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N. benthamiana leaves were separately agroinfiltrated with infectious clones of LuYVVNV-HN, LuYVB-HN, and a mixture of both, to establish the pathogenicity of each viral strain. The inoculation of N. benthamiana plants with LuYVVNV-HN, either singularly or in combination with LuYVB-HN, demonstrated the characteristic symptoms of begomovirus infection. Seven days after inoculation (dpi), the emerging leaves showed a mild or severe curling downward, respectively, with a 100% infection rate (6/6) illustrated in Figure 1C. N. benthamiana plants inoculated with LuYVVNV-HN either independently or alongside LuYVB-HN displayed positive PCR results for the AV1 gene of LuYVVNV-HN. N. benthamiana plants simultaneously infected with LuYVVNV-HN and LuYVB-HN were the sole source of the C1 gene of LuYVB-HN, as evident in Figure 1D. Plants individually inoculated with LuYVB-HN exhibited no signs of viral infection, as evidenced by negative PCR results (Figure 1C and 1D). The findings indicated a successful inoculation of N. benthamiana plants with LuYVVNV-HN. Crucially, LuYVB-HN was shown to be incapable of independently initiating infections, instead acting as a helper, augmenting the viral pathogen’s capacity for causing disease. This report, for the first time, demonstrates the presence of LuYVVNV and LuYVB isolates within cigar tobacco, a crop with significant economic importance. The research results demonstrate the epidemic potential of begomovirus reservoirs in weeds, impacting nearby crop plants, and urge the importance of continuous monitoring and control of whitefly-transmitted diseases in global tobacco plantations (Ye et al., 2021).

In the Mediterranean, Orobanche crenata, a parasitic weed, is a significant deterrent to successful crop production. This bibliometric study evaluates the global research landscape and evolving trends in O. crenata, aiming to identify key research areas, development trends, and prominent contributors – authors, institutions, countries, and journals. A study encompassing 53 years (1968-2021) analyzed 274 articles pertinent to this field, drawn from the Scopus database, with the aid of VOSviewer and BiblioShiny software. Research indicates that 704% of all papers dedicated to O. crenata have been published in the last two decades. Research articles overwhelmingly focused on control methods, comprising 559% of the total. Weed Research journal’s impact on the field of weed research is undeniably the most significant. The countries that published the most articles were Spain, Egypt, and Italy. In terms of publication output in sustainable agriculture research, the Institute for Sustainable Agriculture was most heavily involved, contributing 317% of all papers; and Spanish authors demonstrated the highest productivity. Authors from Spain, Morocco, and Tunisia have been heavily involved in the recent five-year span of research literature, illustrating the persistence of this constraint in their respective countries. Keyword analysis highlighted vicia faba, germination, and legumes as the most prominent research areas. Despite the burgeoning collaborative spirit in this field, international cooperation falls short and should extend to nations recently afflicted by this scourge, allowing the sharing of expertise amassed by seasoned researchers and thus achieving more effective global control of this parasitic weed.

Classified within the Trichodoridae family, the plant-parasitic nematode species Paratrichodorus allius, a stubby root nematode, is of importance. Directly feeding on plant roots and indirectly transmitting Tobacco rattle virus, this organism causes harm to the plants. Either traditional microscopic methods or polymerase chain reaction (PCR) are the prevailing techniques for identifying these nematodes. The novel PCR technique, droplet digital PCR (ddPCR), excels in the sensitive and precise quantification of DNA templates within test samples. To identify and determine the quantity of P. allius in soil, a ddPCR assay was created during this investigation. Initial determination of the assay’s specificity and sensitivity involved employing P. allius nematode DNA or DNA extracted from soil sterilized and subsequently inoculated with P. allius. Subsequently, the assay quantified P. allius populations within field soils. Remarkably specific, the assay’s detection capabilities limited nematodes identified to P. allius alone. In soil DNA and nematode DNA extracts, a sensitivity of 0.001 and 0.002, respectively, parts per single nematode, enabled the detection of P. allius. DNA copy numbers from ddPCR exhibited a highly linear relationship with serial dilutions of known concentrations, as determined from P. allius nematodes (R² = 0.9842) and artificially infested soil samples (R² = 0.9464). The P. allius populations from field soil samples assessed by ddPCR displayed a high degree of correlation with the results from traditional microscopic counting (R² = 0.7963). To the best of our knowledge, this study represents the first use of ddPCR to evaluate and quantify the incidence of stubby root nematodes in soil. Diagnostic research on plant-parasitic nematodes suggests the ddPCR assay as a promising future tool.

Throughout Anhui, Hubei, Guizhou, Guangxi, Sichuan, Yunnan, and other provinces of China, the perennial plant Bletilla striata, part of the Orchidaceae family, is frequently encountered, as noted by He et al. (2017). Convergence, haemostasis, clearing away heat and toxins, reducing inflammation, and stimulating muscle growth are some of the effects of this treatment, according to He et al. (2017) and Xu et al. (2019). The cultivation of B. striata is a vital measure for maintaining the genetic resources of the species, especially with the reduced availability of wild specimens. Wang et al. (2022), Xu et al. (2022), and Zhou et al. (2022) all report occurrences of Fusarium root rot, leaf spot disease, and additional plant diseases on this plant in China. In Guizhou, Sichuan, and Hubei provinces of China, the presence of Coleosporium bletiae on B. striata has been reported, exhibiting frequent outbreaks and significant disease severity, particularly in Guizhou (Xu et al., 2022). In the Anhui Bletilla planting base, rust was discovered geographically positioned between 30.15°N and 30.77°N, and 115.75°E and 116.50°E, specifically during the months of April through November 2021. Supplementary figure S1 showcases the disease symptoms in approximately 17% of the B. striata plants. Associated with chlortic spots, 1-4 mm in width, on the upper leaf surface are hypophyllous, scattered, round, and powdery uredinia. Following mid-October, a gradual decline in temperature occurred, accompanied by the circular emergence of reddish-brown telia encircling uredinia. Sixty samples, exhibiting typical symptoms, were gathered. By means of sterile needles, urediospore and teliospore samples were collected, subsequently examined and measured under a microscope using sterile water. Predominantly oval-shaped urediospores, exhibiting an orange-yellow color, were uniformly covered with verrucae on the surface. Their dimensions were 272-368 µm by 176-228 µm (n=60) (Figure S2 a-b). Teliospores, characterised by a smooth, golden-yellow interior and a clavate shape narrowing from top to base, measured 8533-10966 µm × 1527-2035 µm (n=60). (Figures S2c-e). To facilitate genomic DNA extraction using the CTAB method (Xu et al., 2022), three samples, displaying typical symptoms, were chosen. Approximately 200 grams of urediospores per sample of the rust pathogen were collected and placed into 15-mL sterile centrifuge tubes. The internal transcribed spacer (ITS) region of rDNA was amplified by the ITS1/ITS4 primer pair, per Leclerc et al. (2000), while the large subunit (LSU) RNA genes were amplified with the NL1/NL4 primer pair, as described by Zhang et al. (2012). 100% identical and possessing 100% coverage, the obtained ITS (OP363678) and LSU (OP363683) sequences deposited in GenBank matched perfectly the ITS sequence MN108161 (Hubei) and the LSU sequence KX386038 from Coleosporium bletiae. The isolates, through a detailed examination of both their morphological characteristics and DNA sequence data, were concluded to represent C. bletiae (Figures S2 and S3). Healthy B. striata plants, two years old, were sprayed with 5 mL of urediospore suspension (26105 spores per milliliter) to determine their pathogenicity. A control group of plants was generated by spraying them with sterile distilled water. Within a controlled artificial climate incubator set at 25°C, a 12-hour light period alternating with a 12-hour dark period (90% relative humidity), the test was undertaken. Three instances of the experiment were repeated. Subsequent to two weeks of inoculation, the leaf surfaces displayed noticeable yellow chlorosis spots, along with a small number of yellow spore clusters on the leaves, which resembled the symptoms seen in the field (Figure S4). Control plants exhibited vigorous and healthy growth. The first report we are aware of, in Anhui province of China, involves C. bletiae causing rust on B. striata. Successful disease management strategies depend heavily on accurately identifying this condition to control its prevalence. Hubei and Anhui may experience the movement of seedlings and the spread of spores.

Over 1470 coffee growers, operating on approximately 10,000 acres across six Hawaiian islands, generate a coffee industry conservatively worth $100 million annually (USDA NASS 2023). pla pathway The unique status of Hawaii, as the world’s solitary major coffee-producing region untainted by Coffee Leaf Rust, held true until late October 2020. The arrival of Hemileia vastatrix Berk signifies the most formidable production predicament growers have encountered. In the coffee industry worldwide, Broome is the most economically damaging pathogen. Keith et al. (2022) documented the introduction of CLR, which has subsequently spread rapidly throughout the state, colonizing both coffee farms and wild coffee populations on each of the six islands.