A Simple Method Using an Allometric Model to Quantify the Carbon Sequestration Capacity in Vineyards.

Winegrapes are an important component of agroecosystems. They are endowed with great potential to sequester and store carbon to slow down greenhouse gas emissions. Herein, the biomass of grapevines was determined, and the carbon storage and distribution features of vineyard ecosystems were correspondingly analyzed using an allometric model of winegrape organs. Then, the carbon sequestration of Cabernet Sauvignon vineyard in the Helan Mountain East Region was quantified. It was found that the total carbon storage of grapevines increased with vine age. The amounts of the total carbon storage in the 5-year-old, 10-year-old, 15-year-old, and 20-year-old vineyards were 50.22 t·ha-1, 56.73 t·ha-1, 59.10 t·ha-1, and 61.06 t·ha-1, respectively. The soil held the majority of the carbon storage, which was concentrated in the top and subsurface layers (0-40 cm) of the soil. Moreover, the biomass carbon storage was mainly distributed in the perennial organs (perennial branches and roots). In young vines, carbon sequestration increased each year; however, the increased rate in carbon sequestration decreased with winegrape growth. The results indicated that vineyards have a net carbon sequestration capacity, and within certain years, the age of grapevines was found to be positively correlated with the amount of carbon sequestration. Overall, the present study provided accurate estimations of the biomass carbon storage in grapevines using the allometric model, which may help vineyards become recognized as important carbon sinks. Additionally, this research can also be used as a basis for figuring out the ecological value of vineyards on a regional scale.

Transcriptome profiling reveals potential genes involved in browning of fresh-cut eggplant (Solanum melongena L.).

Fresh-cut processing promotes enzymatic browning of fresh fruits and vegetables, which negatively affects the product appearance and impacts their nutrition. We used RNA-sequencing to analyze the transcriptomic changes occurring during the browning of fresh-cut eggplant fruit samples from both browning-sensitive and browning-resistant cultivars to investigate the molecular mechanisms involved in browning. A total of 8347 differentially expressed genes were identified, of which 62 genes were from six gene families (i.e., PPO, PAL, POD, CAT, APX, and GST) potentially associated with enzymatic browning. Furthermore, using qRT-PCR, we verified 231 differentially regulated transcription factors in fresh-cut eggplant fruits. The enzyme activities of PPO, POD, PAL, and CAT in '36' were significantly higher than those of 'F' fresh-cut for 15 min. Both PPO and POD play a major role in the browning of eggplant pulp and might therefore act synergistically in the browning process. Meanwhile, qPCR results of 18 browning related genes randomly screened in 15 eggplant materials with different browning tolerance showed variant-specific expression of genes. Lastly, gene regulatory networks were constructed to identify the browning-related genes. This work provides a basis for future molecular studies of eggplants, and lays a theoretical foundation for the development of browning-resistant fresh-cut fruits and vegetables.

Study on browning mechanism of fresh-cut eggplant (Solanum melongena L.) based on metabolomics, enzymatic assays and gene expression.

Enzymatic browning is one of the crucial problems compromising the flavor and texture of fresh-cut fruit and vegetables. In this study, an untargeted metabolomics approach based on liquid chromatography-mass spectrometry (LC-MS) was used to explore the browning mechanism in fresh-cut eggplant. Metabolomics studies showed that with the increase of fresh-cut time, the contents of 946 metabolites changed dynamically. The metabolites having the same trend share common metabolic pathways. As an important browning substrate, the content of chlorogenic acid increased significantly, suggesting that may be more important to fresh-cut eggplant browning; all 119 common differential metabolites in 5 min/CK and 3 min/CK contrastive groups were mapped onto 31 KEGG pathways including phenylpropanol metabolism, glutathione metabolism pathway, et al. In physiological experiments, results showed that the Phenylpropanoid-Metabolism-Related enzymes (PAL, C4H, 4CL) were changed after fresh-cut treatment, the activities of three enzymes increased first and then decreased, and reached the maximum value at 5 min, indicating the accumulation of phenolic substances. At the same time, ROS were accumulated when plant tissue damaged by cutting, the activities of related antioxidant enzymes (SOD, APX and CAT) changed dynamically after oxidative damage. SOD and APX content increased significantly and reached the maximum value at 10 min after cutting, and then showed a downward trend. However, CAT activity increased sharply and reached the maximum value within 3 min after cutting, then maintained the same activity, and showed a downward trend after 30 min. These data fully demonstrated that the activities of browning related enzymes and gene expression increased with the prolonging of fresh cutting time. We explained the browning mechanism of fresh-cut eggplant by combining metabolomics and physiology, which may lay the foundation for better understanding the mechanism of browning during the fruits and vegetables during processing.

Transcriptome profiling and gene expression analyses of eggplant (Solanum melongena L.) under heat stress.

Global warming induces heat stress in eggplant, seriously affecting its quality and yield. The response to heat stress is a complex regulatory process; however, the exact mechanism in eggplant is unknown. We analyzed the transcriptome of eggplant under different high-temperature treatments using RNA-Seq technology. Three libraries treated at high temperatures were generated and sequenced. There were 40,733,667, 40,833,852, and 40,301,285 clean reads with 83.98%, 79.69%, and 84.42% of sequences mapped to the eggplant reference genome in groups exposed to 28°C (CK), 38°C (T38), and 43°C (T43), respectively. There were 3,067 and 1,456 DEGs in T38 vs CK and T43 vs CK groups, respectively. In these two DEG groups, 315 and 342 genes were up- and down-regulated, respectively, in common. Differential expression patterns of DEGs in antioxidant enzyme systems, detoxication, phytohormones, and transcription factors under heat stress were investigated. We screened heat stress-related genes for further validation by qRT-PCR. Regulation mechanisms may differ under different temperature treatments, in which heat shock proteins and heat stress transcription factors play vital roles. These results provide insight into the molecular mechanisms of the heat stress response in eggplant and may be useful in crop breeding.

Chalcone synthase (CHS) family members analysis from eggplant (Solanum melongena L.) in the flavonoid biosynthetic pathway and expression patterns in response to heat stress.

Enzymes of the chalcone synthase (CHS) family participate in the synthesis of multiple secondary metabolites in plants, fungi and bacteria. CHS showed a significant correlation with the accumulation patterns of anthocyanin. The peel color, which is primarily determined by the content of anthocyanin, is an economically important trait for eggplants that is affected by heat stress. A total of 7 CHS (SmCHS1-7) putative genes were identified in a genome-wide analysis of eggplants (S. melongena L.). The SmCHS genes were distributed on 7 scaffolds and were classified into 3 clusters. Phylogenetic relationship analysis showed that 73 CHS genes from 7 Solanaceae species were classified into 10 groups. SmCHS5, SmCHS6 and SmCHS7 were continuously down-regulated under 38°C and 45°C treatment, while SmCHS4 was up-regulated under 38°C but showed little change at 45°C in peel. Expression profiles of key anthocyanin biosynthesis gene families showed that the PAL, 4CL and AN11 genes were primarily expressed in all five tissues. The CHI, F3H, F3'5'H, DFR, 3GT and bHLH1 genes were expressed in flower and peel. Under heat stress, the expression level of 52 key genes were reduced. In contrast, the expression patterns of eight key genes similar to SmCHS4 were up-regulated at a treatment of 38°C for 3 hour. Comparative analysis of putative CHS protein evolutionary relationships, cis-regulatory elements, and regulatory networks indicated that SmCHS gene family has a conserved gene structure and functional diversification. SmCHS showed two or more expression patterns, these results of this study may facilitate further research to understand the regulatory mechanism governing peel color in eggplants.

Transcriptome analysis revealed expression of genes related to anthocyanin biosynthesis in eggplant (Solanum melongena L.) under high-temperature stress.

BACKGROUND: Anthocyanin synthesis is affected by many factors, among which temperature is an important environmental factor. Eggplant is usually exposed to high temperatures during the cultivation season in Shanghai, China. Therefore,RNA -seq analysis was used to determine the effects of high-temperature stress on gene expression in the anthocyanin biosynthetic pathway of eggplant (Solanum melongena L.). RESULTS: We tested the heat-resistant cultivar 'Tewangda'. The plants were incubated at 38 °C and 45 °C, and the suitable temperature for eggplant growth was used as a control. The treatment times were 3 h and 6 h. The skin of the eggplant was taken for transcriptome sequencing, qRT-PCR assays and bioinformatic analysis. The results showed that 770 genes were differentially expressed between different treatments. Gene Ontology (GO) database and Kyoto Encyclopedia of Genes and Genomes (KEGG) database analyses identified 16 genes related to anthocyanin biosynthesis, among which CHSB was upregulated. Other genes, including BHLH62, MYB380, CHI3, CHI, CCOAOMT, AN3, ACT-2, HST, 5MA-T1, CYP75A2, ANT17, RT, PAL2, and anthocyanin 5-aromatic acyltransferase were downregulated. In addition, the Myb family transcription factor PHL11 was upregulated in the CK 3 h vs 45 °C 3 h, CK 3 h vs 38 °C 3 h, and CK 6 h vs 38 °C 6 h comparisons, and the transcription factor bHLH35 was upregulated in the CK 3 h vs 38 °C 3 h and CK 6 h vs 38 °C 6 h comparisons. CONCLUSION: These results indicated that high temperature will downregulate most of the genes in the anthocyanin biosynthetic pathway of eggplant. Our data have a reference value for the heat resistance mechanism of eggplant and can provide directions for molecular breeding of heat-resistant germplasm with anthocyanin content in eggplant.

Evaluation of surgical risk and prognosis between thyroid nodules of size <1 and ≥1 cm.

BACKGROUND: The objective of this study was to evaluate the surgical risk and prognosis between thyroid nodules of size <1 and ≥1 cm and to explore whether it is reasonable generally to ignore the diagnosis and treatment of thyroid nodules and thyroid carcinoma <1 cm in wide areas of China. METHODS: A retrospective observational study included all first-time thyroid surgery patients between January 2005 and December 2016 of the First Affiliated Hospital of Harbin Medical University. All patients were divided into two groups (group A: <1 cm, group B: ≥1 cm) according to the maximum diameter of the nodules and demographics, surgery procedure, pathology, postoperative complications, morbidity, and mortality were analyzed. RESULTS: A total of 6,317 patients were reviewed and 3,424 (54.20%) of them were malignant; 2,128 patients in group A and 4,189 in group B. Patients in group A had better pathological diagnosis, inferior extent of lymph node metastasis, less surgical complexity, fewer postoperative complications, and longer disease-free survival (DFS). CONCLUSIONS: Thyroid operations were safer and involved fewer postoperative complications when thyroid nodules were <1 cm and patients who were diagnosed with malignant thyroid disease had superior prognoses. Underdeveloped regions of China should diagnose and treat thyroid nodules <1 cm early.