Effective Disease Management Strategies Research Articles

In silico analysis of secreted effectorome of the rubber tree pathogen Rigidoporus microporus highlights its potential virulence proteins

Rigidoporus microporus, the causative agent of the white root rot disease of rubber trees, poses a significant threat to natural rubber production worldwide. Understanding the molecular mechanisms facilitating its pathogenicity would be crucial for developing effective disease management strategies. The pathogen secretes effector proteins, which play pivotal roles in modulating host immune responses and infection. In this study, in silico analyses identified 357 putative secreted effector proteins from the R. microporus genome. These were then integrated into previous RNA-seq data obtained in response to rubber tree latex exposure. Annotation of putative effectors suggested the abundance of proteins in several families associated with the virulence of R. microporus, especially hydrophobin proteins and glycoside hydrolase (GH) proteins. The contribution of secreted effectors to fungal pathogenicity was discussed, particularly in response to rubber tree latex exposure. Some unknown highly expressed effectors were predicted for the protein structures, revealing their similarity to aminopeptidase, ubiquitin ligase, spherulin, and thaumatin protein. This integrative study further elucidates the molecular mechanism of R. microporus pathogenesis and offers alternative targets for developing control strategies for managing white root rot disease in rubber plantations.

The Effect of Treatment Adherence on Health Status of Outpatients with Chronic Obstructive Pulmonary Disease

Adherence to COPD treatment plays a crucial role in patient health outcomes. Understanding the correlation between treatment adherence and health status is vital for clinicians to develop effective disease management strategies. This study aimed to examine treatment adherence and its impact on the health status of COPD patients, specifically focusing on the effects of adhering to inhaled medications and breathing exercises. A cross-sectional study involving 420 outpatients diagnosed with COPD was conducted. The study encompassed administering questionnaires, observing patient breathing exercises, and measuring ventilatory function. Results showed that only 36.9% of participants adhered to treatment, with 44.7% following inhaler protocols and 36.9% regularly engaging in breathing exercises. The patients who were non-adherent exhibited a 0.3-fold increase in disease severity compared to the adherent group (p = .002). These findings suggest that consistent adherence to treatment, including inhaled medications and breathing exercises, may positively affect health status by reducing disease severity and airway obstruction in COPD patients. To address this, we recommend that home care clinicians implement a post-discharge assessment and intervention program. This program should focus on educating patients about the importance of treatment adherence and promoting behaviors that reinforce adherence to prescribed therapies.

Penicillium species associated with postharvest blue mold rots of garlic in Serbia.

Garlic (Allium sativum L.) is an important plant because of its medicinal and gastronomical benefits. The host can be affected by different plant pathogens, among which Penicillium species are one of the most important rot agents, of stored garlic and other stored food products. This research resolves the etiology of blue mold rots associated with garlic in Serbia. Penicillium-like isolates were collected (2016-2022) from diseased stored garlic bulbs in Serbia and identified using a polyphasic approach. Detailed characterization of the obtained cultures was performed using three solid media, three incubation temperatures, molecular and phylogenetic analyses of four molecular loci [internal transcribed spacer (ITS), beta-tubulin (BenA), calmodulin (CaM) and DNA-dependent RNA polymerase II second largest subunit (RPB2)] and the pathogenicity assay. Five Penicillium species, i.e. P. allii, P. glabrum, P. italicum, P. polonicum, and P. psychrotrophicum were identified and confirmed as postharvest pathogens of garlic. Herein, we report for the first time the pathogenicity of P. psychrotrophicum and P. italicum on garlic. Findings from this study provide insights into the previously unknown diversity of Penicillium fungi responsible for garlic bulb decay in Serbia, and will help in the assessment of the phytosanitary status of this crop, as well as the creation and application of effective disease management strategies.

First Report of Phytophthora cinnamomi causing root rot of avocado trees in Greece.

In September 2023, thirty declining 30-year-old avocado (Persea americana) trees ('Hass' grafted on 'Zutano' seedlings) were detected in a 1.5-ha orchard in the island of Crete (Chania region). Crown symptoms encompassed wilting and leaf chlorosis, advancing to defoliation and extensive dieback. Tap and feeder roots decayed and brown discoloration of root tissues was evident on heavily infected trees. The disease was severe and widespread, resulting in a 5% mortality rate among 300 trees. The pathogen was isolated with a modified soil baiting technique (Ferguson and Jeffers, 1999). Surface disinfected avocado fruits were immersed in water containing soil samples. Following a period of 2 to 8 days, tissue fragments from the resulting necrotic lesions on the fruit surface were transferred on ΡΑRP medium and subsequently incubated at 20°C (Ferguson and Jeffers, 1999). Three isolates (AV2, AV12 and AV11a) were obtained by transferring single hyphal tips to new Petri dishes containing V8 juice agar. They were grown at 20˚C and used for identification after 10 days. Isolates formed coralloid colonies with abundant clustered spherical hyphal swellings and terminal or intercalary (ratio 1:5) thick-walled chlamydospores measuring 20 to 36 μm (avg 29±0.8 μm) with characteristic thick walls (avg 1.2±0.2 μm). Sporangia, produced in non-sterile soil-extract water, were ovoid to obpyriform, persistent, non-papillate, 32 to 81 μm (avg 56±4.8 μm) long and 20 to 42 μm (avg 31±3.2 μm) wide (n=100). Isolates were heterothallic as they did not produce oospores in single cultures. Based on the morphological traits the isolates were identified as Phytophthora cinnamomi (Erwin and Ribeiro 1996). The internal transcribe spacer region (ITS) including ITS1, 5.8S rDNA region, and ITS2 as well as the cytochrome c oxidase subunit I (coxI) gene of the three representative isolates wereamplified with ITS1/ITS4 and FM83/FM84 primers, respectively (White et al. 1990; Martin and Tooley 2003), and sequenced (GenBank acc. PP506613 to PP506615 and PQ063867 to PQ063869, respectively). BLAST search revealed almost 100% identity with the sequences of P. cinnamomi ex-isotype isolate (KC478663 and KU899315 respectively). Pathogenicity tests using isolate AV2 were conducted following the soil infestation method (Jung et al. 1996) using six-year-old avocado 'Zutano' seedlings. Six non-inoculated plants treated with vermiculite-multivitamin juice mixture were used as controls. Plants (1 m tall) were grown in pots under greenhouse conditions and watered regularly. Six weeks post inoculation, all inoculated trees showed chlorosis, wilting and root rot, while control plants remained symptomless. Symptoms were similar to those observed in the field and the pathogen was re-isolated and molecularly identified as previously described. This study presents the first documented occurrence of P. cinnamomi, widely regarded as the most destructive avocado pathogen globally, on avocado crops in Greece (Rodger et al. 2019). Additionally, this marks the first recorded presence of this pathogen on the island of Crete, regardless of the host species. The accurate identification of Phytophthora species associated with avocado root rot is essential for implementing an effective disease management strategy, particularly in the selection of appropriate disease-resistant rootstocks.

Morphological and Molecular Identification and Mating Type Detection of Chalkbrood Fungal Pathogen <i>Ascosphaera apis</i> in <i>Apis mellifera</i> L. in Southern India

Chalkbrood Ascosphaera apis is a fungal brood pathogen that exerts considerable biotic stress on honey bees worldwide. Chalkbrood was noticed at Coimbatore in Apis mellifera colonies for the first time. Precise identification of the fungal pathogen and their mating types is crucial to develop effective disease management strategies. Hence, the present study aimed to isolate and identify fungal pathogen morphologically and genomically. Scanning Electron Microscopic (SEM) analysis was done and confirmed the essential morphological characteristics of the isolated fungus such as spore cysts (51-86 µm in diameter), spore balls (8-15 µm in diameter), and ascospores (1.7-2.6 µm in length). Molecular characterization using internal transcribed sequence (ITS)-PCR of the fungal isolate indicated 99-100% sequence similarity to A. apis. In addition, the multiplex PCR assay was performed and the mating types MAT1-1 and MAT1-2 were successfully detected and named TNAU CBD MAT1 and TNAU CBD MAT2, respectively.

Discover the Most Effective Disease Management Strategies for Fusarium Dry Rot of Potato through Comprehensive Bio-assay of Three Techniques (Chemical, Plant extracts, and Bio-control)

Potato (Solanum tuberosum) is a multicultural staple food and cash crop. Unfortunately, production of potatoes is predominantly constrained by diseases including dry rots. To evaluate management of dry rots, three in vitro sub-trials were set up using the completely randomized design with each treatment replicated thrice for each trial. Firstly, synthetic fungicides were assayed against Fusarium oxysporum f.sp. tuberosi. Secondly, plant extracts were assessed against F. oxysporum. Finally, the efficacy of Trichoderma harzianum applied against F. oxysporum was evaluated. The colony radii were measured. The inhibition of F. oxysporum by Ketoconazole (at 100% concentration) was significantly (p≤0.05) highest, followed by Ketoconazole (50% concentration), Itraconazole (100% concentration), Itraconazole (50% concentration), Sulphur (100% concentration), Ridomil (100% concentration), Sulphur (50% concentration), and finally Ridomil (50% concentration). Percentage inhibition of the growth of the Fusarium species by fungicides ranged from 39.5-95.7%. Blue gum (Eucalyptus globulus) (at 100% concentration) gave the highest inhibition, followed by blue gum (50% concentration), Sweet alligator-pepper (Aframomum melegueta) at 100% concentration, locust bean (Parkia biglobosa) at 100% concentration, Sweet alligator-pepper (50% concentration), candle bush (Senna alata) (100% concentration), locust bean (50% concentration), and Senna alata (50% concentration) in descending order of percentage inhibition. Plant extracts caused a percentage inhibition of the fungus between 20.6-100% inhibition with time. Inhibition of Fusarium by T. Harzianum isolate BGMZ4 was significantly (p≤0.05) highest, followed by T. Harzianum isolate NSBM then T. Harzianum isolate BGMZ3. Control of F. Oxysporum by T. Harzianum ranged from 23.5-94.1% inhibition. All the methods evaluated successfully inhibited the pathogen compared to the control.

Machine learning investigation of tuberculosis with medicine immunity impact

Tuberculosis (T.B.) remains a prominent global cause of health challenges and death, exacerbated by drug-resistant strains such as multidrug-resistant tuberculosis MDR-TB and extensively drug-resistant tuberculosis XDR-TB. For an effective disease management strategy, it is crucial to understand the dynamics of T.B. infection and the impacts of treatment. In the present article, we employ AI-based machine learning techniques to investigate the immunity impact of medications. SEIPR epidemiological model is incorporated with MDR-TB for compartments susceptible to disease, exposed to risk, infected ones, preventive or resistant to initial treatment, and recovered or healed population. These masses' natural trends, effects, and interactions are formulated and described in the present study. Computations and stability analysis are conducted upon endemic and disease-free equilibria in the present model for their global scenario. Both numerical and AI-based nonlinear autoregressive exogenous NARX analyses are presented with incorporating immediate treatment and delay in treatment. This study shows that the active patients and MDR-TB, both strains, exist because of the absence of permanent immunity to T.B. Furthermore, patients who have recovered from tuberculosis may become susceptible again by losing their immunity and contributing to transmission again. This article aims to identify patterns and predictors of treatment success. The findings from this research can contribute to developing more effective tuberculosis interventions.

Resistance of Ascochyta rabiei isolates from chickpeas (Cicer arietinum L.) to fungicides

Ascochyta blight is a disease that causes significant yield losses in chickpea crops in Turkey under favorable environmental conditions. The fungal pathogen Ascochyta rabiei is the causative agent of this disease. The antifungal activity of previous fungicides against A. rabiei was not effective due to the heterothallic nature of the fungus. The aim of this study was to determine the sensitivity of A. rabiei to fungicides (25.2 g kgˉ1 boscalid + 12.8 g kgˉ1 pyraclostrobin; 50% tebuconazole + 25% trifloxystrobin; 62.5 g Lˉ1 propiconazole + 37.5 g Lˉ1 azoxystrobin; 80% thiram; 80% kükürt (sulphur); 80% mancozeb; 80% maneb) under in vitro and field conditions. Pure cultures of A. rabiei were isolated from infected chickpea plants collected in Boğazlayan, Sarıkaya, Sorgun, Merkez and Yerköy. A total of 14 A. rabiei isolates and 4 references were evaluated. The field test was conducted at Yozgat Bozok University, Yerköy Agricultural Application and Research Center Station. The trials began on March 14, 2021. The experimental area was divided into plots and the susceptible chickpea variety Sarı98 was used for the study. Two artificial inoculations were carried out approximately on the 40th and 80th days after sowing. Twenty-four hours after inoculation, the chickpea plants were sprayed with the fungicides Nativo® WG 75, Bellis®, Dikotan® M45 and Thiovit Jet® using a handheld sprayer. In vitro testing revealed that A. rabiei was resistant to kükürt (sulphur), thiram, maneb, and mancozeb. A field study showed that the percentage of A. rabiei isolates treated with the mancozeb fungicide was between 14 and 21% of the control. Therefore, effective disease management strategies should include not only the use of fungicides, but also alternative approaches such as the use of resistant varieties. Moreover, the study focused on phenotypic resistance and suggests that future research should investigate the genetic and molecular mechanisms underlying A. rabiei resistance to enable better resistance management.

Unravelling the complex interplay of age, comorbidities, and multimorbidities in COVID-19 disease progression: Clinical implications and future perspectives

IntroductionThe COVID-19 infection as an inflammatory disease has posed significant challenges to global public health due to multi-factor risks associated with it leading to disease severity and mortality. Understanding the effect of age and comorbidities on overall disease progression is crucial to identify highly susceptible individuals and to develop effective disease management strategies in a resource limited country like Pakistan. MethodologyA retrospective study was conducted on hospitalized COVID-19 patients to assess the prevalence of various comorbidities among different age groups and their effect on disease severity and mortality rate. ResultsIn this retrospective study, a cohort of 618 hospitalized COVID-19 patients was analyzed, consisting of 387 males (62.6 %) and 231 females (37.4 %). Notably, the young age group (15–24 years), had the lowest frequency of hospitalized COVID-19 patients, while no case was observed in children (≤14 years) showing a significant association (p < 0.001) of age and disease prevalence. Comorbidities were observed in 63.9 % of COVID-19 patients including hypertension (HTN), diabetes mellitus (DM), ischemic heart diseases (IHD), asthma, chronic kidney disease (CKD) and tuberculosis (TB). The most common comorbidities were HTN (42.1 %) followed by DM (33.8 %), IHD (16.5 %), asthma (11.2 %), CKD (7.9 %) and TB (1.9 %).Furthermore, the study revealed a significant association between comorbidities, age groups, and the need for non-invasive ventilation (NIV) (p < 0.001), mechanical ventilation (MV) (p < 0.001), and intensive care unit (ICU) admission (p < 0.001). Patients with specific comorbidities and those in the older age group (≥65 years) demonstrated a higher need for these interventions. However, patients without any comorbidity consistently exhibited the highest cumulative proportion of survival at each time point, indicating better overall survival outcomes. In contrast, patients with multimorbidities of DM/HTN/IHD, HTN/IHD, and DM/HTN/CKD had comparatively lower survival rates and higher mortality rates (p < 0.001). ConclusionThis research highlights the significant impact of age, comorbidities and multimorbidities on the severity and mortality of COVID-19 patients. It highlights the importance of considering these factors in tailoring effective management strategies for patients with COVID-19 or other infectious respiratory diseases.

Molecular detection of avian pathogens in poultry red mite (Dermanyssus gallinae) in Algerian layer farms as a potential predictive tool

The poultry red mite Dermanyssus gallinae is a hematophagous ectoparasite of layer hens. Infestations with poultry red mites pose an increasing threat to the egg production industry, causing serious problems to animal health and welfare, directly or indirectly as a vector of several infectious agents. In this study, we aimed to investigate common avian pathogens in mites. The mite samples were collected from 58 poultry farms in 7 regions accounting for more than 70 % of the national egg production in Algeria. The presence of 13 avian pathogens was detected using DNA and RNA samples from mites collected. Results revealed significant associations between PRM and potential pathogens such as Escherichia coli, Salmonella enterica, fowlpox virus, and gallid herpesvirus 1. Pathogen detection in Dermanyssus gallinae could serve as an early diagnostic or a risk analysis tool for infectious diseases in poultry farms, facilitating effective disease management strategies. Despite further research being necessary to address uncertainties, such a strategy could be used to enhance the integrated management of poultry health.

First Report of Colletotrichum gigasporum causing Anthracnose of chili pepper in South Korea.

Anthracnose, a destructive fungal disease, poses a significant threat to chili pepper (Capsicum annuum L.) production worldwide (de Silva et al. 2019). In South Korea, anthracnose outbreaks have traditionally been attributed to several Colletotrichum species such as C. gloeosporioides and C. acutatum. About 10% of the yield (chili production) is lost annually in South Korea due to chili anthracnose (Oo et al. 2020). During field surveys conducted in August 2017, symptomatic lesions resembling anthracnose were observed on chili pepper in two farmer's fields (Gochang and Cheongyang) in South Korea. Affected fruits exhibited characteristic symptoms, including circular sunken lesions with dark margins and abundant orange spore masses on the surface. About 20% of chili pepper fruit were affected in each field with an area of about 0.2 ha. Five putative Colletotrichum spp. isolates were obtained from six affected fruits (three from each field) following the procedure described by Cai et el. (2009). Three isolates (C01049, C01111, and C01115), representing each location, were selected to identify at the species level. Colonies on potato dextrose agar (incubated at 25°C in the dark for 7 days) were cottony with entire margins, white aerial mycelium and dark gray in the center. Conidia were hyaline, aseptate, cylindrical with bothnds round, and 17.8 - 30.5 × 6.0 -10.0 µm (mean 23.8 ×7.9 μm, n = 30). Appressoria were dark brown, irregular but mostly ovoid with smooth walls. These morphological features align with those of Colletotrichum spp. within the Colletotrichum gigasporum species (Liu et al. 2014). The identity of the pathogen was further confirmed through multi-locus phylogenetic analysis. The target genes including ITS, ACT, CHS-1, GAPDH, TUB2, and GS were amplified and sequenced using the primer sets ITS1/ITS4, ACT 512F/ ACT-783R, CHS-79F/ CHS-345R, GDF/GDR, T1/Bt2b, and GSF1/GSR1, respectively (Weir et al. 2012; Liu et al. 2014). The resulting sequences were deposited in GenBank (accession no: ITS: MT605261, MT605262, LC823714; ACT: MT612991, MT612992, LC823718; CHS-1: MT612993, MT612994, LC823717; GAPDH: LC811375, LC811376, LC823716; TUB2: MT612997, MT612998, LC823715; GS: LC811377, LC811378, LC823719). The constructed Bayesian and maximum likelihood tree based on combined sequences of ITS, ACT, CHS-1, GAPDH, TUB2, and GS confirmed the identification of the isolates (C01049, C01111, C01115) as C. gigasporum. Pathogenicity tests were conducted by inoculating healthy chili fruit with 70 µL of a conidial suspension (1×106 conidia /mL) of pure cultures of the isolates. The conidial suspension was applied on 10 wounded or 10 non-wounded fruit. The same number of fruit were treated with sterile distilled water as controls. Within 5 days of inoculation, symptoms consistent with anthracnose developed on the inoculated wounded fruit, whereas non-wounded and control fruit remained asymptomatic. This experiment was repeated twice. Colletotrichum gigasporum was re-isolated from diseased tissue of inoculated fruit. Colletotrichum gigasporum has been identified as the cause of anthracnose on Dalbergia odorifera, Carica papaya in China, and Brassica oleracea in India (Wan et al., 2018; Saini et al. 2022; He et al. 2023). To the best of our knowledge, this report marks the first documented instance of C. gigasporum causing anthracnose of chili pepper in South Korea. These results indicate that various species of Colletotrichum can be the fungi causing chili pepper anthracnose. The findings of this study emphasize the need for effective disease management strategies to mitigate impact of C. gigasporum on chili pepper cultivation in the region.

The trade potential of grain crops in the countries along the Belt and Road: evidence from a stochastic frontier model

This study employs the stochastic frontier model (SFM) to analyze trade potential and efficiency in wheat and maize among Belt and Road Initiative (BRI) countries from 2002 to 2021, encompassing 45 countries for wheat trade and 55 for maize trade. The empirical findings reveal that economic development level, population growth, government efficiency, political stability, and regulatory quality are critical determinants of trade efficiency. Notably, World Trade Organization (WTO) membership exhibits a negative correlation with trade efficiency, potentially reflecting challenges in rule implementation and opportunity utilization among member states. In the context of maize trade, increased arable land area is inversely associated with efficiency, suggesting potential issues in managing large-scale agricultural regions or optimizing land use. The BRI’s impact on trade efficiency varies across countries, with Turkey and Hungary showing improved wheat trade efficiency, while Ethiopia and Georgia experienced declines. During the COVID-19 pandemic, effective disease management strategies and diversified trade mechanisms significantly influenced trade efficiency. Furthermore, the study reveals that larger economies do not necessarily outperform small and medium-sized economies in terms of trade potential. These findings contribute significantly to the literature on agricultural trade and offer valuable insights for policymakers, emphasizing the importance of enhancing government efficiency, political stability, and regulatory quality in the context of regional economic development initiatives such as the BRI. This research underscores the need for tailored approaches to trade policy and agricultural management, considering the unique characteristics and challenges faced by different economies along BRI.

Mapping serogroup distribution and seroprevalence of leptospirosis in livestock of Assam, Northeastern State of India: Unveiling uncommon Leptospira serogroups

Leptospirosis is a significant zoonotic disease affecting livestock, leading to reproductive issues and economic losses. Despite its endemic status in India, research has predominantly focused on coastal regions, leaving the North Eastern Region (NER) underexplored. This study aims to investigate the seroprevalence and serogroup distribution of leptospirosis in livestock across Assam, a major state in the North Eastern Region (NER) of India. Serum samples (n=811) from cattle, buffalo, sheep, goats, and pigs were collected between 2016 and 2019 and screened using the Microscopic Agglutination Test (MAT) for 24 serogroups. The overall seroprevalence was 22.9 % (186/811), with highest prevalence in cattle (26.2 %) and buffalo (25 %), followed by small ruminants (19.8 %) and pigs (18.6 %) . Notably, uncommon serovars such as Mini (28.8 %), Manhao (12.4 %), and Cynopteri (7.5 %) were identified, indicating a unique epidemiological pattern in Assam. High seroprevalence was observed in districts like Bongaigaon (66.7 %), Kamrup Metropolitan (50.0 %), and Nalbari (40.0 %), emphasizing the need for targeted intervention strategies. The presence of these uncommon serogroups, typically found in neighbouring countries and other regions, suggests potential transboundary transmission from these countries. This study provides valuable insights into the seroprevalence and serogroup distribution of leptospirosis in Assam's livestock, highlighting the need for region-specific surveillance and control measures. These findings underscore the importance of understanding the local epidemiological landscape to develop effective disease management and prevention strategies, ultimately reducing the impact of leptospirosis in the NER of India.

Smart agriculture: An intelligent approach for apple leaf disease identification based on convolutional neural network

AbstractPlant diseases pose a significant threat to global agricultural productivity and food safety. Early detection and accurate identification of these diseases are essential for effective disease management strategies. Traditional plant disease identification mainly relies on manual observation and experienced expert judgement, which has the disadvantages of being time‐consuming, labour‐intensive and low efficiency. Given the above problems, this study proposes a method for identifying apple leaf diseases based on a convolutional neural network combining hybrid attention and bidirectional long short‐term memory (BiLSTM). Appropriate apple leaf disease samples were selected from multiple public data sets to form an experimental data set. Then, the data set is imported into the improved convolutional neural network for training. Based on the original ResNet18 model, a new convolutional neural network, AppleNet, is constructed by adding a hybrid attention module and modifying the classifier structure. The experimental results show that the average recognition accuracy of AppleNet is 94.66%, which is 2.47% higher than that of the ResNet18 network. In addition, the training time of the model is only slightly increased. The ablation experiment further verified the effectiveness of the model modification. Compared with other advanced models in recognition accuracy and model training time, the superiority of AppleNet is confirmed. This study verifies that deep learning has great potential and application prospects in plant disease identification and provides a new technical solution for intelligent and convenient plant disease identification.

Characterization of Erwinia amylovora isolates from the northern region of Saudi Arabia, including CRISPR genotyping

AbstractFire blight, caused by the bacterium Erwinia amylovora, poses a global threat to the pome fruit industry, leading to reduced yields and significant economic losses. A comprehensive countrywide survey was carried out to determine the possible E. amylovora distribution in pome fruit‐growing regions. During the period 2020–2023, 85 isolates characteristic of E. amylovora were obtained from pear across 23 locations in three main pear‐producing regions (Al‐Jouf, Hail and Tabuk) in northern Saudi Arabia (SA). Isolates were identified using biochemical, molecular and pathogenicity assays. Molecular characterization of Saudi strains was achieved using partial 16S rRNA and rpoB gene sequencing, rep‐PCR (specifically, BOX‐PCR) and CRISPR array analysis. The CRISPR genotyping in particular, using an existing scheme of three CRISPR arrays, CR1, CR2 and CR3, provided consistent patterns of the Saudi isolates with high similarity to those of E. amylovora strains from the UK and France, hinting at a possible origin of the fire blight infections from these countries. Some variation was observed in patterns between local strains, highlighting the importance of continued surveillance and genetic studies for effective disease management strategies. Identification of fire blight in three regions over several years should serve as a warning to the Ministry of Environment, Water and Agriculture in Saudi Arabia, prompting the initiation of a more comprehensive survey and an active disease management programme. This programme should include early detection and advice to growers on prevention and control measures. This is the first scientific study on the occurrence and genetic variability of E. amylovora in Saudi Arabia.

Identification and pathogenicity of Ceratocystis manginecans causing wilt disease on Acacia mangium in Sabah, Malaysia

Abstract. Yunus NM, Maid M, Yong WTL, Anthony FE, Sudin M, Taylor PWJ. 2024. Identification and pathogenicity of Ceratocystis manginecans causing wilt disease on Acacia mangium in Sabah, Malaysia. Biodiversitas 25: 2170-2182. An alarming incidence of wilt disease has been reported in an Acacia mangium plantation in Ulu Kukut, Kota Belud District, Sabah, Malaysia. Infected trees exhibited symptoms such as severe wilting, sapwood discoloration or black lesion, and a fruity-sweet odor emanating from the fermentation exudate at the wound lesion. This is the first investigation of the causal wilt pathogen in a commercial A. mangium plantation in Ulu Kukut, located in the western region of Sabah. This study aimed to identify the causal fungal pathogen from infected A. mangium trees using morphological characterization and DNA sequence comparisons for the regions of Internal Transcribed Spacer (ITS), beta-tubulin 1 (bt1), transcription elongation factor-1 alpha (tef1), guanine nucleotide-binding protein subunit beta-like protein (ms204), and second largest subunits of RNA polymerase II (rpb2). The fungal isolates shared morphological characteristics with the wilt pathogen Ceratocystis sp., including a globose base with a long neck-ended tip with ostiolar hyphae. Sequence-based phylogenetic analysis confirmed the identity of Ceratocystis manginecans, distinguishing them from all other Ceratocystis species. Bioassays inoculating phyllodes and twigs of 1-year-old A. mangium trees confirmed that C. manginecans was the cause of wilt disease. Confirming the identity of the causal agent of the increasingly destructive and severe wilt disease aids in developing effective disease management strategies for Acacia-based plantations.

Insights into the virulence profiles and molecular diversity of Xanthomonas oryzae pv. oryzae isolates associated with bacterial blight of rice in major districts of Karnataka, India

Bacterial leaf blight (BLB), caused by Xanthomonas oryzae pv. oryzae (Xoo), is a devastating disease affecting rice worldwide. In this study, to characterize Xoo isolates and evaluate the effectiveness of various BLB-resistant genes in rice, a set of 29 rice differentials each carrying, single or combinations of BLB resistant genes were used for characterizing Xoo isolates under glasshouse condition. None of the tested isolates were able to show complete virulence across all Near Isogenic Lines (NILs). All isolates varied with degrees of resistance and susceptibility. Notably, isolate KXo-3 exhibited high virulence. Among single BLB resistant genes, IRBB-8 (xa8) and IRBB-13 (xa13) were found highly promising while among two gene combinations, IRBB-51 (Xa4+xa13), IRBB-52 (Xa4+Xa21) and IRBB-53 (xa5+xa13). Among three and four gene combination of BB resistant genes, IRBB-56 (Xa4+xa5+xa13), IRBB-57 (Xa4+xa5+Xa21), IRBB-58 (Xa4+xa13+Xa21), IRBB-59 (Xa5+xa13+Xa21), IRBB-60 (Xa4+xa5+xa13+Xa21), IRBB-63 (xa5+Xa7+xa13) and IRBB-65 (Xa4+Xa7+xa13+Xa21) were resistant against almost all the Xoo isolates. Based on disease reactions, Xoo isolates were grouped into 6 pathotypes, as IXoPt # 1, 2, 4, 5, 17 and 22. IXoPt-22 was highly virulent and IXoPt-1 was least virulent. IXoPt-2 was widely distributed with the maximum distribution frequency of 23.8. Molecular diversity using IS1112 repetitive elements showed that the Xoo isolates were genetically very diverse with three major clusters, I, II and III. The haplotype diversity resulted in 27 haplotypes generation. The isolates of Belagavi, Haveri and Davanagere were very diverse with distinct haplotypes. These findings enhance our understanding of BLB resistance mechanisms and Xoo population diversity, aiding in the development of effective disease management strategies in rice cultivation.

Ethnic differences in physical activity participation when managing gestational diabetes mellitus: a mixed-methods study comparing ethnic Chinese migrants and Australian women

ABSTRACT Background Physical activity is a key component in gestational diabetes mellitus management to optimise glycaemic control and reduce adverse pregnancy outcomes. However, inadequate physical activity during pregnancy is common. Underpinned by a woman-centred pregnancy care model, appropriate strategies targeting patients’ cultural needs may facilitate physical activity participation. Ethnic Chinese migrants have a four-fold higher risk of gestational diabetes mellitus than the Australian Caucasian host population. To identify potentially effective disease management strategies to improve physical activity participation, understanding and comparing ethnic Chinese migrants’ and Caucasian women’s views will provide insights into developing an end-user-informed intervention. Aims This study aimed to compare perceptions and practices around physical activity participation during pregnancy between 44 ethnic Chinese migrants and 39 Australian-born Caucasian women with gestational diabetes mellitus. Methods This mixed-methods study used in-depth, semi-structured audio-recorded interviews, validated pregnancy physical activity questionnaires and pedometers. Qualitative data were thematically analysed and compared between ethnicities. SPSS (SPSS Inc) was used in quantitative data analysis. Data triangulation was made to identify patterns in participant characteristics, physical activity beliefs and participation. Results Despite both ethnic groups doing less physical activity than recommended, Chinese participants were less physically active than Caucasian participants. Chinese participants expressed greater safety concerns about physical activity and opted for a more sedentary lifestyle. Data triangulation indicated that non-Australian-born Chinese participants whose husbands were Asian were overcautious about miscarriage risk related to physical activity, which promoted a sedentary lifestyle. Chinese participants suggested individualised, specific physical activity advice on safe physical activity during pregnancy would mitigate their concerns. Caucasian participants reported that digital step measurement technologies motivated their participation in physical activity. Conclusion Different strategies are suggested by Chinese and Caucasian participants to improve physical activity participation to manage gestational diabetes mellitus among ethnic Chinese and Caucasian populations, which will be evaluated in future interventions.

First Report of Calosphaeria pulchella causing Canker and Twig Dieback of Peach (Prunus persica) in California, U.S.A.

California leads the United States in peach (Prunus persica L.) production, with approximately 505,000 tons produced in 2021 and valued at $378.3 million (California Agriculture Statistics Review, 2021-2022). During the spring and summer of 2023, twig and branch dieback were observed in three peach orchards (cvs. Late Ross and Starn) in San Joaquin County, California. Wood cankers and discoloration also occurred in branches, generally initiating at pruning wounds. Approximately 8 symptomatic twigs or branches per orchard were collected to proceed with the isolation of necrotic tissues on acidified potato dextrose agar (APDA). Isolations consistently yielded colonies of the fungal pathogen Calosphaeria pulchella (Pers. : Fr.) J. Schröt. (Réblová et al. 2004; Trouillas et al. 2012). Pure cultures were obtained by transferring single hyphal tips onto new APDA Petri plates. Colonies on APDA grew dark pink to red or purple in their center, with a white margin. Conidiogenesis was phialidic, producing round conidial masses at the tip of phialides. Conidia were produced abundantly on APDA, and were hyaline, allantoid to oblong-ellipsoidal, 4 to 5.5 (7) × 1.2 to 2.3 μm (n = 60). Two representative isolates (SJC-62 and SJC-64) were selected for genomic DNA extraction and sequencing of the internal transcribed spacer region (ITS) using ITS5/ITS4 universal primers and the beta-tubulin (TUB2) gene region using primers Bt2a and Bt2b. Consensus sequences of the two genes for the two isolates (ITS: PP063990, PP063991; TUB2: PP068303, PP068304) were compared to reference sequences (Réblová et al. 2015; Trouillas et al. 2012) using BLAST analysis. The ITS sequences of SJC-62 and SJC-64 were 99.8 and 99.5% identical to that of C. pulchella ex-type strain CBS 115999 (NR145357) and reference strain SS07 (HM237297); the TUB2 sequences were at least 98.5% identical to that of C. pulchella CBS 115999 (KT716476). Pathogenicity tests were conducted in 2- to 3-year-old healthy branches on 7-year-old peach trees, cvs. Loadel, Late Ross and Starn using the two fungal isolates and a control treatment (1 branch per treatment and 3 branches per tree) on each of 8-tree replicates. Branches were inoculated in June 2023 following wounding with a 5 mm cork borer to remove the bark and placing an agar plug from the margin of 10-day-old colonies on APDA directly into the fresh wound. Sterile agar plugs were used as controls. Inoculation sites were covered with petroleum jelly and wrapped with Parafilm to retain moisture. The experiment was completed twice. After four months, cankers and vascular discolorations developed around the inoculation sites. Length of vascular discoloration in inoculated branches averaged 72, 75, and 79 mm, for the Loadel, Starn, and Late Ross cvs., respectively. Calosphaeria pulchella was re-isolated from inoculated branches at 80 to 100% recovery rate, thus fulfilling Koch's postulates. The average length of vascular discoloration in the control was 13.5 mm and no fungi were recovered from control branches. Calosphaeria canker caused by C. pulchella is a global disease of sweet cherry. Recently, it was reported to cause cankers in peach trees in Chile (Grinbergs et al. 2023). To our knowledge, this is the first report of C. pulchella causing cankers and twig dieback of peach trees in the United States. These findings improve our knowledge of the etiology of canker diseases affecting peach trees and is critical for the development of effective disease management strategies.

Identification of Barley yellow mosaic virus Isolates Breaking rym3 Resistance in Japan.

In early spring 2018, significant mosaic disease symptoms were observed for the first time on barley leaves (Hordeum vulgare L., cv. New Sachiho Golden) in Takanezawa, Tochigi Prefecture, Japan. This cultivar carries the resistance gene rym3 (rym; resistance to yellow mosaic). Through RNA-seq analysis, Barley yellow mosaic virus (BaYMV-Takanezawa) was identified in the roots of all five plants (T01-T05) in the field. Phylogenetic analysis of RNA1, encompassing known BaYMV pathotypes I through V, revealed that it shares the same origin as isolate pathotype IV (BaYMV-Ohtawara pathotype). However, RNA2 analysis of isolates revealed the simultaneous presence of two distinct BaYMV isolates, BaYMV-Takanezawa-T01 (DRR552862, closely related to pathotype IV) and BaYMV-Takanezawa-T02 (DRR552863, closely related to pathotype III). The amino acid sequences of the BaYMV-Takanezawa isolates displayed variations, particularly in the VPg and N-terminal region of CP, containing mutations not found in other domains of the virus genome. Changes in the CI (RNA1 amino acid residue 459) and CP (RNA1 amino acid residue 2138) proteins correlated with pathogenicity. These findings underscore the importance of monitoring and understanding the genetic diversity of BaYMV for effective disease management strategies in crop breeding.