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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] The paper was to identify Alternaría alternata causing leaf spot disease on Huangdi banana in China. [Methods] Fungal isolates were isolated and identified by morphological features, molecular identification and pathogenicity test. [Results] There were light to dark brown, tiny oval spots on leaves. The causal agent isolated from affected leaves was identified as A. alternata based on the morphological properties, coupled with sequence analyses of the internal transcribed spacer (IIS) region, large subunit ribosomal DNA (LSU rD-NA) and the translation elongation factor 1-alpha (TEF-la) gene. Koch's postulates were fuEilled by successful re-isolation of pathogen from the artificial inoculated leaves. [ Conclusions] To our knowledge, this is the first report of leaf spot caused by A. alternata on Huangdi banana in China. The identification of A. alternata as the causal agent of the observed leaf spot disease on Huangdi banana is critical to the prevention and control of this disease in the future. [ABSTRACT FROM AUTHOR]

[Objectives] The paper was to study molecular characterization, morphology and pathogenicity of Curvularia pseudobrachyspora, a new causal agent of leaf spot on banana. [Methods] Banana (Musa acuminate') leaves with streaks or long ellipse-shaped lesions were sampled in an orchard of Danzhou City, Hainan Province, China in 2021. Fungus isolates were isolated from the diseased tissues and further identified as C. pseudobrachyspora based on morphological characteristics of colony, conidiophore and spore, phylogenetic analyses of the ITS region, GAP DP and TET-la genes. [Results] In the pathogenicity test, the fungus re-isolated from inoculated leaves with necrotic lesions was identified morphologically and molecularly, fulfilling Koch's postulates. [Conclusions] C. pseudobrachyspora is a new pathogen causing leaf spot of banana in China and the world. [ABSTRACT FROM AUTHOR]

[Objectives] The study was to confirm the etiological agent of leaf spot on banana in Yunnan Province of China. [Methods] Fungus isolates were isolated from the diseased tissues, and cultured to observe the morphological characteristics of colony and spore. Furthermore, phylogenetic analyses and pathogenicity test were also conducted to confirm the pathogen. [Results] The fungus isolated from the diseased tissues was identified as Neopestalotiopsis clavispora. [Conclusions] N. clavispora is a new pathogen causing leaf spot of banana. This research provides the first description of N. clavispora as a causal agent on banana in China, and adds new insights related to the host range of N. clavispora. [ABSTRACT FROM AUTHOR]

[Objective] The paper was to screen effective fungicides to control Cordana leaf spot caused by Neocordana musae. [Method] The toxicities of six fungicides against mycelial growth of N. musae were measured by the method of mycelium growth inhibition. [Result] The average EC50 values of six fungicides against mycelial growth ranged from 0.102 9 to 504.065 µg/mL. Among them, 22.5% picoxystrobin SC and 12.5% epoxiconazole SC showed strong inhibitors' activity on mycelial growth, with the average EC% values of 0.102 9 and 0.685 1 µg/mL, respectively; followed by 50% thiophanate-methyl SC, with an average EC50 value of 1.993. 80% Azoxystrobin WG showed a relatively low sensitivity against N. musae, with an average EC50 value of 504.046. [Conclusion] The six fungicides tested have great value in preventing and controlling Cordana leaf spot. 22.5% Picoxystrobin SC, 12.5% epoxiconazole SC and 50% thiophanate-methyl SC have better inhibitory activities on mycelial growth of N. musae, and can be further used in field trials. [ABSTRACT FROM AUTHOR]

[Objectives] The paper was to identify the causal agent of leaf spot of banana in Hainnan, China. [Methods] Fungus isolates were isolated from the diseased tissues, and morphological characteristics of colony and spore were observed. Furthermore, phylogenetic analyses and pathogenicity test were conducted to confirm the pathogen. [ Results] The fungus isolates from the diseased tissues was identified as Curvularia geniculata. [Conclusions] C. geniculata is a new pathogen causing leaf spot of banana in Hainan, China. This finding will help to broaden the distribution and host range of C. geniculata, indicating that it poses potential damage to banana in China. [ABSTRACT FROM AUTHOR]

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]

[Objective] This study aimed to develop a PCR assay for detecting Xanthomonas campestris pv. mangiferaeindicae (Xcm) in culture and in planta. [Method] Primers (XcmHF and XcmHR) were designed based on the partial sequence of hrpB gene from xanthomonads to develop a PCR assay for Xcm. Furthermore, specificity and sensitivity of the primer pairs were analyzed in detection of genomic DNA and cell from Xcm. [Result] Amplication was positive only with genomic DNA from positive control ATCC11637 and 12 Xcm strains; no PCR products were amplified with genomic DNA from ten other xanthomonads and seven other bacterial species. The sensitivity of detection was 2.4 pg/μl genomic DNA, and 1.8 × 104 CFU/ml cells. The primers also worked well for pathogen detection in direct PCR assays of Xcm colonies grown on liquid medium and in PCR assays of total DNA from leaf, branch and fruit lesions. [Conclusion] A PCR assay was successfully established for rapid detection of Xcm in culture and in planta. [ABSTRACT FROM AUTHOR]

Light microscopy of the prepenetration process of Phyllosticta musarum, the banana freckle disease causal agent, on banana leaf was conducted. Germination of conidia started within 2?3h after inoculation (AI) in a film of water at 25C. More than 50 and 90% of conidia germinated at 12 and 72h AI at 25C, respectively. The germination of a conidium usually produced one germ tube, and occasionally two germ tubes, which were borne at the side of the conidium. However, only one germ tube developed into a mature appressorium. Appressoria were dark brown in colour and had different shapes. Most of them were round or slightly lobed. Appressorium formation initiated at 6h AI, and the appressorial formation rate reached more than 50 and 80% at 24 and 48h AI, respectively. A reddish-brown necrosis of host cells appeared under the appressoria as they were forming and was seen at 120h AI. Most appressoria were formed in the grooves between adjacent epidermis cells. The pathogen seems to penetrate directly through the epidermal cuticle layer of the host by forming appressoria and infection pegs. [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.