynthetic chemistry but also comprehensively discusses the limitations and future directions of applied photosynthesis approaches. Despite these limitations, scientists are actively working to improve artificial photosynthesis systems, aiming for future technology that is more cost-effective, robust, and scalable.

In this volume, various interesting subtopics of plant physiology and cross-field observations are proposed. For instance, a biochemistry perspective on the dissociation of water to produce oxygen in plants is presented, with the intention of inspiring readers to design future experiments for further clarification. Additionally, a discussion on the potential role of a 'robber tree' and insights into plant reproductive strategies is put forth, suggesting their potential applications in agriculture in the future.

This book is an ideal reference for students, teachers, and scientists in the field of plant science. Specifically, researchers focusing on subtopics of plant stress physiology, plant biochemistry, photosynthesis, and crop breeding are highly recommended.

> **Jen-Tsung Chen** Department of Life Sciences, National University of Kaohsiung, Kaohsiung, Taiwan

## **Chapter 1**
