Development & formation of several plant organs and regulating processes, including morphogenesis, signal transduction, and floral meristem determinacy, are regulated by the SRS (SHI -related sequence) transcription factor family. However, the functional contributions of SRS family genes in Arabidopsis related to phenology, hormone-mediated regulation, and abiotic stress adaptation have not been comprehensively elucidated. The objective of this study is to comprehensively investigate the SRS gene family in the Arabidopsis genome and to clarify their prospective functional roles in mediating responses to diverse hormonal signals and abiotic stress conditions. Comprehensive analyses were performed using multiple databases and bioinformatics platforms to assess chromosomal positioning, gene organization, conserved motifs & domains, structural homology, cis -acting regulatory elements, evolutionary relationships, duplication events, transcriptional expression patterns, and potential protein interaction networks. Through phylogenetic analysis, along with conserved domain (DUF702 and IGGH) and motif characterization, ten identified SRS genes in Arabidopsis were classified into two distinct groups: Group I (eight members) and Group II (two members). The results demonstrated that all the Arabidopsis chromosomes contain AtSRS genes and comprise 74 distinct cis acting regulatory elements in their distinct promoter regions, which facilitates a wide range of tissue expression patterns in response to various hormonal activities and abiotic stressors. Based on phylogenetic analysis, some AtSRS genes appear to have undergone functional diversification, while others may function similarly to their orthologs in other plant species. This study reveals the door to the determination of AtSRS gene-specific functions and the clarification of the mechanisms via which SRS genes regulate hormones, stress responses, floral formation and development, and lateral root formation.

The E2F family gene is one of the most important G ₁ –S checkpoint regulatory transcription factors to monitor and regulate the accurate DNA replication and progression of the cell cycle in eukaryotes. Expression of this gene in multiple environmental factors has been reported in diversified plant species. However, characterization and investigation of the putative influential role of this family gene in Brassica species were not reported. In addition to expression profiling and mRNA target analysis, we have comprehensively identified and characterized 14 Br E2F/DP transcription factors from the data in available databases of Brassica rapa and compared them with five other species. Six pairs of segmentally duplicated BrE2F/DP paralogous genes were identified in this study, with Ka/Ks values of < 1.0. The findings indicated their evolution through segmental duplication across the chromosome after the Brassica splits from Arabidopsis and functional similarities with Brassica oleracea proteins. Most of the stress‐responsive microRNA (miRNA) targeted BrE2F/DP5 , BrE2F/DP12 , BrE2F/DP1, and BrE2F/DP8. Cis‐element composition and diversified functional expressions indicated their involvement in biological pathways for adaptation under multiple stress resistances, including cell cycle progression during growth and development. The findings provided comprehensive information on the multifunctional roles of the E2F/DP family in Brassica spp., importantly, biotic and abiotic stress resistance.

Tomato (Solanum lycopersicum L.) is one of the most commonly cultivated and economically important vegetable crops. However, tomato production is severely impacted by various abiotic stresses, including drought, salinity, heat, cold, and oxidative stress. These stresses disrupt critical physiological processes, reducing yield and fruit quality. This chapter provides a comprehensive overview of the impacts of abiotic stress on tomato growth, yield, and quality, focusing on the molecular and physiological mechanisms that tomato plants employ to cope with these challenges. The chapter also addresses the latest developments in breeding strategies toward improving abiotic stress tolerance in tomato, including conventional techniques, marker-assisted selection, genome-wide association study, and CRISPR/Cas9 technology-based gene editing. Additionally, it describes the introduction of novel omics technologies, including transcriptomics, proteomics, metabolomics, and ionomics, providing a deeper understanding of the molecular basis of stress tolerance response in tomatoes. These new technologies are revolutionizing tomato breeding and making it possible to develop varieties that are more tolerant to various types of stress. Despite the progress made, challenges remain in improving the efficiency and adaptability of these technologies. This chapter concludes by emphasizing the importance of a multi-faceted approach, combining genetic resources, biotechnological advancements, and sustainable breeding practices to ensure the development of climate-resilient tomato cultivars for global food security.

Maize is a cornerstone of global agriculture, essential for food security, livestock feed, and industrial uses. With the increasing demand for maize due to population growth and changing dietary patterns, there is a pressing need to enhance maize production. Hybridization is a strategic approach for developing high-yielding and stress-tolerant maize varieties and evaluating these hybrids in specific environmental conditions is vital for optimizing yield and adaptability. With this objective, a field experiment was conducted to evaluate the growth and yield performance of ten hybrid maize varieties under the local climatic conditions of Mymensingh. A randomized complete block design with three replicates was used to collect data on thirteen different parameters. Significant variation was observed among the hybrids for all phenological, growth, and yield contributing traits. The phenotypic coefficient of variation exceeds the genotypic coefficient of variation, indicating substantial environmental interactions. Heritability estimates ranged from 59% to 98%. Positive correlations were noted between cob length, cob diameter, grains per row, and 100-seed weight with kernel weight per plant. Path coefficient analysis revealed that plant height, cob diameter, number of leaves at harvest, cob length, and grains per row positively influenced grain yield. Among the hybrids, Kaveri54 exhibited superior performance with a kernel weight of 202.7 g. Therefore, Kaveri54 is recommended as a promising hybrid for maize cultivation in the Mymensingh region, which will support future breeding efforts aimed at improving yield and resilience.