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Salinity represents a fatal factor affecting the productivity of alfalfa. But the regulation of salinity tolerance via lncRNAs and mRNAs remains largely unclear within alfalfa. For evaluating salinity stress resistance-related lncRNAs and mRNAs within alfalfa, we analyzed root transcriptomics in two alfalfa varieties, GN5 (salinity-tolerant) and GN3 (salinity-sensitive), after treatments with NaCl at 0 and 150 mM. There were altogether 117,677 lncRNAs and 172,986 mRNAs detected, including 1,466 lncRNAs and 2,288 mRNAs with significant differential expression in GN5150/GN50, GN3150/GN30, GN50/GN30, and GN5150/GN3150. As revealed by GO as well as KEGG enrichment, some ionic and osmotic stress-associated genes, such as HPCA1-LRR, PP2C60, PP2C71, CRK1, APX3, HXK2, BAG6, and ARF1, had up-regulated levels in GN5 compared with in GN3. In addition, NaCl treatment markedly decreased CNGC1 expression in GN5. According to co-expressed network analyses, six lncRNAs (TCONS_00113549, TCONS_00399794, TCONS_00297228, TCONS_00004647, TCONS_00033214 and TCONS_00285177) modulated 66 genes including ARF1, BAG6, PP2C71, and CNGC1 in alfalfa roots, suggesting that these nine genes and six lncRNAs probably facilitated the different salinity resistance in GN5 vs. GN3. These results shed more lights on molecular mechanisms underlying genotype difference in salinity tolerance among alfalfas. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of water deficit on cadmium (Cd) accumulation in peanut plants during different developmental stages. Two contrasting peanut cultivars, Fenghua 1 (high-biomass cultivar) and Silihong (low-biomass cultivar), were grown in a Cd-contaminated arable soil under different water regimes. The two cultivars differed from each other in seed Cd concentrations. Fenghua 1 exhibited lower Cd concentrations in the seeds than Silihong, which is associated with root-to-shoot Cd translocation. Drought plays different roles in the translocation and redistribution of Cd in peanut plants during different developmental stages. At the seedling stage, drought decreased shoot Cd concentrations for both cultivars, whereas at the pod-filling and pod-ripened stages, drought increased shoot Cd concentrations. Similarly, drought stress reduced pod Cd concentrations at the pod-filling stages and increased at the pod-ripened stages. Seed Cd concentrations in mature plants were increased by drought for both cultivars. Seed Cd concentrations were negatively correlated with biomasses of shoots and pods, but positively correlated with Cd concentration in the shoots and pods. Increased seed Cd concentrations under drought stress might result from the concentration effects due to drought induced decrease of plant growth. [ABSTRACT FROM AUTHOR]

This study aims to investigate whether root system morphology is involved in the interspecific variations in Cd accumulation in herbaceous plants. Biomasses, root morphology, and Cd accumulation of 18 herbaceous species were determined under 0, 2, and 10 mg kg Cd conditions. Significant variations were found in biomass production, root system morphology, and Cd accumulation among the 18 species. Cd concentrations in the shoot had negative correlations with the biomass of roots and shoots in the 2 mg kg Cd treatment. Total amounts of Cd in plants showed positive correlations with the biomass of roots and shoots, total root lengths, root surface areas, root volumes, and proportions of the fine roots (diameter <0.2 mm). Percentages of Cd in shoots were positively related to specific root lengths, root surface areas, and plant biomasses but negatively correlated with proportions of roots in the 0.6-0.8-mm diameter class. High-biomass species (rapeseed, Indian mustard, and four-o'clock) have high Cd uptake capacity due to their large root system. Longer and thinner roots might contribute to higher capacity for transferring Cd from roots to shoots, while coarse roots (i.e., diameter of 0.6-0.8 mm) could retain more Cd in the tissues and, consequently, reduce Cd transfer from roots to shoots. [ABSTRACT FROM AUTHOR]

Background: Radish (Raphanus sativus L.), is an important root vegetable crop worldwide. Glucosinolates in the fleshy taproot significantly affect the flavor and nutritional quality of radish. However, little is known about the molecular mechanisms underlying glucosinolate metabolism in radish taproots. The limited availability of radish genomic information has greatly hindered functional genomic analysis and molecular breeding in radish., Results: In this study, a high-throughput, large-scale RNA sequencing technology was employed to characterize the de novo transcriptome of radish roots at different stages of development. Approximately 66.11 million paired-end reads representing 73,084 unigenes with a N50 length of 1,095 bp, and a total length of 55.73 Mb were obtained. Comparison with the publicly available protein database indicates that a total of 67,305 (about 92.09% of the assembled unigenes) unigenes exhibit similarity (e -value ≤ 1.0e⁻⁵) to known proteins. The functional annotation and classification including Gene Ontology (GO), Clusters of Orthologous Group (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the main activated genes in radish taproots are predominantly involved in basic physiological and metabolic processes, biosynthesis of secondary metabolite pathways, signal transduction mechanisms and other cellular components and molecular function related terms. The majority of the genes encoding enzymes involved in glucosinolate (GS) metabolism and regulation pathways were identified in the unigene dataset by targeted searches of their annotations. A number of candidate radish genes in the glucosinolate metabolism related pathways were also discovered, from which, eight genes were validated by T-A cloning and sequencing while four were validated by quantitative RT-PCR expression profiling., Conclusions: The ensuing transcriptome dataset provides a comprehensive sequence resource for molecular genetics research in radish. It will serve as an important public information platform to further understanding of the molecular mechanisms involved in biosynthesis and metabolism of the related nutritional and flavor components during taproot formation in radish.