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Chemical fertilizers can improve crop productivity, but irrational fertilization often results in low crop quality and yield, poor soil fertility, and severe environmental pollution. Nevertheless, little research has been conducted with a close focus on the cultivation of radish in high mountain regions, a widely cultivated root vegetable known for its nutritional value and economic importance. Here, a method of reducing chemical fertilizers combined with the application of organic fertilizers is proposed upon studying four different ratios of chemical and organic fertilizers, including control (375 kg·ha−1 chemical fertilizer + 4500 kg·ha−1 organic fertilizer) and combinations (T1: 12% reduction in chemical fertilizer + 4500 kg·ha−1 organic fertilizer; T2: 20% reduction in chemical fertilizer + 4500 kg·ha−1 organic fertilizer; T3: 28% reduction in chemical fertilizer + 4500 kg·ha−1 organic fertilizer). Their effects on radish quality, yield, and soil environment were investigated. Compared with the control group, T2 significantly increased radish yield by 12.92% and improved the contents of vitamin C, soluble sugars, sulforaphane soluble solids, and titratable acidity in the radish roots by 10.62%, 2.15%, 50.00%, 26.90%, and 43.90%, respectively. The soil nutrient content was increased by the T2 treatment, with a 7.69% and 14.29% increase in total nitrogen and total phosphorus content, respectively, compared with the control. Moreover, soil urease activity, sucrase activity, alkaline phosphatase activity, and catalase activity were significantly enhanced by the T2 treatment, showing an improvement of 11.13%, 44.30%, 26.41%, and 9.33% compared with the control, respectively (p < 0.05). The relative abundance of beneficial bacterial phyla such as Proteobacteria and Actinobacteria was increased in the T2 treatment, potentially helping to maintain better soil health and long-term fertility. In summary, a promising fertilizer management strategy is herein unveiled through the reduction of chemical fertilizers and the application of organic fertilizer that not only improves radish yield and quality but also optimizes the soil environment, providing an effective means for sustainable crop production. [ABSTRACT FROM AUTHOR]

Despite a range of initiatives to reduce global carbon emission, the mean global temperature is increasing due to climate change. Since rising temperatures pose a serious threat of food insecurity, it is important to further explore important biological molecules that can confer thermotolerance to plants. Recently, melatonin has emerged as a universal abiotic stress regulator that can enhance plant tolerance to high temperature. Nonetheless, such regulatory roles of melatonin were unraveled mainly by assessing the effect of exogenous melatonin on plant tolerance to abiotic stress. Here, we generated melatonin deficient tomato plants by silencing of a melatonin biosynthetic gene, CAFFEIC ACID O-METHYLTRANSFERASE 1 (COMT1), to unveil the role of endogenous melatonin in photosynthesis under heat stress. We examined photosynthetic pigment content, leaf gas exchange, and a range of chlorophyll fluorescence parameters. The results showed that silencing of COMT1 aggravated heat stress by inhibiting both the light reactions and the carbon fixation reactions of photosynthesis. The photosynthetic pigment content, light absorption flux, trapped energy flux, energy dissipation, density of active reaction center per photosystem II (PSII) cross-section, the photosynthetic electron transport rate, the maximum photochemical efficiency of PSII photochemistry, and the rate of CO2 assimilation all decreased in COMT1-silenced plants compared with that of non-silenced plants particularly under heat stress. However, exogenous melatonin alleviated heat-induced photosynthetic inhibition in both genotypes, indicating that melatonin is essential for maintaining photosynthetic capacity under stressful conditions. These findings provide genetic evidence on the vital role of melatonin in photosynthesis and thus may have useful implication in horticultural crop management in the face of climate change. [ABSTRACT FROM AUTHOR]

Background: Cisplatin (DDP) based combination chemotherapy is a vital method for the treatment of bladder cancer (BLca). Chemoresistance easily occurs in the course of cisplatin chemotherapy, which is one of the important reasons for the unfavorable prognosis of BLca patients. Circular RNAs (circRNAs) are widely recognized for their role in the development and advancement of BLca. Nevertheless, the precise role of circRNAs in DDP resistance for BLca remains unclear. Methods: To study the properties of circATIC, sanger sequencing, agarose gel electrophoresis and treatment with RNase R/Actinomycin D were utilized. RT-qPCR assay was utilized to assess the expression levels of circRNA, miRNA and mRNA in BLca tissues and cells. Functional experiments were conducted to assess the function of circATIC in BLca progression and chemosensitivity in vitro . Various techniques such as FISH, Dual-luciferase reporter assay, TRAP, RNA digestion assay, RIP and ChIRP assay were used to investigate the relationships between PTBP1, circATIC, miR-1247-5p and RCC2. Orthotopic bladder cancer model, xenograft subcutaneous tumor model and xenograft lung metastasis tumor model were performed to indicate the function and mechanism of circATIC in BLca progression and chemosensitivity in vivo . Results: In our study, we observed that circATIC expression was significantly enhanced in BLca tissues and cells and DDP resistant cells. Patients with higher circATIC expression have larger tumor diameter, higher incidence of postoperative metastasis and lower overall survival rate. Further experiments showed that circATIC accelerated BLca cell growth and metastasis and induced DDP resistance. Mechanistically, alternative splicing enzyme PTBP1 mediated the synthesis of circATIC. circATIC could enhance RCC2 mRNA stability via sponging miR-1247-5p or constructing a circATIC/LIN28A/RCC2 RNA-protein ternary complex. Finally, circATIC promotes RCC2 expression to enhance Epithelial-Mesenchymal Transition (EMT) progression and activate JNK signal pathway, thus strengthening DDP resistance in BLca cells. Conclusion: Our study demonstrated that circATIC promoted BLca progression and DDP resistance, and could serve as a potential target for BLca treatment., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Rising atmospheric carbon dioxide, an important driver of climate change, has multifarious effects on crop yields and quality. Despite tremendous progress in understanding the mechanisms of plant responses to elevated CO 2 , only a few studies have examined the CO 2 -enrichment effects on tea plants. Tea [ Camellia sinensis (L.)], a non-deciduous woody perennial plant, operates massive physiologic, metabolic and transcriptional reprogramming to adapt to increasing CO 2 . Tea leaves elevate photosynthesis when grown at CO 2 -enriched environment which is attributed to increased maximum carboxylation rate of RuBisCO and maximum rates of RuBP regeneration. Elevated CO 2 -induced photosynthesis enhances the energy demand which triggers respiration. Stimulation of photosynthesis and respiration by elevated CO 2 promotes biomass production. Moreover, elevated CO 2 increases total carbon content, but it decreases total nitrogen content, leading to an increased ratio of carbon to nitrogen in tea leaves. Elevated CO 2 alters the tea quality by differentially influencing the concentrations and biosynthetic gene expression of tea polyphenols, free amino acids, catechins, theanine, and caffeine. Signaling molecules salicylic acid and nitric oxide function in a hierarchy to mediate the elevated CO 2 -induced flavonoid biosynthesis in tea leaves. Despite enhanced synthesis of defense compounds, tea plant defense to some insects and pathogens is compromised under elevated CO 2 . Here we review the physiological and metabolic responses of tea plants to elevated CO 2 . In addition, the potential impacts of elevated CO 2 on tea yield and defense responses are discussed. We also show research gaps and critical research areas relating to elevated CO 2 and tea quality for future study., (Copyright © 2020 Ahammed, Li, Liu and Chen.)