Publications

Global climate variations induce extreme temperatures and significantly decrease crop production, leading to food insecurity worldwide. Temperature extremes (mainly cold stress (CS): chilling 0–15 °C and freezing <0 °C temperatures) limit plant growth and development and severely affect plant physiology and biochemical and molecular processes. Subsequently, plants execute numerous endogenous mechanisms, including phytohormone biosynthesis (i.e., abscisic acid, cytokinins, jasmonic acid, salicylic acid, gibberellic acid, brassinosteroids, indole-3-acetic acid, ethylene, and strigolactones) to tolerate stressful environments. Phytohormones are vital for managing diverse events associated with plant growth and development under CS as important endogenous signaling substances that dynamically arbitrate many physiological, biochemical, and molecular responses through a stress-responsive regulatory cascade. This review briefly appraises plant responses and adaptation mechanisms to CS and then comprehensively reports on the crucial role of several phytohormones in adjusting the CS response for plant acclimation. We also discuss phytohormone-regulated genes controlling CS tolerance and their genetic engineering to combat CS in diverse plant species and develop future CS-smart crop plants. The potential of state-of-the-art omics approaches to help identify phytohormone-induced novel genes, metabolites, and metabolic pathways is also discussed. In short, we conclude that the exogenous application of phytohormones and genetic engineering of phytohormones-regulated genes are promising techniques for developing cold-smart crop plants.

Light-harvesting chlorophyll a/b-binding protein (LHCP) is one of the most abundant chloroplast proteins in plants. Its main function is to collect and transfer light energy to photosynthetic reaction centers. However, the roles of different LHCPs in light-harvesting antenna systems remain obscure. Exploration of nucleotide variation in the genes encoding LHCP can facilitate a better understanding of the functions of LHCP. In this study, nucleotide variations in Lhcb1, a LHCP gene in barley, were investigated across 292 barley accessions collected from 35 different countries using EcoTILLING technology, a variation of the Targeting Induced Local Lesions In Genomes (TILLING). A total of 23 nucleotide variations were detected including three insert/deletions (indels) and 20 single nucleotide polymorphisms (SNPs). Among them, 17 SNPs were in the coding region with nine missense changes. Two SNPs with missense changes are predicted to be deleterious to protein function. Seventeen SNP formed 31 distinguishable haplotypes in the barley collection. The levels of nucleotide diversity in the Lhcb1 locus differed markedly with geographic origins and species of accessions. The accessions from Middle East Asia exhibited the highest nucleotide and haplotype diversity. H. spontaneum showed greater nucleotide diversity than H. vulgare. Five SNPs in Lhcb1 were significantly associated with at least one of the six agronomic traits evaluated, namely plant height, spike length, number of grains per spike, thousand grain weight, flag leaf area and leaf color, and these SNPs may be used as potential markers for improvement of these barley traits.

Genetic modifications are made through diverse mutagenesis techniques for crop improvement programs. Among these mutagenesis tools, the traditional methods involve chemical and radiation-induced mutagenesis, resulting in off-target and unintended mutations in the genome. However, recent advances have introduced site-directed nucleases (SDNs) for gene editing, significantly reducing off-target changes in the genome compared to induced mutagenesis and naturally occurring mutations in breeding populations. SDNs have revolutionized genetic engineering, enabling precise gene editing in recent decades. One widely used method, homology-directed repair (HDR), has been effective for accurate base substitution and gene alterations in some plant species. However, its application has been limited due to the inefficiency of HDR in plant cells and the prevalence of the error-prone repair pathway known as non-homologous end joining (NHEJ). The discovery of CRISPR-Cas has been a game-changer in this field. This system induces mutations by creating double-strand breaks (DSBs) in the genome and repairing them through associated repair pathways like NHEJ. As a result, the CRISPR-Cas system has been extensively used to transform plants for gene function analysis and to enhance desirable traits. Researchers have made significant progress in genetic engineering in recent years, particularly in understanding the CRISPR-Cas mechanism. This has led to various CRISPR-Cas variants, including CRISPR-Cas13, CRISPR interference, CRISPR activation, base editors, primes editors, and CRASPASE, a new CRISPR-Cas system for genetic engineering that cleaves proteins. Moreover, gene editing technologies like the prime editor and base editor approaches offer excellent opportunities for plant genome engineering. These cutting-edge tools have opened up new avenues for rapidly manipulating plant genomes. This review article provides a comprehensive overview of the current state of plant genetic engineering, focusing on recently developed tools for gene alteration and their potential applications in plant research.

Table S2. Mean senescence (visual injury) measured across two years (2016 and 2017). (XLSX 17Â kb)

The Earth’s terrestrial carbon stocks have depleted an estimated 344 billion tons. Carbon losses amid water scarcity in climate-vulnerable drylands are a mounting challenge, and their restoration requires optimizing water-to-carbon biotransformation. Synthesizing thousands of worldwide experimental studies, we identify key biophysical pathways for enhancing carbon restoration and ecosystem resilience in global drylands, as follows: (i) Cropping diversification increases net primary productivity by 18.9% (n = 1296 studies); (ii) Regulated deficit irrigation cuts water use by 30–50% while improving yield-scaled water use efficiency by 3.4% (n = 9068 paired comparisons); (iii) Soil mulching increases land productivity by 22.2% (n = 48,144 paired comparisons); and (iv) Soil health rejuvenation strategies can sequester 1.2–3.8 t SOC ha⁻¹ yr⁻¹. Priorities to implement these biophysical pathways to enhance water-to-carbon biotransformation include: ‘smart’ irrigation, carbon dioxide fertilization-enhanced photosynthetic assimilation, rhizosphere engineering for microbiome-based nutrient solutions, biodegradable mulches replacing traditional polyethylene films, diversifying farming systems with low soil disturbance and climate-smart practices, and inclusive governance frameworks. These prioritized strategies reconcile water scarcity with carbon restoration to enhance dryland ecosystem resilience, which supports the UN’s Sustainable Development Goals. Crop diversification, regulated deficit irrigation, soil mulching, and soil health restoration can optimize water-to-carbon biotransformation in global drylands, according to a meta-analysis study.

Climate change threatens global food and nutritional security through negative effects on crop growth and agricultural productivity. Many countries have adopted ambitious climate change mitigation and adaptation targets that will exacerbate the problem, as they require significant changes in current agri-food systems. In this review, we provide a roadmap for improved crop production that encompasses the effective transfer of current knowledge into plant breeding and crop management strategies that will underpin sustainable agriculture intensification and climate resilience. We identify the main problem areas and highlight outstanding questions and potential solutions that can be applied to mitigate the impacts of climate change on crop growth and productivity. Although translation of scientific advances into crop production lags far behind current scientific knowledge and technology, we consider that a holistic approach, combining disciplines in collaborative efforts, can drive better connections between research, policy, and the needs of society.

It seems logical to talk about plants with an increased productivity for the fast increasing world population. Crop plant development showing tolerance to various abiotic stresses has got immense potential and seems a promising strategy that may help to satisfy population demands for nutritious food. Currently, plant biotechnology is responsible to develop environmental stress tolerance and higher-yielding crop plants with increased nutritional value. Even though plant growth and development are governed by a variety of genetic, biochemical, environmental, and molecular processes, photosynthesis is a complex mechanism responsible for providing the energy required for crop productivity. The successful improvement in photosynthetic efficiency of crops, especially the leading cereal crops, has substantially increased global food production even without increasing cultivation areas. However, the availability of high throughput tools and technologies such as dynamic and sophisticated genome editing techniques for improving cultivars will play a vital role, especially in increasing photosynthetic efficiency. This technique represents a promising strategy to tackle yield-related problems, such as improvement in photosynthetic efficiency and abiotic stress tolerance of plants and may serve as a foundation for the second green revolution in the future. This chapter aims to discuss recent advances, current challenges, and future perspectives for targeting improved photosynthesis for enhanced and sustainable food, fiber, and fuel production under different environmental stresses.