Search Results (5)

Caragana intermedia is a perennial shrub species in the genus Caragana (Fabaceae), demonstrating remarkable stress resistance and adaptability. However, research on its somatic embryogenesis (SE) and genetic transformation techniques remains limited. In this study, we established an SE system by utilizing immature cotyledons isolated from young C. intermedia seeds. Our findings demonstrated that the immature cotyledons at 6–7 weeks after flowering (WAF) were the best explants for SE. The optimal embryo induction medium consisted of an MS basal medium supplemented with 5 mg/L α-naphthaleneacetic acid (NAA), 3 mg/L 6-benzylaminopurine (6-BA), 30 g/L sucrose, 7 g/L agar, and 500 mg/L hydrolyzed casein. Cotyledon-stage embryos germinated on a half-strength MS medium, exhibiting a 34.36% germination rate. Based on the SE system, we developed a preliminary genetic transformation system using the RUBY reporter gene, which successfully generated transgenic calli and cotyledon-stage embryos. The establishment of the SE system is expected to shorten breeding cycles, facilitate propagation of superior cultivars, and support large-scale industrial applications in C. intermedia. Furthermore, the stable transformation system provides a platform for molecular breeding and gene function verification. Full article

Elucidating the impact of rhizosphere microbial communities in the Caragana intermedia forest on soil polyfunctionality can significantly enhance our understanding of the microbial mechanisms underpinning soil multi-functionality, which is crucial for sustainable land management. The rhizosphere soils under Caragana intermedia forests in different regions with variable precipitation gradients (MAP500 (precipitation ≥ 500 mm), MAP450 (400~500 mm), MAP300 (300~400 mm), MAP250 (200~300 mm)) were investigated in the research object. The interrelationships among soil properties, particularly the soil bacterial taxa and soil multi-functionality, were examined using metagenomic analysis, sequencing techniques, redundancy analysis, and partial least squares path modeling. The results show that (1) concurrent with escalating precipitation, Rhizosphere Soil Multi-functionality Index (SMI) exhibited a significant increase (p < 0.05); (2) the community structures of the Always Abundant Taxa (AAT), Always Rare Taxa (ART), Moderate Taxa (MT), Conditionally Abundant Taxa (CAT), Conditionally Rare group (CRT), and Conditionally Abundant Taxa (CRAT) varied significantly across precipitation gradients. Mean annual precipitation (MAP), soil moisture content (SMC), and pH were identified as the most critical environmental factors influencing the overall bacterial community and various taxa; (3) precipitation predominantly exerts indirect effects on AAT, MT, CAT, and CRAT by modulating soil moisture. Bacterial taxa that are conditionally rare or abundant in arid and semi-arid regions are the principal drivers of soil multi-functionality alterations within the rhizosphere of the Caragana intermedia forest. In the stewardship of Caragana intermedia plantations, microbial community composition can be optimized through the regulation of soil moisture and pH, as well as the strategic introduction of conditional microbial taxa, thereby enhancing the plantation’s resilience to climate change. This research contributes to sustainable land use practices by providing insights into microbial management strategies that enhance soil health and ecosystem resilience. Full article

This study was carried out to clarify the response of photosynthesis physiology of Caragana intermedia, an excellent tree species for wind protection and sand fixation, to soil water content (SWC) and to determine the relevant threshold ranges in the sandy lands of Qinghai-Tibet Plateau. In this study, based on the three-year forest experiment from 2017a to 2019a, C. intermedia in different afforestation years (2013a, 2011a, 2008a, 2006a, 2001a and 1986a) were selected for experimental analysis, the response process of leaf photosynthesis of C. intermedia to SWC changes was studied, and the physiological mechanism and growth suitability of C. intermedia to adapt to an alpine desert environment were clarified. The results showed that SWC played a critical role in the photosynthesis of C. intermedia in the sandy lands of Qinghai-Tibet Plateau. Afforestation years are negatively correlated with Pn, gs and Tr, but positively correlated with WUE; the longer the afforestation years, the higher demand for soil moisture. Regarding the relative roles of SWC and photosynthetic parameters, we demonstrated that this showed a significant square relationship (p < 0.001), while stomatal closure induced by the photosynthesis decline was important under dryness stress. The no-productivity and no-efficiency water (NPNEW) for the photosynthesis physiology of trees in different afforestation years were 3.31–3.64%; 3.33–4.06%; 3.08–3.63%; 3.36–3.85%; 1.45–4.02% and 3.39–5.50%, and the highest productivity with the highest availability of water (HPHAW) were 6.65–7.19%; 6.74–7.36%; 7.36–7.91%; 6.10–7.51%; 6.57–8.19% and 6.52–8.35%. Plantations in different afforestation years could survive safely in the sandy lands of Qinghai-Tibet Plateau. However, the productivity of trees decreased with the increase length of afforestation years; thus, we should pay attention to their growth status and make timely management adjustments in the future. These results provide important information for theoretical support for the diagnosis of ecological adaptability and field water management of C. intermedia in the sandy lands of Qinghai-Tibet Plateau and provide a reference for the adaptability evaluation and water–carbon cycle simulation of plantations in the sandy lands of Qinghai-Tibet Plateau against the background of global climate change. Full article

Caragana intermedia, a leguminous shrub widely distributed in cold and arid regions, is rich in secondary metabolites and natural active substances, with high nutritional and medical values. It is interesting that the pods of C. intermedia often show different colors among individual plants. In this study, 10-, 20- and 30-day-old red and green pods of C. intermedia were used to identify and characterize important metabolites associated with pod color. A total 557 metabolites, which could be classified into 21 groups, were detected in the pod extracts using liquid chromatography coupled with ESI-triple quadrupole-linear ion trap mass spectrometer (LC-ESI-MS/MS). Metabolomics analysis revealed significant differences in 15 groups of metabolites between red and green pods, including amino acids, nucleotide derivatives, flavonoids, and phytohormones. Metabolic pathway analysis showed that the shikimic acid and the phytohormone metabolic pathways were extraordinarily active in red pods, and the difference between red and green pods was obvious. Moreover, red pods showed remarkable flavonoids, cytokinins, and auxin accumulation, and the content of total flavonoids and proanthocyanidins in 30-day-old red pods was significantly higher than that in green pods. This metabolic profile contributes to valuable insights into the metabolic regulation mechanism in different color pods. Full article

Carainterol A is a eudesmane sesquiterpenoid extracted from Caragana intermedia. We have reported that carainterol A showed potent glucose consumption activity in C₂C₁₂ muscle cells and the db/db mouse model. However, the mechanism of the hypoglycemic effect of carainterol A remains elusive. In this article, we present a network pharmacology approach to predict the target and signaling pathway of carainterol A which was subsequently validated in HepG2 cells. It was demonstrated that carainterol A could increase the protein levels of IRS-1 and the downstream protein kinase AKT phosphorylation at a low micromolar level. These findings suggest that carainterol A can be a valuable lead compound and a promising chemical probe for the insulin signaling pathway. Full article