Morpho-Molecular and Ultrastructural Characterization of Discocriconemella Parasinensis n. Sp. from Zhejiang Province, China.

During a recent inventory survey of the nematofauna of tea plantation at Zhejiang Province, China, Discocriconemella parasinensis n. sp. was detected in the rhizosphere of Camellia sinensis. The new species can be characterized by having the uninterrupted rounded labial disc, en face view showing rectangular-rounded labial plate without submedian lobes, R = 82.6 (80-86), Rex = 22 (21-23), stylet length of 68.3 (59-76) µm, excretory pore located 1-2 annuli posterior to the esophageal bulb, vulva open, postvulval body elongated conoid, and tail conoid with bilobed terminus. Morphologically, the species shares the same lip-type with D. discolabia, D. mauritiensis, D. mineira, D. perseae, and D. sinensis. Phylogenetic relationships of the new species based on D2-D3 expansion segments of 28S, ITS, and 18S rRNA genes revealed that D. parasinensis n. sp. formed a separated clade from other criconematid species, thereby supporting its status as a new species of the genus. The new species showed close phylogenetic relationships with Criconemoides geraerti.

Rapid and Visual Detection of Heterodera schachtii Using Recombinase Polymerase Amplification Combined with Cas12a-Mediated Technology.

Heterodera schachtii is a well-known cyst nematode that causes serious economic losses in sugar beet production every year. Rapid and visual detection of H. schachtii is essential for more effective prevention and control. In this study, a species-specific recombinase polymerase amplification (RPA) primer was designed from a specific H. schachtii sequence-characterized amplified region (SCAR) marker. A band was obtained in reactions with DNA from H. schachtii, but absent from nontarget cyst nematodes. The RPA results could be observed by the naked eye, using a lateral flow dipstick (LFD). Moreover, we combined CRISPR technology with RPA to identify positive samples by fluorescence detection. Sensitivity analysis indicated that 10-4 single cysts and single females, 4-3 single second-stage juveniles, and a 0.001 ng genomic DNA template could be detected. The sensitivity of the RPA method for H. schachtii detection is not only higher than that of PCR and qPCR, but can also provide results in <1 h. Consequently, the RPA assay is a practical and useful diagnostic tool for early diagnosis of plant tissues infested by H. schachtii. Sugar beet nematodes were successfully detected in seven of 15 field sugar beet root samples using the RPA assay. These results were consistent with those achieved by conventional PCR, indicating 100% accuracy of the RPA assay in field samples. The RPA assay developed in the present study has the potential for use in the direct detection of H. schachtii infestation in the field.

Identification and Characterization of a Novel Protein Disulfide Isomerase Gene (MgPDI2) from Meloidogyne graminicola.

Protein disulfide isomerase (PDI) is a multifunctional enzyme that catalyzes rate-limiting reactions such as disulfide bond formation, isomerization, and reduction. There is some evidence that indicates that PDI is also involved in host-pathogen interactions in plants. In this study, we show that the rice root-knot nematode, Meloidogyne graminicola, has evolved a secreted effector, MgPDI2, which is expressed in the subventral esophageal glands and up-regulated during the early parasitic stage of M. graminicola. Purified recombinant MgPDI2 functions as an insulin disulfide reductase and protects plasmid DNA from nicking. As an effector, MgPDI2 contributes to nematode parasitism. Silencing of MgPDI2 by RNA interference in the pre-parasitic second-stage juveniles (J2s) reduced M. graminicola multiplication and also increased M. graminicola mortality under H2O2 stress. In addition, an Agrobacterium-mediated transient expression assay found that MgPDI2 caused noticeable cell death in Nicotiana benthamiana. An intact C-terminal region containing the first catalytic domain (a) with an active motif (Cys-Gly-His-Cys, CGHC) and the two non-active domains (b and b') is required for cell death induction in N. benthamiana. This research may provide a promising target for the development of new strategies to combat M. graminicola infections.

A new stunt nematode, Geocenamus chengi n. sp. (Nematoda: Merliniinae) in the rhizosphere of tea (Camellia sinensis) from Zhejiang Province, China.

The tea plant is native to China; the country has the greatest tea production areas in the world. In an attempt to investigate the nematode biodiversity associated with the tea plantations of Hangzhou, Zhejiang Province, a population of stunt nematode was detected. This group of nematodes is comprised of migratory ecto-parasites of roots and can subsist on a variety of host plants. Therefore, the detected population was studied carefully using the integrative taxonomy approach and identified as a new species of genus Geocenamus. Geocenamus chengi n. sp. can be characterized by females having six incisures in the lateral field; labial region is dome shaped and slightly offset from the rest of the body having four to five annuli; head framework is weakly developed; deirids are absent; excretory pore is located at the anterior region of basal pharyngeal bulb. Under SEM, the vulva is a transverse slit, vulval lips are elongated and ellipsoidal with epiptygma. The tail is annulated, elongated, and conical having bluntly pointed tip and a terminal hyaline region that forms 21 to 33% of the tail length. Spicule is 22 to 25 µm long, gubernaculum is saucer shaped; bursa is crenated covering the tail until the hyaline tail region. Morphologically, the species is close to G. circellus, G. joctus, G. loofi, G. ordinarius, G. processus, G. tetyllus, and G. tortilis. Phylogenetic relationships of the new species based on D2-D3 expansion domains of 28 S, ITS, and 18 S rRNA genes indicated that G. chengi n. sp. clustered in a separate clade with G. vietnamensis.The tea plant is native to China; the country has the greatest tea production areas in the world. In an attempt to investigate the nematode biodiversity associated with the tea plantations of Hangzhou, Zhejiang Province, a population of stunt nematode was detected. This group of nematodes is comprised of migratory ecto-parasites of roots and can subsist on a variety of host plants. Therefore, the detected population was studied carefully using the integrative taxonomy approach and identified as a new species of genus Geocenamus. Geocenamus chengi n. sp. can be characterized by females having six incisures in the lateral field; labial region is dome shaped and slightly offset from the rest of the body having four to five annuli; head framework is weakly developed; deirids are absent; excretory pore is located at the anterior region of basal pharyngeal bulb. Under SEM, the vulva is a transverse slit, vulval lips are elongated and ellipsoidal with epiptygma. The tail is annulated, elongated, and conical having bluntly pointed tip and a terminal hyaline region that forms 21 to 33% of the tail length. Spicule is 22 to 25 µm long, gubernaculum is saucer shaped; bursa is crenated covering the tail until the hyaline tail region. Morphologically, the species is close to G. circellus, G. joctus, G. loofi, G. ordinarius, G. processus, G. tetyllus, and G. tortilis. Phylogenetic relationships of the new species based on D2-D3 expansion domains of 28 S, ITS, and 18 S rRNA genes indicated that G. chengi n. sp. clustered in a separate clade with G. vietnamensis.

A new rare nematode Nothocriconemoides hangzhouensis n. sp. (Nematoda: Criconematidae) from Hangzhou, China.

The Family Criconematidae is commonly referred as ring nematodes that include some members with economic importance as plant parasites. During a recent nematode inventory survey at Zhejiang Province, China, a new species of genus Nothocriconemoides was detected in the rhizosphere of elm tree. Nothocriconemoides hangzhouensis n. sp. can be characterized by the female body having annuli with fine longitudinal striations and 2 to 3 anastomoses at the posterior half of the body. The first cephalic annulus is rounded and expanded enclosing the lip region, and the second annulus is narrow, offset, collar like. En face view shows a central elevated labial disk bearing four distinct equal-sized submedian lobes and "I" shaped oral aperture. Excretory pore is located 3-4 annuli posterior to esophageal bulb. Vagina is straight and vulva closed. The ventral side of postvulval annuli is inverted, in majority of individuals. Anus is indistinct and located on the next annuli posterior to vulva. Tail is short, conoid, with forked or branched terminus. Juveniles are devoid of collar-shaped annuli in the lip region. The cephalic region has two rounded annuli where the first annulus shows slight depression in the middle. Body annuli are finely crenated. Anus is indistinct and located 3 to 4 annuli from tail terminus. Tail is short ending in a single lobed terminus. Phylogenetic studies based on analysis of the D2-D3 expansion segments of the 28 S rRNA, ITS rRNA, partial 18 S rRNA, and coxI gene revealed that the new species formed a separate clade from other criconematid species, thereby supporting its status as a new species of the genus. The new species showed close relationships with Discocriconemella sinensis. Additionally, this is the first record of genus Nothocriconemoides from China.The Family Criconematidae is commonly referred as ring nematodes that include some members with economic importance as plant parasites. During a recent nematode inventory survey at Zhejiang Province, China, a new species of genus Nothocriconemoides was detected in the rhizosphere of elm tree. Nothocriconemoides hangzhouensis n. sp. can be characterized by the female body having annuli with fine longitudinal striations and 2 to 3 anastomoses at the posterior half of the body. The first cephalic annulus is rounded and expanded enclosing the lip region, and the second annulus is narrow, offset, collar like. En face view shows a central elevated labial disk bearing four distinct equal-sized submedian lobes and "I" shaped oral aperture. Excretory pore is located 3­4 annuli posterior to esophageal bulb. Vagina is straight and vulva closed. The ventral side of postvulval annuli is inverted, in majority of individuals. Anus is indistinct and located on the next annuli posterior to vulva. Tail is short, conoid, with forked or branched terminus. Juveniles are devoid of collar-shaped annuli in the lip region. The cephalic region has two rounded annuli where the first annulus shows slight depression in the middle. Body annuli are finely crenated. Anus is indistinct and located 3 to 4 annuli from tail terminus. Tail is short ending in a single lobed terminus. Phylogenetic studies based on analysis of the D2­D3 expansion segments of the 28 S rRNA, ITS rRNA, partial 18 S rRNA, and coxI gene revealed that the new species formed a separate clade from other criconematid species, thereby supporting its status as a new species of the genus. The new species showed close relationships with Discocriconemella sinensis. Additionally, this is the first record of genus Nothocriconemoides from China.

Updated description of Paratylenchus lepidus Raski 1975 and P. minor Sharma, Sharma and Khan, 1986 by integrating molecular and ultra-structural observations.

Two populations of Paratylenchus lepidus and P. minor were detected in the rhizosphere of Elaeocarpus sp. and Chinese red pine from Taizhou and Hangzhou, Zhejiang Province, China. Previously, P. lepidus has been reported from China whereas P. minor was originally described from India decades ago in the rhizosphere of peach but was never reported thereafter. In this study, both species were characterized morphologically and molecularly coupled with SEM observations. Morphologically, both species have four incisures in the lateral field, vulval present (SEM observations), stylet less than 30 µm long and cephalic region without submedian lobes. Phylogenetically, both species grouped with paratylenchid species having short stylets. Both species can be differentiated from each other by the shape of lip region (rounded in P. lepidus and narrow truncated in P. minor) and tail terminus (pointed in P. lepidus and a broadly rounded in P. minor) and several morphomemtrical values.The study provided an updated description of P. lepidus and P. minor and a first record of P. minor from China. In addition, both species are the first paratylenchid species recorded from Elaeocarpus sp. and Pinus tabuliformis, respectively.

Integrative taxonomy of Xiphinema histriae and Xiphinema lapidosum from Spain.

Three populations of Xiphinema non-americanum group species were detected in agricultural and natural ecosystems, during routine surveys for plant-parasitic nematodes in Spain. Based on morphological and molecular analyses, the species were identified as Xiphinema histriae and Xiphinema lapidosum, being this the first record and molecular characterization of both species in Spain. The morphometrics and morphology of the Spanish populations agree with those of the original description and paratype specimens and the present study provided a first description of the second to fourth juvenile stages of both species. A detailed study on the morphology in the Spanish populations of X. histriae, as well as in paratypes, showed a pseudo-Z-organ with weakly muscularized wall and containing numerous small dense granular bodies, which was different to the original description by Lamberti et al. (1993). This new finding suggests that X. histriae must be considered a member of the morphospecies Group 5 of X. non-americanum. Phylogenetic analysis based on D2 to D3 expansion segments of 28S gene, ITS1 and partial CoxI gene indicated that X. histriae and X. lapidosum are phylogenetically related with other Xiphinema non-americanum group spp. reported from Spain. Considering the pathological and economic importance of this group of nematodes, the combination of morphological characters, measurements, and molecular analysis is crucial for accurate identification of these species.

Morphological and Molecular Characterization of Paralongidorus sali Siddiqi, Hooper, and Khan, 1963 with a Description of the First-Stage Juvenile and Male of Longidorus jonesi Siddiqi, 1962 from China.

Longidorids are economically important plant-parasitic nematodes because several species are virus vectors. Populations of Paralongidorus sali and Longidorus jonesi , isolated from woody perennials of Hangzhou, Zhejiang, China, were characterized molecularly and morphologically. The morphometric data of the Chinese populations of both species were compared with other populations. The present study provided a first record of the occurrence of Paralongidorus in China coupled with description of the first-stage Juvenile and male of L. jonesi . Phylogenetic analysis based on 18S and D2-D3 expansion segments of 28S gene indicated that L. jonesi clustered with L. jonesi reported from Japan and P. sali grouped with P. bikanerensis from Iran. Considering the pathological and economic importance of this group of nematodes, the study emphasized the need of updated descriptions from accurately identified specimens, isolation of sufficient material for examination, and molecular and phylogenetic analysis for a better understanding and diagnostics of Longidorid nematodes.

Description of Gracilacus paralatescens n. sp. (Nematoda:Paratylenchinae) found from the rhizosphere of Bamboo in Zhejiang, China.

Gracilacus paralatescens n. sp., isolated in Anji County, Zhejiang Province, China from the rhizospheric soil of bamboo. The new species can be characterized by the female lateral field with three incisures, stylet 71.5 to 78.8 µm long, lip region truncated, excretory pore located anterior to basal knobs. Vulval lips non-protruding and without vulval flap, spermatheca large, elongated squarish shaped filled with sperms. Tail slender, relatively straight having wedge shape terminus. The spicule slender, slightly curved and 17.5 to 18.9 µm long. In the phylogenetic analysis based on 18S, D2-D3 of 28S and ITS regions of rDNA, the new species is clustered with Paratylenchid species having longer stylet length. Morphologically, the new species belongs to Group 9 of Paratylenchus sensu lato and is most similar to G. latescens.Gracilacus paralatescens n. sp., isolated in Anji County, Zhejiang Province, China from the rhizospheric soil of bamboo. The new species can be characterized by the female lateral field with three incisures, stylet 71.5 to 78.8 µm long, lip region truncated, excretory pore located anterior to basal knobs. Vulval lips non-protruding and without vulval flap, spermatheca large, elongated squarish shaped filled with sperms. Tail slender, relatively straight having wedge shape terminus. The spicule slender, slightly curved and 17.5 to 18.9 µm long. In the phylogenetic analysis based on 18S, D2-D3 of 28S and ITS regions of rDNA, the new species is clustered with Paratylenchid species having longer stylet length. Morphologically, the new species belongs to Group 9 of Paratylenchus sensu lato and is most similar to G. latescens.

Description and Distribution of Three Criconematid Nematodes from Hangzhou, Zhejiang Province, China.

Populations of Criconemoides parvus , Discocriconemella hengsungica , and Discocriconemella limitanea , isolated in Hangzhou, China from the rhizosphere soil of woody perennials were characterized morphologically and molecularly. The morphometric data of the Chinese populations were compared with populations from other regions of the world. DNA barcoding with the mitochondrial COI gene confirmed conspecificity of Chinese and Costa Rican populations of D. limitanea . Phylogenetic assessment using a near full-length 18S ribosomal DNA sequence provided weak support for a grouping of Criconemoides parvus from China and C. annulatus from western North America. The phylogenetic position of D. hengsungica from China and an unknown species of Discocriconemella from Thailand relative to D. limitanea suggests that the genus Discocriconemella is not monophyletic. The study provides the first record of D. hengsungica in China and confirms the presence of C. parvus previously reported from China. Biogeographic implications of these nematode distributions are discussed.

Genomic identification of nitrogen-fixing Klebsiella variicola, K. pneumoniae and K. quasipneumoniae.

It was difficult to differentiate Klebsiella pneumoniae, K. quasipneumoniae and K. variicola by biochemical and phenotypic tests. Genomics increase the resolution and credibility of taxonomy for closely-related species. Here, we obtained the complete genome sequence of the K. variicola type strain DSM 15968(T) (=F2R9(T)). The genome of the type strain is a circular chromosome of 5,521,203 bp with 57.56% GC content. From 540 Klebsiella strains whose genomes had been publicly available as at 3 March 2015, we identified 21 strains belonging to K. variicola and 8 strains belonging to K. quasipneumoniae based on the genome average nucleotide identities (ANI). All the K. variicola strains, one K. pneumoniae strain and five K. quasipneumoniae strains contained nitrogen-fixing genes. A phylogenomic analysis showed clear species demarcations for these nitrogen-fixing bacteria. In accordance with the key biochemical characteristics of K. variicola, the idnO gene encoding 5-keto-D-gluconate 5-reductase for utilization of 5-keto-D-gluconate and the sorCDFBAME operon for catabolism of L-sorbose were present whereas the rbtRDKT operon for catabolism of adonitol was absent in the genomes of K. variicola strains. Therefore, the genomic analyses supported the ANI-based species delineation; the genome sequence of the K. variicola type strain provides the reference genome for genomic identification of K. variicola, which is a nitrogen-fixing species.

Potential of Pseudomonas chlororaphis subsp. aurantiaca Strain Pcho10 as a Biocontrol Agent Against Fusarium graminearum.

To develop an effective biocontrol strategy for management of Fusarium head blight on wheat caused by Fusarium graminearum, the bacterial biocontrol agent Pcho10 was selected from more than 1,476 wheat-head-associated bacterial strains according to its antagonistic activity in vitro. This strain was subsequently characterized as Pseudomonas chlororaphis subsp. aurantiaca based on 16S ribosomal DNA sequence analysis, assays of the BIOLOG microbial identification system, and unique pigment production. The major antifungal metabolite produced by Pcho10 was further identified as phenazine-1-carboxamide (PCN) on the basis of nuclear magnetic resonance data. The core PCN biosynthesis gene cluster in Pcho10 was cloned and sequenced. PCN showed strong inhibitory activity against F. graminearum conidial germination, mycelial growth, and deoxynivalenol production. Tests both under growth chamber conditions and in field trials showed that Pcho10 well colonized on the wheat head and effectively controlled the disease caused by F. graminearum. Results of this study indicate that P. chlororaphis subsp. aurantiaca Pcho10 has high potential to be developed as a biocontrol agent against F. graminearum. To our knowledge, this is the first report of the use of P. chlororaphis for the management of Fusarium head blight.

Scalable and Flexible Multi-Layer Prismatic Photonic Metamaterial Film for Efficient Daytime Radiative Cooling.

To maintain a comfortable indoor living environment in low latitude or tropical regions, humans consume significant amounts of electrical energy in air conditioning, leading to substantial CO2 emissions. Passive daytime radiative cooling (PDRC) allows objects to cool down during the daytime without any energy consumption by dissipating heat through the atmospheric transparency window (8-13 µm) to outer space, which has garnered significant attention. However, the practical applications of common PDRC materials are hindered by their poor optical selectivity and high-reflective silver backing. Additionally, the availability of artificial photon emitters with complex structures and excellent performance is also limited by their high cost. Herein, a novel multilayer prismatic photonic metamaterial film without any silver reflector, easily scalable and produced by a roll-to-roll method is demonstrated, which exhibits ≈96.4% sunlight reflectance (0.3-2.5 µm) and ≈97.2% emissivity in mid-infrared (IR) (8-13 µm). At an average solar intensity of ≈920 W m-2, it is on average 6.8 °C below ambient temperature during the day and theoretically yields a radiative cooling power of 88.9 W m-2. Furthermore, the film exhibits excellent hydrophobicity, superior flexibility, and robust mechanical strength, providing an attractive and viable pathway for practical applications addressing the pressing challenges of climate and energy issues.

Intraparticle Electron Transfer for Long-Lasting Tumor Chemodynamic Therapy.

Chemodynamic therapy (CDT) is a novel tumor treatment method by using hydroxyl radicals (•OH) to kill cancer cells. However, its therapeutic effects are strictly confined by the short lifespan of •OH and reduced •OH generation speed. Herein, an effective CDT is achieved by both improving •OH lifetime and long-lasting generating •OH through intraparticle electron transfer within heterogeneous nanoparticles (NPs). These heterogeneous NPs are composed of evenly distributed Cu and Fe3O4 (CFO NPs) with large interaction interfaces, and electrons tend to transfer from Cu to Fe3O4 for the appearance of ≡Cu2+ and increase in ≡Fe2+. The generated ≡Cu2+ can interact with GSH, which prolongs the lifespan of •OH, produces ≡Cu+ for higher speed •OH generation with H2O2, and induces cell ferroptosis for tumor therapy. The improved ≡Fe2+ can also improve the •OH release under H2O2 until Cu is depleted. As a result, a sustainable •OH generation is achieved to promote cell apoptosis for effective tumor therapy. Since H2O2 and GSH are only overexpressed at tumor, and CFO NPs can degrade in the tumor microenvironment, these NPs are with high biosafety and can be metabolized by urine. This work provides a novel biomaterial for effective cancer CDT through intraparticle electron transfer.

Preparation of Densified Fine-Grain High-Frequency MnZn Ferrite Using the Cold Sintering Process.

The densified MnZn ferrite ceramics were prepared using the cold sintering process under pressure, with an acetate ethanol solution used as the transient solvent. The effects of the transient solvent, the pressure and annealing temperature on the density, and the micromorphology and magnetic properties of the sintered MnZn ferrites were studied. The densified MnZn ferrite was obtained using the cold sintering process and its relative density reached up to 85.4%. The transient solvent and high pressure are essential to the cold sintering process for MnZn ferrite. The annealing treatment is indispensable in obtaining the sample with the higher density. The relative density was further increased to 97.2% for the sample annealed at 950 °C for 6 h. The increase in the annealing temperature reduces the power loss at high frequencies.

Self-Monitoring Theranostic Nanomaterials: Emerging Visual Agents for Real-Time Monitoring of Tumor Treatment Processes.

Self-monitoring in tumor therapy is a concept that allows for real-time monitoring of the location and state of applied nanomaterials. This monitoring relies on dynamic signals, such as wave or magnetic signals, which vary in response to changes in the location and state of nanomaterials. Dynamic changes in nanomaterials can be monitored using dynamic signals, making it possible to determine and control the treatment process. Theranostic nanomaterials, which possess unique physical and chemical properties, have recently been explored as a viable option for self-monitoring. With the help of self-monitoring, theranostic nanomaterials can guide themselves to achieve region-selective treatment with higher controllability and safety. In this review, self-monitoring theranostic nanomaterials will be introduced in three parts according to their roles during therapy: tumor accumulation, tumor therapy, and metabolism. The limitations and future challenges of current self-monitoring theranostic nanomaterials will also be discussed.

Redox Homeostasis Disruptors Based on Metal-Phenolic Network Nanoparticles for Chemo/Chemodynamic Synergistic Tumor Therapy through Activating Apoptosis and Cuproptosis.

The combination of chemo/chemodynamic therapy is a promising strategy for improving antitumor efficacy. Herein, metal-phenolic network nanoparticles (NPs) self-assembled from copper ions and gallic acid (Cu-GA) are developed to evoke apoptosis and cuproptosis for synergistic chemo/chemodynamic therapy. The Cu-GA NPs are biodegraded in response to the highly expressed glutathione (GSH) in tumor cells, resulting in the simultaneous release of Cu+ and GA. The intracellular GSH content is dramatically reduced by the released GA, rendering the tumor cells incapable of scavenging reactive oxygen species (ROS) and more susceptible to cuproptosis. Meanwhile, ROS levels within the tumor cells are significantly increased by the Fenton-like reaction of released Cu+ , which disrupts redox homeostasis and achieves apoptosis-related chemodynamic therapy. Moreover, massive accumulation of Cu+ in the tumor cells further induces aggregation of lipoylated dihydrolipoamide S-acetyltransferase and downregulation of iron-sulfur cluster protein, activating cuproptosis to enhance the antitumor efficacy of Cu-GA NPs. The experiments in vivo further demonstrate that Cu-GA NPs exhibited the excellent biosafety and superior antitumor capacity, which can efficiently inhibit the growth of tumors due to the activation by the tumor specific GSH and hydrogen peroxide. These Cu-based metal-phenolic network NPs provide a potential strategy to build up efficient and safe cancer therapy.

Morphological and molecular characterization of Geocenamus persici n. sp. (Nematoda: Merliniinae) from China.

A new stunt nematode species, Geocenamus persici n. sp. was recovered from the rhizosphere of peach (Prunus persica) in Zhejiang Province, China. This species is characterized by a dome-shaped labial region with six bulging sectors. The lip region is slightly offset from the rest of the body with five annuli; cuticle with over 30 longitudinal striae; stylet slender, 19 to 21 m long; excretory pore at the anterior region of the basal pharyngeal bulb; tail cylindrical, 55 to 79 m long with striated terminus. Males are common. Morphologically, the species is close to G. brevicaudatus, G. chengi, G. conicaudatus, G. quadrifer, G. rugosus, and G. tartuensis. Phylogenetic relationships of the new species placed G. persici n. sp. with other species of subfamily Merliniinae. However, it has a sister relationship with G. chengi. Since the new species is found in the peach plantations, our study will lay a foundation to initiate investigations on the occurrence of stunt nematodes in peach growing areas and will aid the researchers to determine whether this group of nematodes cause peach plantation diseases.

Shoot rot of Zizania latifolia and the first record of its pathogen Pantoea ananatis in China.

The aquatic grass Zizania latifolia grows symbiotically with the fungus Ustilago esculenta producing swollen structures called Jiaobai, widely cultivated in China. A new disease of Z. latifolia was found in Zhejiang Province, China. Initial lesions appeared on the leaf sheaths or sometimes on the leaves near the leaf sheaths. The lesions extended along the axis of the leaf shoots and formed long brown to dark brown streaks from the leaf sheath to the leaf, causing sheath rot and death of entire leaves on young plants. The pathogen was isolated and identified as the bacterium Pantoea ananatis, based on 16S ribosomal RNA (rRNA) gene sequencing, multilocus sequence analysis (atpD (ß-subunit of ATP synthase F1), gyrB (DNA gyrase subunit B), infB (translation initiation factor 2), and rpoB (ß|-subunit of RNA polymerase) genes), and pathogenicity tests. Ultrastructural observations using scanning electron microscopy revealed that the bacterial cells colonized the vascular tissues in leaf sheaths, forming biofilms on the inner surface of vessel walls, and extended between vessel elements via the perforated plates. To achieve efficient detection and diagnosis of P. ananatis, species-specific primer pairs were designed and validated by testing closely related and unrelated species and diseased tissues of Z. latifolia. This is the first report of bacterial sheath rot disease of Z. latifolia caused by P. ananatis in China.

Injection Molding and Sintering of ZrO2 Ceramic Powder Modified by a Zirconate Coupling Agent.

Ceramic injection molding is a near-net shape-processing technique, producing ceramic components with low tooling costs and complex shapes. In this paper, ZrO2 ceramics with high loading content in the green part were prepared by powder modification using zirconate coupling agent, injection molding and sintering, which benefited decreasing the usage of binders and deformation of ceramics. The rheological characteristics of feedstocks, densities, microstructures and mechanical properties of green and sintered parts with the different coupling media and sintering temperatures were studied. The results showed that the addition of a zirconate coupling agent with ethanol medium obviously increased the flowability of feedstocks and benefited achieving the green parts with high powder loading (86.5 wt.%) and bending strength (12.9 MPa) and the final unbroken ceramics. In addition, the sintering temperatures from 1500-1575 °C had no significant effects on the density, hardness, and surface morphology of the ceramic samples. However, the bending strength increased and some large grains with transgranular fracture occurred on the fractural surface at the sintering temperature of 1575 °C.