A Bioassay That Yields Quantifiable Symptoms of Cucurbit Yellow Vine Disease Caused by .

Cucurbit yellow vine disease (CYVD), which is caused by the gram-negative bacterium and transmitted by squash bugs ( DeGeer), is a devastating disease of cucurbit crops that is emerging rapidly in the eastern half of the United States. The lack of a robust pathogenicity assay for CYVD in the laboratory has hampered functional tests using genomic sequences to investigate the biology of this phytopathogen. In this study we developed and validated a bioassay that yielded consistent and quantifiable CYVD symptoms on squash in the laboratory.

Differentially Regulates the Sexual Development and Pathogenicity of Plus and Minus Strains.

shows morphological and genetic differences in plus and minus strains. However, the mechanism of the differentiation between two types of strains is still largely unclear. Our early transcriptome analysis revealed that expression differed in plus and minus strains.

Changes in planta K nutrient content altered the interaction pattern between Nicotiana benthamiana and Alternaria longipes.

Potassium (K) fertilisation has frequently been shown to enhance plant resistance against pathogens, though the mechanisms remain elusive. This study investigates the interaction dynamics between Nicotiana benthamiana and the pathogen Alternaria longipes under different planta K levels. On the host side, adding K activated the expressions of three NLR (nucleotide-binding domain and leucine-rich repeat-containing proteins) resistance genes, including NbRPM1, NbR1B23 and NbNBS12.

First report of cucurbit yellow vine disease caused by on cucurbit crops in Iowa.

Cucurbit yellow vine disease (CYVD) is caused by , vectored by squash bugs (), and is an emerging disease in many parts of the U.S. CYVD can cause 100% yield losses in cucurbits (Bruton et al.

Cloning of maize chitinase 1 gene and its expression in genetically transformed rice to confer resistance against rice blast caused by Pyricularia oryzae.

Fungal pathogens are one of the major reasons for biotic stress on rice (Oryza sativa L.), causing severe productivity losses every year. Breeding for host resistance is a mainstay of rice disease management, but conventional development of commercial resistant varieties is often slow.

Regulates Pathogenicity and Sexual Development of Plus and Minus Strains in Causing Glomerella Leaf Spot on Apple in China.

is a devastating fungal pathogen of diverse plants. Sexually compatible plus and minus strains occur in the same ascus. However, the differentiation mechanism of plus and minus strains remains poorly understood.

Sufficient coumarin accumulation improves apple resistance to Cytospora mali under high-potassium status.

Cytospora canker, caused by Cytospora mali, is the most destructive disease in production of apples (Malus domestica). Adding potassium (K) to apple trees can effectively control this disease. However, the underlying mechanisms of apple resistance to C.

Guiding STEM graduate students to better speaking skills.

Training to enhance the effectiveness of oral presentations is often neglected in science, technology, engineering, and mathematics (STEM) fields. In this article, we summarize our experience of teaching a semester-long class in speaking skills to STEM graduate students and advocate for the critical importance of these skills to professional success.

First report of Fusarium sporotrichioides causing Fusarium fruit rot on peaches in Pakistan.

Peach (Prunus persica) is an important stone fruit crop cultivated on 14,350 hectares in temperate areas of Pakistan, where post-harvest fungal rots cause major economic losses for growers. During April-August 2019, rotted peaches were observed in fruit markets of Rawalpindi district (33° 37' 33.8052'' N and 73° 4' 17.

Diversity of Species Causing Apple Bitter Rot and Glomerella Leaf Spot in China.

Bitter rot and Glomerella leaf spot (GLS) of apples, caused by species, are major diseases of apples around the world. A total of 98 isolates were obtained from apple fruits with bitter rot, and 53 isolates were obtained from leaves with leaf spot in the primary apple production regions in China. These isolates were characterized morphologically, and five gene regions (, , , -1 and 2) were sequenced for each isolate.

The CfMcm1 Regulates Pathogenicity, Conidium Germination, and Sexual Development in .

Glomerella leaf spot (GLS), caused by , is a severe disease worldwide on apple, causing defoliation, leaf and fruit spot, and substantial yield loss. However, little is known about its molecular mechanisms of pathogenesis. Previous transcriptome analysis revealed that a transcription factor, CfMcm1, was induced during leaf infection.

Expression and Functional Analysis of the Type III Secretion System Effector Repertoire of the Xylem Pathogen on Cucurbits.

The predicted repertoire of type III secretion system effectors (T3SEs) in , causal agent of cucurbit bacterial wilt, is much larger than in xylem pathogens in the closely related genera and . The genomes of strains BHKY and SCR3, which represent distinct clades, encode at least 6 clade-specific and 12 shared T3SEs. The strains expressed the majority of the T3SE genes examined in planta.

First Report of Colletotrichum scovillei Causing Anthracnose on Watermelon (Citrullus lanatus) in Malaysia.

Production of watermelon (Citrullus lanatus) in Malaysia was 150,000 mt in 2020 (Malaysian Department of Agriculture, 2021). In November 2019, nine locally produced watermelon fruit (red flesh, seedless) from five local stores in the states of Kelantan, Terengganu, and Penang exhibited sunken, circular, brown lesions that enlarged to1.5 to 10 cm in diameter with scattered orange masses of conidia.

Sustainable Apple Disease Management in China: Challenges and Future Directions for a Transforming Industry.

Apple trees are grown worldwide, and consuming fresh apple fruit is associated with many health benefits. China produces about half of the world's apple supply. However, apple growing in China differs sharply from that in western countries in terms of the prevalent diseases and corresponding management strategies.

The Contributions to Virulence of the Effectors Eop1 and DspE Differ Between Two Clades of Strains.

Strains of causal agent of bacterial wilt of cucurbits, are divided into distinct clades. clade strains wilt spp. but not spp.

Characterization of Bacteriophage FBB1 Isolated from Spotted Cucumber Beetles that Vector .

the causal pathogen of bacterial wilt of cucurbit crops, is disseminated by cucumber beetles. A bacteriophage, designated FBB1 (u-eattie-eetle-1), was isolated from spotted cucumber beetles () that were collected from a field in which is endemic. FBB1 was classified into the family based on its morphology, which includes an elongated icosahedral head (106 × 82 nm) and a putatively contractile tail (120 nm).

Comparison of mitochondrial genomes provides insights into intron dynamics and evolution in Botryosphaeria dothidea and B. kuwatsukai.

Botryosphaeria dothidea is one of the most common fungal pathogens on a large number of hosts worldwide. Botryosphaeria dothidea and B. kuwatsukai are also the main causal agents of apple ring rot.

First Report of a Ceratocystis manginecans Causing Quick Decline of Psidium guajava in Pakistan.

Psidium guajava is a widely grown fruit tree of Asia for food and medicinal purposes. Also being reported to have anti-inflammatory, antimicrobial, antioxidant, antidiarrheal, antimutagenic properties (Somu, 2012). In April 2018, quick decline disease of guava was observed in orchards of Sheikhupura, Lahore, Faisalabad, Kasur and Chiniot districts of Punjab, Pakistan.

Sequence analysis of 16S rDNA, B and B genes of plant-associated species from Tunisia.

The genus contains several species with agricultural, biotechnological and ecological importance. Within this genus, many phyllosphere, rhizosphere and endosphere strains are plant growth promoting bacteria, whereas strains designated as are plant pathogens. In this study, we isolated 47 strains from a range of herbaceous and woody plant species.

Transcription Factor CfSte12 of Colletotrichum fructicola Is a Key Regulator of Early Apple Glomerella Leaf Spot Pathogenesis.

Glomerella leaf spot (GLS), caused by , is a rapidly emerging disease leading to defoliation, fruit spot, and storage fruit rot on apple in China. Little is known about the mechanisms of GLS pathogenesis. Early transcriptome analysis revealed that expression of the zinc finger transcription factor gene in () was upregulated in appressoria and leaf infection.

Performance and Profitability of Rain-Based Thresholds for Timing Fungicide Applications in Soybean Rust Control.

Soybean rust (SBR), caused by the fungus , is the most damaging disease of soybean in Brazil. Effective management is achieved by means of calendar-timed sprays of fungicide mixtures, which do not explicitly consider weather-associated disease risk. Two rain-based action thresholds of disease severity values (DSV50 and DSV80) were proposed and compared with two leaf wetness duration-temperature thresholds of daily values of infection probability (DVIP6 and DVIP9) and with a calendar program, with regard to performance and profitability.

Precipitation Impacts Dissemination of Three Sooty Blotch and Flyspeck Taxa on Apple Fruit.

The spatial dissemination of three prevalent taxa of sooty blotch and flyspeck (SBFS) fungi under several levels of precipitation was compared during 2015 and 2016 in an Iowa apple orchard. Overhead irrigation was used to supplement ambient precipitation in order to insure SBFS spore dissemination and colony development. There were five irrigation levels, involving 1-min-long periods of irrigation that were imposed either once or twice per hour at intervals of 3, 6, or 12 h, as well as a nonirrigated control.

A novel effector CfEC92 of Colletotrichum fructicola contributes to glomerella leaf spot virulence by suppressing plant defences at the early infection phase.

The ascomycete fungus Colletotrichum fructicola causes diseases on a broad range of plant species. On susceptible cultivars of apple, it induces severe early defoliation and fruit spots, named glomerella leaf spot (GLS), but the mechanisms of pathogenicity have remained elusive. Phytopathogens exhibit small secreted effectors to advance host infection by manipulating host immune reactions.

A Genome Sequence Resource for the Geographically Widespread Anthracnose Pathogen .

is a worldwide plant pathogen causing serious fruit or leaf anthracnose diseases on a variety of plant hosts such as mango, coffee berry, chili, and other potential hosts, and it is distributed widely in Asia, America, Africa, and Oceania. This is the first genome resource available for The draft genome assembly will allow further analysis of species diversity and evolutionary mechanisms, and may serve as a foundation for genetic analysis that leads to greater understanding of interactions between plants and fungal pathogens.