Soybean, which has many foods, feed, and industrial raw material products, has relatively limited genetic diversity due to the domestication practices which mainly focused on higher yield for many centuries. Besides, cleistogamy in soybean plant reduces genetic variations even further. Improving genetic variation in soybean is crucial for breeding applications to improve traits such as higher yield, early maturity, herbicide, and pest resistance, lodging and shattering resistance, seed quality and composition, abiotic stress tolerance and more. In the 21st century, there are numerous alternatives from conventional breeding to biotechnological approaches. Among these, mutation breeding is still a major method to produce new alleles and desired traits within the crop genomes. Physical and chemical mutagen protocols are still improving and mutation breeding proves its value to be fast, flexible, and viable in crop sciences. In the verge of revolutionary genome editing era, induced mutagenesis passed important cross-roads successfully with the help of emerging supportive NGS based-methods and non-destructive screening approaches that reduce the time-consuming labor-intensive selection practices of mutation breeding. Induced mutagenesis will retain its place in crop science in the next decades, especially for plants such as soybean for which cross breeding is limited or not applicable.

The number of approaches related to recombinant protein production in plants is increasing rapidly day by day. Plant-based expression offers a safe, cost-effective, scalable, and potentially limitless way to rapidly produce recombinant proteins. Plant systems, which have significant advantages over animal and yeast recombinant protein production systems, are particularly promising for the large-scale production of antibodies and therapeutic proteins. Molecular pharming with transgenic plant systems become prominent among other production systems with its low cost, absence of human or animal pathogen contaminants, and the ability to use post-translational modifications such as glycosylation. The ability to produce recombinant pharmaceutical proteins in plant seeds, plant cells and various plant tissues such as hairy roots and leaves, through the stable transformation of the nuclear genome or transient expression, allows for the establishment of different production strategies. In particular, the rapid production of candidate proteins by transient expression, which eliminates the need for lengthy transformation and regeneration procedures, has made plants an attractive bioreactor for the production of pharmaceutical components. This chapter aimsto exhibit the current plant biotechnology applications and transgenic strategies used for the production of recombinant antibodies, antigens, therapeutic proteins and enzymes, which are used especially in the treatment of various diseases.

Humankind interfered in the natural selection of plants in favor of traits such as yield, grain quality, productivity, and flavor principally at the expense of several biotic and abiotic stress tolerance capacities. Plants are subjected to the detrimental effects of the combination of these factors due to their stationary nature. Today, there are various breeding approaches from classical to transgenesis and even genome editing to tame plant genome for our purposes. Additionally, the significance of epigenetic regulation in response to biotic and abiotic stresses has been recognized in the last decade. Acquisition and preservation of stress memory for the progeny to allow them to adapt to similar conditions through methylation, histone modification, and chromatin structure alterations are the focus of attention. Enlightening the cross talk between these components of acquired transgenerational memory may aid to breed more efficient and environmentally friendly crops in current agricultural systems. Priming applications have been extensively studied to induce stress memory of the plant by external stimulus as a warning signal, which may ignite minor activations of stress-responsive gene expression and eventually turn into strong resistance. The present chapter will discuss the basis and the recent advances in plant epigenetic regulation with emphasis on chemical, biotic, and abiotic priming agents.

The bread wheat cultivar (Triticum aestivum L. cv. Sagittario) as a parental line and its mutant, drought-tolerant lines (Mutant lines 4 and 5) were subjected to polyethylene glycol (PEG)-induced drought. Drought stress resulted in decreased chlorophyll levels and the accumulation of proline and TBARS, despite increases in activities of catalase, peroxidase, and superoxide dismutase enzymes. Transcription of the genes encoding these enzymes and delta-1-pyrroline 5-carboxylase synthetase was induced by drought. 2-DE gel electrophoresis analysis identified differentially expressed proteins (DEPs) in the mutant lines, which are distinguished by “chloroplast”, “mitochondrion”, “pyruvate dehydrogenase complex”, and “homeostatic process” terms. The drought tolerance of the mutant lines might be attributed to improved photosynthesis, efficient ATP synthesis, and modified antioxidant capacity. In addition to proteomics data, the drought tolerance of wheat genotypes might also be assessed by chlorophyll content and TaPOX gene expression. To our knowledge, this is the first proteomic analysis of gamma-induced mutants of bread wheat. These findings are expected to be utilized in plant breeding studies.

Soybean (Glycine max L.) is an important agricultural crop for human food and animal feed. Soybean yield is severely constrained by abiotic stresses such as salinity and drought, which affect large proportions of arable and irrigated lands worldwide. This necessitates the development of new soybean varieties tolerant to these stress factors. Mutation breeding is an effective approach to improve the stress tolerance of plants due to increased genetic diversity. In this study, two gamma-induced salinity and drought-tolerant soybean mutants (SM1 and SM3-1) were compared with the parental line S04-05 using GO and KEGG pathway enrichment analyses. GO enrichment analyses revealed extensive differential gene expression in the mutant lines under stress conditions, with significant enrichment of pathways related to photosynthesis, hormone signaling, carbohydrate metabolism, and flavonoid and isoflavonoid biosynthesis. Genotype-specific analyses indicated that the SM3-1 mutant exhibited a dynamic regulatory response associated with maintaining the photosynthetic apparatus and chloroplast homeostasis under stress, whereas the SM1 mutant showed an adaptation strategy based on metabolite-mediated osmotic adjustment and ROS scavenging. Compared to the parental variety S04-05, the mutants showed distinct metabolic regulation in phenylpropanoid/isoflavone metabolism, with upregulation of many isoflavone biosynthesis genes under salinity, drought, and untreated conditions, indicating a key and sustained role of this pathway in stress tolerance. Most SNPs identified in the isoflavone biosynthesis pathway consist of moderate-impact and modifier variations. These findings suggest that gamma mutagenesis and subsequent selection processes allow for the development of novel genetic variants that operate through different physiological and metabolic mechanisms but exhibit similar levels of tolerance. In this respect, the study reveals that mutation breeding is a potentially sustainable and effective breeding strategy for increasing abiotic stress tolerance in soybeans.

All life forms, from the simplest to the most complicated, are inevitably exposed to altering environmental conditions in their natural habitats, gradually depending on their lifestyle. Unfavorable alterations drive these life forms either to avoidance or defense as a response. Most of the essential plant growth-promoting environmental factors can also turn out to be stress factors. Water as the most abundant molecule of all living cells can cause stress either in deficit as drought or in excess as waterlogging. Temperature is important for the maintenance of all biomolecules and metabolic reactions; hence, both low and high temperatures are deleterious stress factors. Even though the plants were exposed to various volcanic origin, heavy metals and pollutants and evolved molecular mechanisms during millions year of evolution, rapid urbanization, and industrial progress introduce brand new pollutants as micro- and nanoplastics as well as nanoparticles to plants like never before. This chapter defines and evaluates major environmental abiotic stress factors with an emphasis on the latest knowledge of molecular effects on plants. In addition, novel stress factors, such as nanoparticles and microplastics, are looked over as hot prospects for the future of plant abiotic stress areas.