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The western portion of the Pacific Northwest is known for being dry in the summer and cool and humid in the other months. Tall fescue is valued for its drought and heat tolerance, making it a desirable choice in regions where water is scarce and often restricted by legislation during periods of drought in the summer. However, cool and humid climates make it challenging to manage tall fescue in the winter because unacceptable quality is often observed due to low-temperature diseases and thinning in turf. A field trial was initiated in Autumn 2020 in Corvallis, OR, USA to assess the effects of mowing height as well as fertility timing and rate on tall fescue performance. Two mowing heights of 5.1 and 7.6 cm, four seasonal fertility timings, and three levels of annual N rates of 98, 196, and 294 kg·ha−1·yr−1 were evaluated using a 2 × 4 × 3 factorial experiment in a strip-plot design. Quantitative data of percent green cover and normalized difference vegetation index (NDVI) suggest that autumn fertilization is needed in cool, humid areas where tall fescue is actively growing in the winter months. The annual fertilization rate of 294 kg·ha−1·yr−1 N produced higher green turf cover and NDVI, compared with 98 or 196 kg·ha−1·yr−1 N. Furthermore, divergent effects of mowing heights were observed during winter compared with other months, suggesting that tall fescue could be mowed lower at 5.1 cm during cool, humid winter months and higher at 7.6 cm in other seasons for better overall turfgrass growth and less winter disease and thinning. Our research provides practical cultural practices for managing tall fescue turf in the Pacific Northwest or similar climates.

Drought stress, which often occurs repeatedly across the world, can cause multiple and long-term effects on plant growth. However, the repeated drought–rewatering effects on plant growth remain uncertain. This study was conducted to determine the effects of drought–rewatering cycles on aboveground growth and explore the underlying mechanisms. Perennial ryegrass plants were subjected to three watering regimes: well-watered control (W), two cycles of drought–rewatering (D2R), and one cycle of drought–rewatering (D1R). The results indicated that the D2R treatment increased the tiller number by 40.9% and accumulated 28.3% more aboveground biomass compared with W; whereas the D1R treatment reduced the tiller number by 23.9% and biomass by 42.2% compared to the W treatment. A time-course transcriptome analysis was performed using crown tissues obtained from plants under D2R and W treatments at 14, 17, 30, and 33 days (d). A total number of 2272 differentially expressed genes (DEGs) were identified. In addition, an in-depth weighted gene co-expression network analysis (WGCNA) was carried out to investigate the relationship between RNA-seq data and tiller number. The results indicated that DEGs were enriched in photosynthesis-related pathways and were further supported by chlorophyll content measurements. Moreover, tiller-development-related hub genes were identified in the D2R treatment, including F-box/LRR-repeat MAX2 homolog (D3), homeobox-leucine zipper protein HOX12-like (HOX12), and putative laccase-17 (LAC17). The consistency of RNA-seq and qRT-PCR data were validated by high Pearson’s correlation coefficients ranging from 0.899 to 0.998. This study can provide a new irrigation management strategy that might increase plant biomass with less water consumption. In addition, candidate photosynthesis and hub genes in regulating tiller growth may provide new insights for drought-resistant breeding.

Human papillomavirus (HPV) infection is the main cause of cervical cancer. HPV vaccination is considered an effective way to prevent cervical cancer. Although the vast majority of people experience no obvious adverse reactions after being vaccinated with HPV vaccine, the continuous monitoring of adverse events following immunization is important. Herein, we report the case of a previously healthy young woman who developed unilateral extraocular muscle palsy after receiving the third dose of the Gardasil HPV 9-valent vaccine (9vHPV) and was diagnosed with myasthenia gravis (MG). The patient developed swelling of the left eye on the 3rd day after vaccination and ptosis of the left eyelid on the 18th day after vaccination. She was treated with oral pyridostigmine and methylprednisolone. Her symptoms began to improve after 2 weeks of treatment and resolved completely after 3 weeks. After excluding other possible causes and considering the close temporal relationship between the timing of the 9vHPV vaccination and the onset of symptoms, 9vHPV appears to have triggered MG. To our knowledge, this is the first documented case report of 9vHPV-associated MG in China. Although ocular MG may be a rare adverse event after vaccination with 9vHPV, there is currently no direct evidence establishing a causal relationship; therefore, the safety of 9vHPV remains unquestioned.

Summary: In situ trace detection on ultra-clean surfaces is an important technology. The polyester fiber (PF) was introduced to serve as the template, to which the ionic liquids were bonded by hydrogen bonding. Polymerized ionic liquids (PIL) in PF were formed by in situ polymerization with the azodiisobutyronitrile (AIBN) and IL. The trace oil on metal surfaces was enriched by the composite membrane based on similar compatibility principle. The absolute recovery of the trace oil ranged from 91%–99% using this composite membrane. In the extraction samples, desirable linear correlations were obtained for trace oil in the range of 1.25–20 mg/mL. It has been proven that a 1 cm2 PIL-PF composite membrane can effectively extract as little as 1 mg of lubricating oil on an ultra-clean metal surface of 0.1 m2 with the LOD of 0.9 mg/mL, making it a promising material for in situ detection of trace oil on metal surfaces.

Anthracnose, caused by the fungal pathogen Colletotrichum cereale Manns sensu lato Crouch, Clarke & Hillman, can be a damaging disease on many cool-season turfgrasses; however, it has not been reported as an aggressive pathogen on fine fescue species (Festuca spp.). Symptoms and signs associated with anthracnose disease were observed in fine fescues on the Rutgers University Plant Science Research and Extension Farm in Adelphia, NJ, in Jun 2014. The objectives of this study were to identify the causal agent, determine if the isolate of C. cereale (FF1A) obtained from symptomatic Chewings fescue (Festuca rubra L. ssp. commutata Gaudin) plants was pathogenic to Chewings fescue and hard fescue (F. brevipila Tracey) turfs, and whether cultivars and accessions collected from Europe varied in disease susceptibility. Pathogenicity of this fine fescue isolate was evaluated using four Chewings fescue and four hard fescue cultivars or accessions in a growth chamber. Disease symptoms were first observed at 5 days post-inoculation, and evaluations continued to 17 days post-inoculation. Infection was confirmed by morphological evaluations, re-isolation from symptomatic tissues, and real-time polymerase chain reaction (PCR). Three noncommercial accessions (two Chewings fescues and one hard fescue) were very susceptible to the fine fescue C. cereale FF1A isolate, whereas ‘Sword’ and ‘Beacon’ hard fescues exhibited low susceptibility. In addition, an isolate of C. cereale (HF217CS) from annual bluegrass [Poa annua L. f. reptans (Hausskn) T. Koyama] was included, and our data demonstrated that this isolate was also able to infect Chewings fescue and hard fescue. This study confirmed that C. cereale can be a damaging pathogen of fine fescues, and that breeding for resistance to anthracnose should be considered when developing new cultivars.

Zoysia matrella is a salt-tolerant turfgrass grown in areas with high soil salinity irrigated with effluent water. Previous studies focused on explaining the regulatory mechanism of Z. matrella salt-tolerance at phenotypic and physiological levels. However, the molecular mechanism associated with salt tolerance of Z. matrella remained unclear. In this study, a high-efficient method named FOX (full-length cDNA overexpression) hunting system was used to search for salt-tolerant genes in Z. matrella. Eleven candidate genes, including several known or novel salt-tolerant genes involved in different metabolism pathways, were identified. These genes exhibited inducible expression under salt stress condition. Furthermore, a novel salt-inducible candidate gene ZmGnTL was transformed into Arabidopsis for functional analysis. ZmGnTL improved salt-tolerance through regulating ion homeostasis, reactive oxygen species scavenging, and osmotic adjustment. In summary, we demonstrated that FOX is a reliable system for discovering novel genes relevant to salt tolerance and several candidate genes were identified from Z. matrella that can assist molecular breeding for plant salt-tolerance improvement.

Abstract Sand size can affect the ability to incorporate topdressing into the turf canopy and thatch on golf course putting greens; unincorporated sand interferes with mowing and play. This 3-year field trial was initiated to determine the effects of sand size on sand incorporation, surface wetness, and anthracnose (caused by Colletotrichum cereale Manns sensu lato Crouch, Clarke, and Hillman) of annual bluegrass [Poa annua L. f. reptans (Hausskn) T. Koyama] maintained as a putting green. The experimental design was a randomized complete block with four replications; treatments included a non-topdressed control and three topdressing sands (medium-coarse, medium, or medium-fine) applied every 2 weeks at 0.15 L·m−2 during the summer. Topdressing with medium-coarse sand was more difficult to incorporate than the medium and medium-fine sands, resulting in a greater quantity of sand collected with mower clippings. Analyzing the particle distribution of sand removed by mowing confirmed that coarser sand particles were more likely to be removed in mower clippings. Surface wetness measured as volumetric water content (VWC) at the 0- to 38-mm depth zone was greater in non-topdressed plots than topdressed plots on 35% of observations. Few differences in VWC were found among sand size treatments. Turf responses to topdressing were not immediate; however, as sand accumulated in the turf canopy, topdressed plots typically had lower anthracnose severity than non-topdressed turf after the first year. Additionally, topdressing with medium and medium-fine sands produced similar or occasionally lower disease severity than topdressing with medium-coarse sand. The lack of negative effects of medium and medium-fine sands combined with better incorporation after topdressing and less disruption to the putting surface should allow golf course superintendents to apply topdressing at frequencies and/or quantities needed during the summer to maintain high-quality turf and playing conditions.

Plants are key components of the terrestrial ecosystem carbon cycle. Atmospheric CO2 is assimilated through photosynthesis and stored in plant biomass and in the soil. The use of turfgrass is expanding due to the increasing human population and urbanization. In this review, we summarize recent carbon sequestration research in turfgrass and compare turfgrass systems to other plant systems. The soil organic carbon (SOC) stored in turfgrass systems is comparable to that in other natural and agricultural systems. Turfgrass systems are generally carbon-neutral or carbon sinks, with the exception of intensively managed areas, such as golf course greens and athletic fields. Turfgrass used in other areas, such as golf course fairways and roughs, parks, and home lawns, has the potential to contribute to carbon sequestration if proper management practices are implemented. High management inputs can increase the biomass productivity of turfgrass but do not guarantee higher SOC compared to low management inputs. Additionally, choosing the appropriate turfgrass species that are well adapted to the local climate and tolerant to stresses can maximize CO2 assimilation and biomass productivity, although other factors, such as soil respiration, can considerably affect SOC. Future research is needed to document the complete carbon footprint, as well as to identify best management practices and appropriate turfgrass species to enhance carbon sequestration in turfgrass systems.

Extensive stolon development and growth are superior traits for rapid establishment as well as post-stress regeneration in stoloniferous grass species. Despite the importance of those stoloniferous traits, the regulation mechanisms of stolon growth and development are largely unknown. The objectives of this research were to elucidate the effects of the reallocation of soluble sugars for energy reserves and endogenous hormone levels for cell differentiation and regeneration in regulating stolon growth of a perennial turfgrass species, creeping bentgrass (Agrostis stolonifera L.). Plants were grown in growth chambers with two CO2 concentrations: ambient CO2 concentration (400 ± 10 µmol mol−1) and elevated CO2 concentration (800 ± 10 µmol mol−1). Elevated CO2 enhanced stolon growth through increasing stolon internode number and internode length in creeping bentgrass, as manifested by the longer total stolon length and greater shoot biomass. The content of glucose, sucrose, and fructose as well as endogenous IAA were accumulated in stolon nodes and internodes but not in leaves or roots under elevated CO2 concentration. These results illustrated that the production and reallocation of soluble sugars to stolons as well as the increased level of IAA in stolon nodes and internodes could contribute to the enhancement of stolon growth under elevated CO2 in creeping bentgrass.

Abstract Epichloë spp. are naturally occurring fungal endophytic symbionts of many cool-season grasses. Infection by the fungal endophytes often confers biotic and abiotic stress tolerance to their hosts. Endophyte-mediated disease resistance is well-established in the fine fescue grass Festuca rubra subsp. rubra (strong creeping red fescue) infected with E. festucae. Resistance to fungal pathogens is not an established effect of endophyte infection of other grass species, and may therefore be unique to the fine fescues. The underlying mechanism of the disease resistance is unknown. E. festucae produces a secreted antifungal protein that is highly expressed in the infected plant tissues and may therefore be involved in the disease resistance. Most Epichloë spp. do not have a gene for a similar antifungal protein. Here we report the characterization of the E. festucae antifungal protein, designated Efe-AfpA. The antifungal protein partially purified from the apoplastic proteins of endophyte-infected plant tissue and the recombinant protein expressed in the yeast Pichia pastoris was found to have activity against the important plant pathogen Sclerotinia homoeocarpa. Efe-AfpA may therefore be a component of the disease resistance seen in endophyte-infected strong creeping red fescue.

Strong creeping red fescue (Festuca rubra subsp. rubra) is a commercially important low-maintenance turfgrass and is often naturally infected with the fungal endophyte Epichloëfestucae. Epichloë spp. are endophytes of several cool-season grass species, often conferring insect resistance to the grass hosts due to the production of toxic alkaloids. In addition to insect resistance, a unique feature of the strong creeping red fescue/E. festucae symbiosis is the endophyte-mediated disease resistance to the fungal pathogen Clarireedia jacksonii, the causal agent of dollar spot disease. Such disease resistance is not a general feature of other grass/ Epichloë interactions. E. festucae isolates infecting red fescue have an antifungal protein gene Efe-afpA, whereas most other Epichloë spp. do not have a similar gene. The uniqueness of this gene suggests it may, therefore, be a component of the unique disease resistance seen in endophyte-infected red fescue. Here, we report the generation of CRISPR-Cas9 Efe-afpA gene knockouts with the goal of determining if absence of the protein in endophyte-infected Festuca rubra leads to disease susceptibility. However, it was not possible to infect plants with the knockout isolates, although infection was possible with the wild type E. festucae and with complemented isolates. This raises the interesting possibility that, in addition to having antifungal activity, the protein is required for the symbiotic interaction. The antifungal protein is a small secreted protein with high expression in planta relative to its expression in culture, all characteristics consistent with effector proteins. If Efe-AfpA is an effector protein it must be specific to certain interactions, since most Epichloë spp. do not have such a gene in their genomes.

The fungus Colletotrichum cereale incites anthracnose disease on Poa annua (annual bluegrass) turfgrass. Anthracnose disease is geographically widespread throughout the world and highly destructive to cool-season turfgrasses, with infections by C. cereale resulting in extensive turf loss. Comprehensive research aimed at controlling turfgrass anthracnose has been performed in the field, but knowledge of the causal organism and its basic biology is still needed. In particular, the lack of a reliable greenhouse-based inoculation protocol performed under controlled environmental conditions is an obstacle to the study of C. cereale and anthracnose disease. Our objective was to develop a consistent and reproducible inoculation protocol for the two major genetic lineages of C. cereale. By adapting previously successful field-based protocols and combining with components of existing inoculation procedures, the method we developed consistently produced C. cereale infection on two susceptible P. annua biotypes. Approximately 7 to 10 days post-inoculation, plants exhibited chlorosis and thinning consistent with anthracnose disease symptomology. Morphological inspection of inoculated plants revealed visual signs of the fungus (appressoria and acervuli), although acervuli were not always present. After stringent surface sterilization of inoculated host tissue, C. cereale was consistently re-isolated from symptomatic tissue. Real-time PCR detection analysis based on the Apn2 marker confirmed the presence of the pathogen in host tissue, with both lineages of C. cereale detected from all inoculated plants. When a humidifier was not used, no infection developed for any biotypes or fungal isolates tested. The inoculation protocol described here marks significant progress for in planta studies of C. cereale, and will enable scientifically reproducible investigations of the biology, infectivity and lifestyle of this important grass pathogen.

Microdochium patch is a turfgrass disease caused by the fungal pathogen Microdochium nivale (Fr.) Samuels and I.C. Hallett that occurs in climates similar to the cool, humid regions of North America's Pacific Northwest. Mineral oil, S, and phosphorous acid (H3PO3) have been shown to suppress Microdochium patch on annual bluegrass (Poa annua L.) putting greens in western Oregon. Previous research using rates of 19.9 kg mineral oil ha-1 applied every 2 wk alone or as a tank mixture with 12.2 kg S ha-1, 3.7 kg H3PO3 ha-1, or both resulted in unacceptable turfgrass thinning. The objective of this field experiment was to evaluate whether tank mixes of these products would suppress Microdochium patch and yield acceptable turfgrass quality when rates of mineral oil were reduced from 19.9 to 10.0 kg ha-1, S from 12.2 to 6.1 kg ha-1, or H3PO3 from 3.7 to 1.8 kg ha-1. In both years of the experiment, all treatments suppressed Microdochium patch to <2% disease compared to more than 40% disease in the non-treated control. Mineral oil applied with S resulted in a larger loss of green cover compared to mineral oil applied with H3PO3 regardless of rate. These results suggest that tank mixing mineral oil and S should be avoided in the winter months. Further research studying the mitigation of green cover loss associated with these treatments is warranted. [ABSTRACT FROM AUTHOR]

Increased N fertilization, mowing height, and sand topdressing are management practices that can suppress anthracnose disease of annual bluegrass [Poa annua L. f. reptans (Hausskn) T. Koyama; ABG] caused by Colletotrichum cereale Manns. A 3-yr field study evaluated the relative importance and interactions of these factors on anthracnose severity, turfgrass quality, and ball roll distance (BRD) on ABG turf in North Brunswick, NJ. A factorial combination of mowing height (2.3 and 3.2 mm), N fertilization (100 and 200 kg ha-1 yr-1), and sand topdressing (46 and 98 Mg ha-1 yr-1 in 2012; 37 and 81 Mg ha-1 yr-1 during 2013 and 2014) was arranged in a split-split-plot design with four replications. The practice of applying greater N fertilization (200 kg ha-1) provided the greatest reduction in disease severity and improvement in quality than the practices of higher mowing (3.2 mm) or greater sand topdressing (98 or 81 Mg ha-1). Combining greater N with higher mowing and greater sand topdressing provided acceptable disease suppression without the use of fungicides during moderate but not severe anthracnose epidemics. Higher mowing often produced unacceptable BRD (<2.9 m) especially when combined with greater N fertilization; whereas, under lower mowing, BRD was acceptable on most observation dates (91-96%) and less influenced by greater N fertilization. Thus, when adjustments in best practices for anthracnose management are needed to enhance BRD; lowering the mowing height will provide that enhancement while not greatly increasing the risk for anthracnose especially when greater N and increased topdressing practices are also employed. [ABSTRACT FROM AUTHOR]

In transportation process, normally there are several modes to deliver goods and sometimes there is crosstransportation or multimodal transport mode. Meanwhile, in the transportation process, transportation costs, time and risks vary with timeframe. Due to the characteristics of transportation network, transportation costs and transit time will vary with different starting time. Transportation costs can be divided into fixed costs, road transportation costs and transit fees considering multiple influence factors and various options, for instance, railway, airline and waterline. This article illustrates in detail that optimization of shortest path of multiple transportations based on cost analyses and this mode has been verified by genetic algorithm. [ABSTRACT FROM AUTHOR]