Search

Plant height is an important and valuable agronomic trait associated with yield and resistance to abiotic and biotic stresses. Dwarfism has positive effects on plant development and field management, especially for tall monocotyledon banana (Musa spp.). However, several key genes and their regulation mechanism of controlling plant height during banana development are unclear. In the present study, the popular cultivar ‘Brazilian banana’ (‘BX’) and its dwarf mutant (‘RK’) were selected to identify plant height-related genes by comparing the phenotypic and transcriptomic data. Banana seedlings with 3–4 leaves were planted in the greenhouse and field. We found that the third and fourth weeks are the key period of plant height development of the selected cultivars. A total of 4563 and 10507 differentially expressed genes (DEGs) were identified in the third and fourth weeks, respectively. Twenty modules were produced by the weighted gene co-expression network analysis (WGCNA). Eight modules were positively correlated with the plant height, and twelve other modules were negatively correlated. Combining with the analysis of DEGs and WGCNA, 13 genes in the signaling pathway of gibberellic acid (GA) and 7 genes in the signaling pathway of indole acetic acid (IAA) were identified. Hub genes related to plant height development were obtained in light of the significantly different expression levels (|log2FC| ≥ 1) at the critical stages. Moreover, GA3 treatment significantly induced the transcription expressions of the selected candidate genes, suggesting that GA signaling could play a key role in plant height development of banana. It provides an important gene resource for the regulation mechanism of banana plant development and assisted breeding of ideal plant architecture.

To improve essential oil quality, especially to reserve the thermal instability of compounds, supercritical CO2 extraction (SFE) was applied to recover essential oil from Cymbopogon citronella leaves. A response surface methodology was applied to optimize the extraction process. The highest essential oil yield was predicted at extraction time 120 min, extraction pressure 25 MPa, extraction temperature 35°C, and CO2 flow 18 L/h for the SFE processing. Under these experimental conditions, the mean essential oil yield is 4.40%. In addition, the chemical compositions of SFE were compared with those obtained by hydrodistillation extraction (HD). There were 41 compounds obtained of SFE, while 35 compounds of HD. Alcohols and aldehydes were the main compositions in the essential oils. Furthermore, the antioxidant activities and antimicrobial of essential oils obtained by HD and the evaluated condition of SFE were compared. Results showed that the antioxidant activities of SFE oil are better than those of HD. Minimum inhibitory concentrations (MICs) were determined by the microdilution method. Essential oil obtained from SFE and HD exhibited a significant antimicrobial activity against all tested microorganisms. It is confirmed that the SFE method can be an alternative processing method to extract essential oils from Cymbopogon citronella leaves.

Fusarium oxysporum f. sp. cubense (Foc), the causal agent of Fusarium wilt (Panama disease), is one of the most devastating diseases of banana (Musa spp.). The Foc tropical race 4 (TR4) is currently known as a major concern in global banana production. No effective resistance is known in Musa to Foc, and no effective measures for controlling Foc once banana plants have been infected in place. Early and accurate detection of Foc TR4 is essential to protect banana industry and guide banana planting. A real-time fluorescence loop-mediated isothermal amplification assay (RealAmp) was developed for the rapid and quantitative detection of Foc TR4 in soil. The detection limit of the RealAmp assay was approximately 0.4 pg/µl plasmid DNA when mixed with extracted soil DNA or 10(3) spores/g of artificial infested soil, and no cross-reaction with other relative pathogens were observed. The RealAmp assay for quantifying genomic DNA of TR4 was confirmed by testing both artificially and naturally infested samples. Quantification of the soil-borne pathogen DNA of Foc TR4 in naturally infested samples was no significant difference compared to classic real-time PCR (P>0.05). Additionally, RealAmp assay was visual with an improved closed-tube visual detection system by adding SYBR Green I fluorescent dye to the inside of the lid prior to amplification, which avoided the inhibitory effects of the stain on DNA amplification and makes the assay more convenient in the field and could thus become a simple, rapid and effective technique that has potential as an alternative tool for the detection and monitoring of Foc TR4 in field, which would be a routine DNA-based testing service for the soil-borne pathogen in South China.

Objectives This study aimed at investigating the applicability of a novel index based on waist circumference (WC) and triglyceride (TG) which was named lipid accumulation product (LAP) in the Southern Chinese population, and compared the predictive effects of LAP and other obesity indicators on hypertension risk. Moreover, this study investigated the interactive effects of LAP and family history of hypertension. Methods A total number of 2079 of community-dwelling adults in Southern China were enrolled in this cross-sectional study. The participants underwent questionnaire surveys, anthropometric tests and laboratory examinations. Themultinomial logistic regression model and receiver operating characteristic curves, including LAP, body mass index (BMI), waist-to- hip ratio (WHR), WC and TG, were used to assess the association between hypertension risk and obesity indexes. The interaction effects were evaluated by relative excess risk of interaction (RERI), attributable proportion due to interaction (AP) and synergy index (SI). Results Higher LAP levels have a relatively higher risk of having hypertension in both sexes (males: adjusted OR=2.79 per SD increase, 95% CI 1.43 to 5.44, p<0.001; females: adjusted OR=3.15, 95% CI 1.56 to 6.39, p<0.001). LAP (area under the curve=0.721; 95% CI 0.680 to 0.761) is a better indicator in identifying hypertension risk than BMI, WHR and TG in females, but WC performed better in males. A significant interaction between LAP and family history of hypertension was observed in males (RERI=1.652, 95% CI 0.267 to 3.037; AP=0.516, 95% CI 0.238 to 0.794; SI=3.998, 95% CI 0.897 to 17.820), but there is no statistically significant difference in females. Conclusions LAP significantly associates with hypertension risk in the Southern Chinese population. It has better performance than BMI, WHR and TG on predicting hypertension risk of the Southern Chinese female population. Moreover, LAP and family history of hypertension might synergistically increase the risk of hypertension [ABSTRACT FROM AUTHOR]

Backgroud and Purpose: Hypertension has been regarded as one of the most common chronic diseases reported in different studies, and handgrip strength is a good indicatorof anindividual’s overall health. However, few studies have concentrated on investigating the relationship between hypertension and handgrip strength, especially for the middle-aged and elderly population in the community. Therefore, the purpose of this study was to explore the association of handgrip strength with the risk of hypertension. Methods: A cross-sectional study was conducted using a multi-instrument questionnaire. A total of 1152 participants aged 45 and older were included in this study. Handgrip strength, social-demographiccharacteristics, behavioral lifestyle and health-related variables were collected. Binary logistic regression was employed to analyse the relationship. Results: Handgrip strength was positively related to the risk of hypertension. Binary logistic regression models revealed that the increase of handgrip strength was significantly associated with the reduction of hypertension risk in female after adjusting forsocial-demographic characteristics, behavioral lifestyle and health-related variables (OR [95%CI] =0.265 [0.089-0.787]). In addition, after stratifying by age groups, the significant association was still existing in 60-74 years and ≥75 years of female groups, respectively(OR [95%CI] =0.158 [0.032-0.779]; (OR [95%CI] =0.009 [0.000-0.409]). No significant associations were observed in male after adjusting variables. Conclusion: stronger handgrip strength was association with the lower risk ofhypertension for the elderly female population. Abbreviations: BMI: body mass index; DBP: diastolic blood pressure; HC: hip circumference; SBP, systolic blood pressure; WC: waist circumference; WHC: hip–waist relation.