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Societal Impact Statement: Preserving and conserving crop landraces, tended by indigenous farming communities, is crucial for future food security. This research focused on rice landrace diversity in the north‐eastern Himalayan region of Nagaland, India, where Naga communities cultivate rice according to their dietary and cultural preferences. Rice diversity is closely linked to the region's ethnolinguistic and ecological variety. On‐farm conservation, in collaboration with indigenous communities, is imperative to protect these germplasm resources. Involving these communities actively in conservation efforts will safeguard their traditional knowledge, endorse sustainable farming practices, and enhance the resilience of local agricultural systems. Summary: Understanding the genetic diversity and cultural significance of crop landraces is crucial for their conservation and sustainable utilization. This study focused on rice landraces from Nagaland in north‐eastern India to assess their genetic diversity and explore their associations with ethnolinguistic groups.We collected 78 rice landraces from Nagaland and a small part of Manipur and conducted microsatellite genotyping for genetic analysis. We integrated social anthropology and population genetics analyses of rice landraces to glean insights into the genetic diversity, population structure, and ethnolinguistic history of rice cultivation in Nagaland.The study revealed the rich cultural significance of rice landraces among the Nagas. Farmers practiced small‐scale subsistence farming, maintaining diverse rice landraces. Naming conventions were based on factors such as seed source, color, grain type, and ecological suitability. Rice landraces played important roles in ethnic cultures, festivals, and religious ceremonies. Genetic analysis identified significant diversity, with 277 alleles across 69 loci and a moderate gene diversity of 0.57. Two distinct sub‐populations were identified, with one dominated by Chakhesang and Angami Nagas and the other by Sümi and Lotha accessions. Differentiation was observed between lowland and upland cultivars, with one sub‐population comprising exclusively lowland varieties. Cultural factors and cultivation practices influenced population differentiation, with ethnicity and ecotype having a significant impact. The study also highlighted the correlation between ethnolinguistic differentiation and the indica–japonica structuring of rice landraces. Different ethnic groups in Nagaland had distinct cultivation practices, contributing to genetic differentiation.Overall, this research emphasizes the need to preserve rice landraces and associated traditional knowledge for future improvements and cultural heritage conservation. It provides insights into genetic diversity, cultural significance, and the relationship between genetic diversity, cultural practices, and agricultural traditions. [ABSTRACT FROM AUTHOR]

Carotenoid metabolism is regulated by several genes encoding carotenoid biosynthetic pathway enzymes. In the present study, a fruit transcriptome in tomato ( Solanum lycopersicum) was compared between high lycopene accumulating genotype EC-521086 and low lycopene accumulating genotype VRT-32-1 at three different stages (green, breaker and red) of fruit ripening. This analysis led to the identification of 2,558 differentially expressed genes at three stages of fruit ripening. Among these genes, 123 were carotenoid-correlated genes. Quantitative RT-PCR analysis revealed high expression of genes encoding enzymes involved in lycopene biosynthesis like IPP isomerase, phytoene synthase, phytoene desaturase, z-carotene desaturase; and comparatively lower expression of genes encoding enzymes involved in lycopene catabolism like lycopene cyclase, carotenoid e-ring hydroxylase, zeaxanthin epoxidase, violaxanthin de-epoxidase and neoxanthin synthase in EC-521086, thereby possibly explaining the high lycopene content in EC-521086 as compared with the low lycopene genotype VRT-32-1. Further, the EC-521086 genotype exhibited high expression of the TOMATO AGAMOUS-LIKE 1 ( TAGL1) MADS box gene—a positive regulator of lycopene accumulation—at breaker stage, and low expression of the ethylene receptor LeETR4 gene—a negative regulator of trans-lycopene and β-carotene accumulation, at the red stage of fruit ripening. Our results clearly demonstrate the role of specific genes in accumulation of high lycopene in the EC-521086 tomato genotype during the fruit ripening processes. [ABSTRACT FROM AUTHOR]

Identification of genes that are coexpressed across various tissues and environmental stresses is biologically interesting, since they may play coordinated role in similar biological processes. Genes with correlated expression patterns can be best identified by using coexpression network analysis of transcriptome data. In the present study, we analyzed the temporal-spatial coordination of gene expression in root, leaf and panicle of rice under drought stress and constructed network using WGCNA and Cytoscape. Total of 2199 differentially expressed genes (DEGs) were identified in at least three or more tissues, wherein 88 genes have coordinated expression profile among all the six tissues under drought stress. These 88 highly coordinated genes were further subjected to module identification in the coexpression network. Based on chief topological properties we identified 18 hub genes such as ABC transporter, ATP-binding protein, dehydrin, protein phosphatase 2C, LTPL153 - Protease inhibitor, phosphatidylethanolaminebinding protein, lactose permease-related, NADP-dependent malic enzyme, etc. Motif enrichment analysis showed the presence of ABRE cis-elements in the promoters of > 62% of the coordinately expressed genes. Our results suggest that drought stress mediated upregulated gene expression was coordinated through an ABA-dependent signaling pathway across tissues, at least for the subset of genes identified in this study, while down regulation appears to be regulated by tissue specific pathways in rice.