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Please wait a minute... For Selected: Download Citations EndNote Ris BibTeX Toggle Thumbnails Select Molecular Characterization and Functional Analysis of a New Acid Phosphatase Gene (Ha-acp1) from Heterodera avenae LIU Yan-ke, HUANG Wen-kun, LONG Hai-bo, PENG Huan, HE Wen-ting , PENG De-liang 2014, 13 (6): 1303-1310.   DOI: 10.1016/S2095-3119(13)60536-5 Abstract （1699）      PDF in ScienceDirect       For sedentary endo-parasitic nematodes, parasitism genes encoding secretory protein expressed in the subventral glands cells always play an important role during the early parasitic process. A new acid phosphatase gene (Ha-acp1) expressed in the subventral glands of the cereal cyst nematode (Heterodera avenae) was cloned and the characteristics of the gene were analyzed. Results showed that the gene had a putative signal peptide for secretion and in situ hybridization showed that the transcripts of Ha-acp1 accumulated specifically in the subventral gland cells of H. avenae. Southern blot analysis suggested that Ha-acp1 belonged to a multigene family. RT-PCR analysis indicated that this transcription was strong at the pre-parasitic juveniles. Knocking down Ha-acp1 using RNA interference technology could reduce nematode infectivity by 50%, and suppress the development of cyst. Results indicated that Ha-acp1 could play an important role in destroying the defense system of host plants. Reference | Related Articles | Metrics Select A new pathotype characterization of Daxing and Huangyuan populations of cereal cyst nematode (Heterodera avenae) in China CUI Jiang-kuan, HUANG Wen-kun, PENG Huan, LIU Shi-ming, WANG Gao-feng, KONG Lin-an, PENG De-liang 2015, 14 (4): 724-731.   DOI: 10.1016/S2095-3119(14)60982-5 Abstract （2052）      PDF in ScienceDirect       The cereal cyst nematode (CCN, Heteroder aavenae) causes serious yield loss on cereal crops, especially wheat, worldwide. Daxing population in Beijing City and Huangyuan population in Qinghai Province, China, are two CCN populations. In this study, the CCN pathotypes of Daxing and Huangyuan populations were characterized by tests on 23 standard “International Test Assortment” with the local species Wenmai 19 as the susceptible control. Tested materials were grouped by three nematode populations’ virulence on resistant genes (Rha1, Rha2, Rha3, Cre1) and nonresistant genes, varieties and lines. Both Daxing and Huangyuan populations were avirulent to Ortolan (Ha1). Barley cvs. Ortolan, Siri, Morocco, Bajo Aragon 1-1, and Martin 403-2 were all resistant to both populations. Cultivars Herta, Harlan 43 and wheat Iskamish-K-2-light were all susceptible to Huangyuan population, all of them, however, were resistant to Daxing population. The other five oats were all resistant to the two tested CCN populations. Except Iskamisch K-2-light, all the other wheat cultivars (Capa, Loros×Koga, AUS 10894, and Psathias) were susceptible to Daxing population. Because the pathotypes of the two tested CCN populations in Beijing and Qinghai were not identical to any of the 13 pathotypes previously characterized by the test assortment, we classified Daxing and Huangyuan populations as the new pathotypes, named Ha91. Reference | Related Articles | Metrics Select Parasitism and pathogenicity of Radopholus similis to Ipomoea aquatica, Basella rubra and Cucurbita moschata and genetic diversity of different populations LI Yu, WANG Ke, XIE Hui, XU Chun-ling, WANG Dong-wei, LI Jing, HUANG Xin, PENG Xiao-fang 2016, 15 (1): 120-134.   DOI: 10.1016/S2095-3119(14)61003-0 Abstract （2006）      PDF in ScienceDirect       Ten populations of Radopholus similis from different ornamental hosts were tested for their parasitism and pathogenicity to water spinach (Ipomoea aquatic), malabar spinach (Basella rubra), and squash (Cucurbita moschata) in pots. The results showed all three plants were new hosts of R. similis. Growth parameters of plants inoculated with nematodes were significantly lower than those of healthy control plants. All R. similis populations were pathogenic to the three plants, but pathogenicity differed among populations from different hosts. The same R. similis populations also showed different pathogenic effects in the three different plants. RadN5 population from Anthurium andraeanum had the highest pathogenicity to the three studied plants. RadN1 from A. andraeanum had the lowest pathogenicity to squash and RadN7 from Chrysalidocarpus lutesens had the lowest pathogenicity to water spinach and malabar spinach. R. similis is usually associated with root tissues, but here we report that it could be found to move and feed in the stem bases of all three studied plants. Sequence and phylogenetic analyses of DNA markers of the 18S rRNA, 28S rRNA, ITS rRNA, and mitochondrial DNA gene sequences of ten R. similis populations revealed significant genetic diversity. RadN5 and RadN6 populations from anthurium showed a close genetic relationship and could be distinguished from other populations by PCR-RFLP. At the same time, RadN5 and RadN6 populations were the most pathogenic to three studied plants. These results confirm the existence of large biological variability and molecular diversity among R. similis populations from the same or different hosts, and these characteristics are related to pathogenic variability. Reference | Related Articles | Metrics Select Assaying the potential of twenty-one legume plants in Medicago truncatula and M. sativa for candidate model plants for investigation the interactions with Heterodera glycines KONG Ling-an, WU Du-qing, HUANG Wen-kun, PENG Huan, HE Wen-ting, PENG De-liang 2016, 15 (3): 702-704.   DOI: 10.1016/S2095-3119(15)61156-X Abstract （1620）      PDF in ScienceDirect       Soybean cyst nematode Heterodera glycines is one of the most serious soil-borne pathogens in soybean production. However, the researches were limited in China due to lack of an effective pathosystem. In this study, we screened 21 legume Medicago plants in both Medicago truncatula and Medicago sativa to obtain candidate model plants for establishing a new pathosystem for legume-H. glycines interactions. The nematode infection of tested plants was assayed with Race 3 and 4 respectively, which were two dominant H. glycines inbred races in China soybean producing areas. The results showed that the model legume plant M. truncatula A17 failed to allow Race 3 of H. glycines to complete its life cycle, in contrast, it provided the Race 4 population to form several cyst nematodes, however, the female index (FI) value was approximately 1.6. Three M. sativa cultivars, including Xunlu, Aergangjin and Junren, provided either Race 3 or 4 of H. glycines to develop into mature cysts with their FI value below 5 as well. Our results demonstrated that legume plants in both M. truncatula and M. sativa were not likely to be a model plant for H. glycines because of an extreme high resistance. Reference | Related Articles | Metrics Select Morphological and molecular characterizations of cereal cyst nematode Heterodera avenae Wollenweber, 1924 from the Czech Republic Shesh Kumari 2017, 16 (03): 532-539.   DOI: 10.1016/S2095-3119(16)61485-5 Abstract （830）      PDF in ScienceDirect       The cereal cyst nematode, Heterodera avenae Wollenweber, 1924, is a major pest of cereal crops throughout the world and causes serious yield losses, especially of wheat.  Previous studies have shown that this species is widely distributed in the Czech Republic.  In this study, seven populations of H. avenae were molecularly studied, and one population was morphologically described.  Three regions (18S, 28S, and internal transcribed spacer 1) of ribosomal DNA were sequenced and the analysis of the 18S gene of six populations did not reveal any variation, whereas the internal transcribed spacer 1 and 28S sequences of six populations differed by only two nucleotides from a population in ?ilina.  Precise and quick identification of cereal cyst nematodes is important for effective control measures and ribosomal sequence analyses of seven populations in this study will be useful in future phylogenetic studies of Heterodera spp. occurring in the Czech Republic. Reference | Related Articles | Metrics Select Field evaluation of Streptomyces rubrogriseus HDZ-9-47 for biocontrol of Meloidogyne incognita on tomato JIN Na, XUE Hui* LI Wen-jing, WANG Xue-yan, LIU Qian, LIU Shu-sen, LIU Pei, ZHAO Jian-long, JIAN Heng 2017, 16 (06): 1347-1357.   DOI: 10.1016/S2095-3119(16)61553-8 Abstract （814）      PDF in ScienceDirect       Streptomyces rubrogriseus HDZ-9-47, isolated from eggs of Meloidogyne spp., was evaluated as a potential biocontrol agent of Meloidogyne incognita under in vitro and protective field.  Microscopic observations showed that HDZ-9-47 parasitized eggs of M. incognita within 7 days.  In vitro, the culture filtrate of HDZ-9-47 caused 97.0% mortality of second-stage juveniles (J2s) of M. incognita and inhibited more than 50% egg hatching.  In the field, compared with the control, the root-knot index and J2s density in the treatment of drench the broth contained 1012 HDZ-9-47 spores were respectively reduced by 51.1 and 80.7% at 90 days post transplantation, which were better than that in other application doses and methods.  In addition, reduction rates of root-knot index and J2s density of the treatment of combined application of HDZ-9-47 with biofumigation was 87.1 and 91.0%, respectively, better than either of HDZ-9-47 or biofumigation used alone or fosthiazate treatment.  And tomato yield also increased by 16.1%.  Together, our results suggest that HDZ-9-47 could be an effective biocontrol agent of M. incognita, and that application of HDZ-9-47 combined with cabbage residue biofumigation was a promising and sustainable option for M. incognita control. Reference | Related Articles | Metrics Select Golden Promise barley (Hordeum vulgare) is a suitable candidate model host for investigation interaction with Heterodera avenae LUO Shu-jie, KONG Ling-an, PENG Huan, HUANG Wen-kun, CUI Jiang-kuan, LIU Jing, QIAO Fen, JIAN Heng, PENG De-liang 2017, 16 (07): 1537-1546.   DOI: 10.1016/S2095-3119(16)61595-2 Abstract （1147）      PDF in ScienceDirect           Heterodera avenae (cereal cyst nematode, CCN) infects many cereal crops and causes serious yield losses worldwide. Interaction studies investigating H. avenae and its hosts are still in their infancy. In this study, a barley model plant, the Hordeum vulgare cultivar Golden Promise, was investigated for its potential as a candidate model host to study its interaction with H. avenae. CCN-infective juveniles were attracted by the root tips and gathered around the root elongation zones of Golden Promise on 0.7% water agar plates. The juveniles invaded the roots and developed successfully until maturation at 40 days after inoculation in sterile sand soil. The cryotomy and syncytium measurements indicated that the syncytia enlarged gradually throughout the development of the nematodes and caused the corresponding root regions to swell obviously. Quantitative real-time PCR analysis showed that the down-regulation of defence-related barley genes and up-regulation of development-related barley genes contribute to the understanding of compatible interaction between H. avenae and Golden Promise. Barley stripe mosaic virus (BSMV) virus-induced gene silencing (VIGS) can be used in the roots of Golden Promise. In conclusion, the Hordeum vulgare cultivar Golden Promise is a suitable candidate model host for interaction studies with Heterodera avenae. The studies presented above document the first CCN host that not only has published genome context but also be compatible to BSMV VIGS.   Reference | Related Articles | Metrics Select Occurrence, identification and phylogenetic analyses of cereal cyst nematodes (Heterodera spp.) in Turkey CUI Jiang-kuan, PENG Huan, LIU Shi-ming, Gul Erginbas Orakci, HUANG Wen-kun, Mustafa Imren, Abdelfattah Amer Dababat, PENG De-liang 2017, 16 (08): 1767-1776.   DOI: 10.1016/S2095-3119(16)61557-5 Abstract （743）      PDF in ScienceDirect       Plant-parasitic nematodes are very common on cereal crops and cause economic losses via reduction in grain quality and quantity. During 2014, 83 soil samples were collected from wheat and barley fields in 21 districts of 13 provinces across five regions (Central Anatolia, Marmara, Aegean, Southeast Anatolia, and Black Sea Region) of Turkey. Cyst-forming nematodes were found in 66 samples (80%), and the internal transcribed spacer (ITS) sequencing and species-specific PCR identified the species in 64 samples as Heterodera filipjevi, Heterodera latipons, and Heterodera avenae. The predominant pathogenic cereal cyst nematode was H. filipjevi, which was found in all five regions surveyed. H. avenae was only detected in Southeast Anatolia whereas H. latipons was detected in Southeast Anatolia and Central Anatolia. ITS-rDNA phylogenetic analyses showed that H. avenae isolates from China clustered with H. australis, and Turkish isolates were closely related to European and USA isolates of this species. H. filipjevi from Turkey and China were clustered closely with those from the UK, Germany, Russia, and the USA. The density of many of these populations exceeded or approached the maximum threshold level for economic loss. To our knowledge, this is the first report of H. filipjevi in Diyarbakir, Edirne, and Kutahya provinces, and the first report of H. avenae in Diyarbakir Province. These results exhibit the most rigorous analysis to date on the occurrence and distribution of Heterodera spp. in Turkey’s major wheat-producing areas, thus providing a basis for more specific resistance breeding, as well as other management practices. Reference | Related Articles | Metrics Select Comparison of rhizosphere and endophytic microbial communities of Chinese leek through high-throughput 16S rRNA gene Illumina sequencing HUANG Yong-hong 2018, 17 (2): 359-367.   DOI: 10.1016/S2095-3119(17)61731-3 Abstract （791）      PDF in ScienceDirect       Chinese leek (Allium tuberosum Rottler ex Sprengel) is a common vegetable in China.  In our previous study, Chinese leek in rotation was found to have significant antifungal and nematicidal activity.  This study’s aim was to investigate the potential antifungal and nematicidal activity associated with rhizosphere or endophytic microbes of Chinese leek.  Thus, a total of 79 261 high-quality sequences were obtained from Chinese leek rhizosphere soil, leaf and root samples.  In the rhizosphere soil, the bacterial community comprised five dominant phyla: Proteobacteria (37.85%), Acidobacteria (10.99%), Bacteroidetes (8.24%), Cyanobacteria (7.79%) and Planctomycetes (7.1%).  The leaf and root bacterial communities comprised two dominant phyla: Cyanobacteria (83.42% in leaf and 75.44% in root) and Proteobacteria (14.75% in leaf and 21.04% in root).  Microbial diversity, richness and evenness in the rhizosphere soil bacterial community were higher than that in the endophytic bacterial communities.  The rhizosphere bacterial community was significantly different from the endophytic bacterial communities.  The endophytic bacterial communities from the leaf and the root were slightly, but not significantly different from each other.  This study’s findings would contribute to the isolation and identification of nematicidal and antifungal bacterial communities in Chinese leek. Reference | Related Articles | Metrics Select Host status of Brachypodium distachyon to the cereal cyst nematode CHEN Chang-long, LIU Shu-sen, LIU Qian, NIU Jun-hai, LIU Pei, ZHAO Jian-long, LIU Zhi-yong, LI Hong-jie, JIAN Heng 2018, 17 (2): 381-388.   DOI: 10.1016/S2095-3119(17)61745-3 Abstract （726）      PDF in ScienceDirect       Cereal cyst nematode (Heterodera avenae, CCN) distributes worldwide and has caused severe damage to cereal crops, and a model host will greatly aid in the study of this nematode.  In this research, we assessed the sensitivity of 25 inbred lines of Brachypodium distachyon to H. avenae from Beijing, China.  All lines of B. distachyon were infested by second-stage juveniles (J2s) of H. avenae from Daxing District of Beijing population, but only 13 inbred lines reproduced 0.2–3 cysts/plant, showing resistance.  The entire root system of the infested B. distachyon appeared smaller and the fibrous roots were shorter and less numerous.  We found that a dose of 1 000 J2s of H. avenae was sufficient for nematode infestation.  We showed that Koz-1 of B. distachyon could reproduce more cysts than TR2A line.  Line Koz-1 also supported the complete life cycles of 5 CCN geographical populations belonging to the Ha1 or Ha3 pathotype group.  Our results suggest that B. distachyon is a host for CCN. Reference | Related Articles | Metrics Select Evaluation of Chinese rice varieties resistant to the root-knot nematode Meloidogyne graminicola Zhan Li-ping, Ding Zhong, Peng De-liang, Peng Huan, Kong Ling-an, Liu Shi-ming, Liu Ying, Li Zhong-cai, HUANG Wen-kun 2018, 17 (03): 621-630.   DOI: 10.1016/S2095-3119(17)61802-1 Abstract （805）      PDF in ScienceDirect       The root-knot nematode Meloidogyne graminicola, which is distributed worldwide, is considered a major constraint on rice production in Asia.  The present study used the root gall index and number of nematodes inside the roots to evaluate resistance/susceptibility to M. graminicola in different subpopulations of Oryza sativa (aus, hybrid aus, indica, hybrid indica, temperate japonica, tropical japonica).  Nematode development in highly resistant varieties was also evaluated.  Analyses of randomly selected 35 varieties showed the number of M. graminicola nematodes inside the roots correlated very strongly (r=0.87, P≤0.05) with the nematode gall index, and the results from pot and field experiments revealed similar rankings of the varieties for resistance/susceptibility.  Among the 136 tested varieties, temperate japonica displayed the highest gall index, followed by tropical japonica, indica, hybrid indica, aus, and hybrid aus. Zhonghua 11 (aus), Shenliangyou 1 (hybrid aus) and Cliangyou 4418 (hybrid indica) were highly resistant to M. graminicola under both pot and field conditions.  Further examination of nematode development suggested that compared to susceptible rice, M. graminicola penetrated less often into highly resistant varieties and more frequently failed to develop into females.  The promising varieties found in the present research might be useful for the breeding of hybrid rice in China and for the further development of practical nematode management measures.    Reference | Related Articles | Metrics Select First report of cereal cyst nematode (Heterodera filipjevi) on winter wheat in Shandong Province, China ZHEN Hao-yang, PENG Huan,ZHAO Hong-hai, QI Yong-hong, HUANG Wen-kun, KONG Ling-an, LIANG Chen, WEN Yan-hua, PENG De-liang 2018, 17 (08): 1912-1913.   DOI: 10.1016/S2095-3119(18)61965-3 Abstract （845）      PDF in ScienceDirect       The cereal cyst nematodes (Heterodera avenae, Heterodera filipjevi, Heterodera latipons) are considered to be one of the most important plant parasitic nematodes attacking most cereals and can cause significant crop losses (Sikora 1988).  In China, H. filipjevi (Madzhidov 1981) Stelter, 1984, was first reported from Henan province (Peng et al. 2010) and a few years later in Anhui province and Xinjiang Uygur Autonomous Region (Peng et al. 2016, 2018) .  In December 2017, a survey for cereal cyst nematodes on winter wheat was conducted in Shandong Province, China.  A total of 79 samples that including roots and rhizosphere soil were collected.  Cysts and second-stage juveniles (J2s) were isolated from each soil sample using the sieving-decanting method.  Wheat roots were stained with acid fusion to observe the development of cereal cyst nematodes.  One sample collected from Yangzhuan Village in Huanggang Town, Shan County of Heze City (GPS 34°38´23.10´´N, 116°05´42.95´´E), Shandong Province, was found that the wheat roots were heavily parasitized by cyst nematodes, and most of the nematodes in roots had developed to fourth-stage (J4) in mid-December of 2017.  The morphological and molecular studies of cyst and J2s were carried out to confirm the identification of H. filipjevi in one winter wheat field soil and root sample from Shan County.  The cysts were lemon shaped with prominent vulval cone, brown to black in colour.  Cuticle with irregular zig-zag pattern.  Neck prominent, vulval cone bifenestrate with horseshoe-shaped fenestra, bullae and underbridge strongly developed.  The main morphometrics of cysts (n=8) were length (including neck) (688 to 948 μm, mean=794 μm, standard deviation=87 μm), width (465 to 620 μm, mean=529 μm, standard deviation=63 μm), neck length (71.5 to 126.3 μm, mean=86.5 μm, standard deviation=9.2 μm), fenestra length (43.8 to 71.3 μm, mean=58.0 μm, standard deviation=15.1 μm), fenestra width (19.8 to 32.0 μm, mean=25.0 μm, standard deviation=3.9 μm), length of vulval slit (8.1 to 9.7 μm, mean=9.1 μm, standard deviation=0.5 μm) and length of underbridge (64.5 to 101.3 μm, mean=82.6 μm, standard deviation=12.8 μm).  Measurements of J2s (n=10); body length (556.7 to 617.0 μm, mean=584.3 μm, standard deviation=23.2 μm); stylet (22.8 to 24.1 μm, mean=23.3 μm, standard deviation=0.4 μm), tail (59.6 to 68.6 μm, mean=65.8 μm, standard deviation=3.5 μm) and hyaline tail terminus (35.9 to 41.1 μm, mean=38.6 μm, standard deviation=2.1 μm).  Genomic DNA was isolated from single cysts (n=6), and the internal transcribed spacer regions were amplified with primers TW81 (5´-GTTTCCGTAGGTGAACCTGC-3´) and AB28 (5´-ATATGCTTAAGTTCAGCGGGT-3´) (Joyce et al. 1994) and 28S rDNA-D2/D3 regions were amplified with primers D2A (5´-ACAAGTACCGTGAGGGAAAGTTG-3´) and D3B (5´-TCGGAAGGAACCAGCTACTA-3´) (Subbotin et al. 2006).  The obtained internal transcribed spacer regions (ITSs) sequences (GenBank accession MG859977) is 99% identical to those of H. filipjevi from Turkey (KR704292.1 and KR704304.1), the United States (KP878490.1 and GU079654.1) and China (KY448473.1 and KY448473.1).  The obtained 28S rDNA-D2/D3 sequences (GenBank accession MG859980) also to be 99 to 100% identical to those of H. filipjevi from China (GU083597.1, KT314235.1, GU083592.1).  The species-specific primers of H. filipjevi (HfF1, 5´-CAGGACGAAACTCATTCAACCAA-3´; HfR1, 5´-AGGGCGAACAGGAGAAGATTAGA-3´) were also used to identify this population (Peng et al. 2013), the specific band was obtained species-specific primers of H. filipjevi.  Based on the morphological and molecular data, the species of the cyst-forming nematode was identified as H. filipjevi.  As far as we know, this is the first report of H. filipjevi in Shandong Province, China.  The population density of H. filipjevi were found much higher than those of other CCN, it can serious infect winter wheat at seedling stage which often cause economically damaging to wheat, so the spread of H. filipjevi would be a risk for the cereal production of Shandong province.  Reference | Related Articles | Metrics Select Morphological and molecular characterization of the rice root-knot nematode, Meloidogyne graminicola, Golden and Birchfeild, 1965 occurring in Zhejiang, China TIAN Zhong-ling, Munawar Maria, Eda Marie Barsalote, Pablo Castillo, ZHENG Jing-wu 2018, 17 (12): 2724-2733.   DOI: 10.1016/S2095-3119(18)61971-9 Abstract （365）      PDF in ScienceDirect       The rice root-knot nematode Meloidogyne graminicola is a severe pest of rice.  In China, it was first reported from Hainan Province, and later from several other provinces.  In the present study, a rice root-knot nematode population found from the rice cultivation areas of Zhejiang Province, China is characterized via molecular analysis using internal transcribed spacer (ITS) and cytochrome c oxidase subunit II (coxII)-16S rRNA genes and scanning electron microscopy (SEM) observations of males and the second-stage juveniles.  Morphometric data and molecular sequence comparisons for all M. graminicola populations occurring in China are also provided.  The overall morphology of M. graminicola found in Zhejiang match well with the original description, though males have a slightly longer body and stylet, and a shorter tail, while the second-stage juvenile is also slightly longer than in the original description.  This is the first report of M. graminicola from Zhejiang.  Phylogenetic studies based on coxII suggest that all the Chinese populations belong to Type B.  This study expands knowledge of the increasing distribution and phylogenetic relationships of M. graminicola that occur in China.  Reference | Related Articles | Metrics Select Chemical mutagenesis and soybean mutants potential for identification of novel genes conferring resistance to soybean cyst nematode GE Feng-yong, ZHENG Na, ZHANG Liu-ping, HUANG Wen-kun, PENG De-liang, LIU Shi-ming 2018, 17 (12): 2734-2744.   DOI: 10.1016/S2095-3119(18)62105-7 Abstract （283）      PDF （5218KB）（538）       The resistance of soybean (Glycine max (L.) Merr.) to soybean cyst nematode (SCN, Heterodera glycines Ichinohe), which is a devastating pathogen in soybean production and causes a large quantity of annual yield loss worldwide, can shift during the long-term interaction and domestication.  It is vital to identify more new resistance genetic sources for identification of novel genes underlying resistance to SCN for management of this pathogen.  In the present study, first, two ethane methylsulfonate-mutagenesis soybean M2 populations of PI 437654, which shows a broad resistance to almost all of SCN races, and Zhonghuang 13, which is a soybean cultivar in China conferring strong resistance to lodging, were developed.  Many types of morphological phenotypes such as four- and five-leaflet leaves were observed from these two soybean M2 populations.  Second, 13 mutants were identified and confirmed to exhibit alteration of resistance to SCN race 4 through the forward genetic screening of 400 mutants of the PI 437654 M2 population, the rate of mutants with alteration of SCN-infection phenotype is 3.25%.  Third, these identified mutants were further verified not to show any changes in the genomic sequences of the three known SCN-resistant genes, GmSHMT08, GmSNAP18 and GmSANP11, compared to the wild-type soybean; and all of them were still resistant to SCN race 3 similar to the wild-type soybean.  Taken together, we can conclude that the 13 mutants identified in the present study carry the mutations of the new gene(s) which contribute(s) to the resistance to SCN race 4 in PI 437654 and can be potentially used as the genetic soybean sources to further identify the novel SCN-resistant gene(s).    Reference | Related Articles | Metrics Select Pectate lyase is a factor in the adaptability for Heterodera glycines infecting tobacco TIAN Zhong-ling, SHI Hong-li, Munawar Maria, ZHENG Jing-wu 2019, 18 (3): 618-626.   DOI: 10.1016/S2095-3119(18)62090-8 Abstract （218）      PDF （1094KB）（660）       The soybean cyst nematode, Heterodeara glycines, is a serious pathogen of soybean, and reported to be the host of a wide range of Fabaceae.  In the present study, the host specificity and reproductivity of two populations of H. glycines collected from soybean and tobacco were identified and characterized.  The comparative identity between β-1,4-endoglucanase, pectate lyase and chorismate mutase of H. glycines parasitizing on soybean and tobacco were 99, 97 and 98%, respectively.  The qRT-PCR analysis indicated that the expression of pectate lyase 2 gene was significantly higher in second-stage juveniles of H. glycines Henan population parasitizing on tobacco than that of H. glycines Shanxi population parasitizing on soybean.  In addition, the pectic acid content of cell wall was significantly higher (45%) in the roots of tobacco than the roots of soybean.  Our results indicate that the changes in transcript parasitism genes may be a result of long-term evolution illustrating how a plant-parasitic nematode adapts to the host environment for optimal infestation and survival.   Reference | Related Articles | Metrics Select The synergistic advantage of combining chloropicrin or dazomet with fosthiazate nematicide to control root-knot nematode in cucumber production HUANG Bin, WANG Qian, GUO Mei-xia, FANG Wen-sheng, WANG Xiao-ning, WANG Qiu-xia, YAN Dong-dong, OUYANG Can-bin, LI Yuan, CAO Ao-cheng 2019, 18 (9): 2093-2106.   DOI: 10.1016/S2095-3119(19)62565-7 Abstract （154）      PDF in ScienceDirect       The highly-damaging root-knot nematode (Meloidogyne spp., RKN) cannot be reliably controlled using only a nematicide such as fosthiazate because of increasing pest resistance.  In laboratory and greenhouse trials, we showed that chloropicrin (CP) or dazomet (DZ) synergized the efficacy of fosthiazate against RKN.  The combination significantly extended the degradation half-life of fosthiazate by an average of about 1.25 times.  CP or DZ with fosthiazate reduced the time for fosthiazate to penetrate the RKN cuticle compared to fosthiazate alone.  CP or DZ combined with low or medium rate of fosthiazate increased the total cucumber yield, compared to the use of each product alone.  A low-dose fosthiazate with DZ improved total yield more than a low dose fosthiazate with CP.  Extending the half-life of fosthiazate and reducing the time for fosthiazate or fumigant to penetrate the RKN cuticle were the two features that gave the fumigant-fosthiazate combination its synergistic advantage over these products used singularly.  This synergy provides the opportunity for farmers to use a low dose of fosthiazate which lowers the risk of RKN resistance.  Farmers could combine DZ at 30 g m–2 with fosthiazate at a low rate of 0.375 g m–2 to control RKN and adequately control two major soil-borne diseases in cucumber greenhouses. Reference | Related Articles | Metrics Select Molecular characterization and functional analysis of two new lysozyme genes from soybean cyst nematode (Heterodera glycines) WANG Ning, PENG Huan, LIU Shi-ming, HUANG Wen-kun, Ricardo Holgado, Jihong Liu-Clarke, PENG De-liang 2019, 18 (12): 2806-2813.   DOI: 10.1016/S2095-3119(19)62766-8 Abstract （111）      PDF in ScienceDirect       Soybean cyst nematode (SCN, Heterodera glycines (I.)) is one of the most important soil-borne pathogens for soybeans.  In plant parasitic nematodes, including SCN, lysozyme plays important roles in the innate defense system.  In this study, two new lysozyme genes (Hg-lys1 and Hg-lys2) from SCN were cloned and characterized.  The in situ hybridization analyses indicated that the transcripts of both Hg-lys1 and Hg-lys2 accumulated in the intestine of SCN.  The qRT-PCR analyses showed that both Hg-lys1 and Hg-lys2 were upregulated after SCN second stage juveniles (J2s) were exposed to the Gram-positive bacteria Bacillus thuringiensis, Bacillus subtilis or Staphylococcus aureus.  Knockdown of the identified lysozyme genes by in vitro RNA interference caused a significant decrease in the survival rate of SCN.  All of the obtained results indicate that lysozyme is very important in the defense system and survival of SCN.  Reference | Related Articles | Metrics Select Evaluation of soil flame disinfestation (SFD) for controlling weeds, nematodes and fungi WANG Xiao-ning, CAO Ao-cheng, YAN Dong-dong, WANG Qian, HUANG Bin, ZHU Jia-hong, WANG Qiu-xia, LI Yuan, OUYANG Can-bin, GUO Mei-xia, WANG Qian 2020, 19 (1): 164-172.   DOI: 10.1016/S2095-3119(19)62809-1 Abstract （140）      PDF in ScienceDirect       Soil flame disinfestation (SFD) is a form of physical disinfestation that can be used both in greenhouses and on field crops.  Its use for soil disinfestation in different crop growing conditions makes it increasingly attractive for controlling soil-borne pathogens and weeds.  But little is known about the effect on weeds and soilbrone diseases.  This study reports on greenhouses and field crops in China that determined the efficacy of SFD to control weeds, nematodes and fungi.  It also determined the impact of SFD on the soil physical and chemical properties (water content, bulk density, NO3–-N content, NH4+-N content, conductivity and organic matter) in three field trials.  A second generation SFD machine was used in these trials.  SFD treatment significantly reduced weeds (>87.8%) and root-knot nematodes (Meloidogyne incognita) (>98.1%).  Plant height and crop yield was significantly increased with SFD treatment.  NO3–-N and NH4+-N increased after the SFD treatment, and there was also an increase in soil conductivity.  Water content, bulk density and organic matter decreased significantly in the soil after the SFD treatment compared to the control.  Soil flame disinfestation is a potential technique for controlling weeds and diseases in greenhouses or in fields.  SFD is a non-chemical, safe, environmentally-friendly soil disinfection method.  Reference | Related Articles | Metrics Select Biofumigation: An alternative strategy for the control of plant parasitic nematodes Rebecca Jean Barnes BRENNAM, Samantha GLAZE-CORCORAN, Robert WICK, Masoud HASHEMI 2020, 19 (7): 1680-1690.   DOI: 10.1016/S2095-3119(19)62817-0 Abstract （157）      PDF in ScienceDirect       Plant-parasitic nematodes wreak havoc on the yield and quality of crops worldwide.  Damage from these pests is estimated to exceed US$100 billion annually but is likely higher due to misdiagnosis.  Nematode damage may be catastrophic, but historically the solution has been damaging as well.  Use of the synthetic nematicide methyl bromide (MBr) poses risks to the environment and to human health.  Biofumigation, the use of plant material and naturally produced compounds to control pests, is an increasingly feasible method of pest management.  The process acts through the growth or incorporation of plant material into the soil, that, over the course of its degradation, releases glucosinolates that break down into nematotoxic isothiocyanates.  These secondary plant metabolites exist naturally in commonly grown plants, most of which belong to the Brassicaceae family.  Research endeavors have increasingly explored the potential of biofumigation.  The reaction of target pests, the selection of biofumigant, and ideal environments for efficacy continue to be evaluated.  This review seeks to provide a cost and benefit assessment of the status of biofumigation for the control of plant-parasitic nematodes as an alternative to conventional methyl bromide usage.    Reference | Related Articles | Metrics Select Identification and resistant characterization of legumes sources against Meloidogyne incognita #br# Pornthip RUANPANUN, Prakit SOMTA 2021, 20 (1): 168-177.   DOI: 10.1016/S2095-3119(20)63414-1 Abstract （117）      PDF in ScienceDirect       Root-knot nematodes (RKNs; Meloidogyne spp.) are becoming a serious problem in legume production.  This study identified Vigna genotypes exhibiting resistance to M. incognita (RKN) and characterized the modes of the resistance to M. incognita.  In total, 279 accessions from 21 Vigna species were screened for resistance based on a galling index (GI) and an egg mass index (EI).  Seven accessions were highly resistant to RKN with GI≤25, namely JP74716 (V. mungo var. mungo; cultivated black gram), JP107881 (V. nepalensis), JP229392 (V. radiata var. sublobata; wild mungbean), AusTRCF118141 (V. unguiculata subsp. unguiculata; cultivated cowpea), AusTRCF306385 (V. unguiculata subsp. unguiculata), AusTRCF322090 (V. vexillata var. vexillata; wild zombi pea) and JP235929 (V. vexillata var. vexillata).  JP229392 and AusTRCF322090 were the most resistant accessions having EI values of 18.74 and 1.88, respectively.  Continuous culture of M. incognita on both JP229392 and AusTRCF322090 resulted in a weakness in pathogenic ability for this RKN.  The resistance in JP229392 and AusTRCF322090 to RKN appeared to be antibiosis that was associated with reduced nematode penetration, retardation of nematode development and impeding giant cell formation.  The Vigna germplasm resistance to RKN identified in this study could be utilized as gene sources for the development of RKN-resistant Vigna cultivars.   Reference | Related Articles | Metrics Select Natural nematicidal active compounds: Recent research progress and outlook CHEN Ji-xiang, SONG Bao-an 2021, 20 (8): 2015-2031.   DOI: 10.1016/S2095-3119(21)63617-1 Abstract （224）      PDF in ScienceDirect       Plant-parasitic nematodes cause substantial economic losses to global agriculture yearly.  The use of nematicides is an effective way of controlling plant-parasitic nematodes.  However, the long-term use of traditional organophosphorus and carbamate chemical nematicides can lead to increased nematode resistance.  With the increasing awareness of the necessity for the protection of the environment and human health, highly toxic nematicides no longer meet the developmental requirements of modern agriculture.  Recently, many studies have been undertaken on the isolation and nematicidal activity of natural products against plant-parasitic nematodes and Caenorhabditis elegans.  As an important model nematode, C. elegans plays a vital reference role in studying plant-parasitic nematodes regarding nematicidal activity, metabolic mechanism, and modes of action and target.  We reviewed the latest research progress of natural nematicidal active compounds against plant-parasitic nematodes and C. elegans over the past ten years, discussed the structure-activity relationship and mechanism of action, and examined the development and application of natural nematicidal active compounds. Reference | Related Articles | Metrics Select Identification of Heterodera schachtii on sugar beet in Xinjiang Uygur Autonomous Region of China PENG Huan, LIU Hui, GAO Li, JIANG Ru, LI Guang-kuo, GAO Hai-feng, Wu Wei, WANG Jun, Zhang Yu, HUANG Wen-kun, KONG Ling-an, PENG De-liang 2022, 21 (6): 1694-1702.   DOI: 10.1016/S2095-3119(21)63797-8 Abstract （257）      PDF in ScienceDirect       The sugar beet cyst nematode, Heterodera schachtii, is a major parasite of sugar beet which has been recognized and listed as a quarantine nematode in China and more than 20 countries and regions worldwide.  A survey for important nematodes was undertaken in the sugar beet planting area of China during 2015–2018, and numerous cysts were collected from sugar beet fields in Xinyuan County, Xinjiang Uygur Autonomous Region of China.  The observations of morphological and morphometric characteristics revealed that cysts, vulval cones and second-stage juveniles of the Xinjiang population were in the same range of each other and within those of other reported H. schachtii populations.  Molecular analysis of rDNA-ITS, 28S-D2/D3 and mtDNA cytochrome c oxidase subunit 1 (COI) gene sequences suggested that the Xinjiang population clustered in a branch with those foreign populations, and the sequence similarity was as high as 99.81–100%.  Moreover, this result was confirmed by PCR assay with species-specific primer SHF6 and rDNA2 of H. schachtii, and the pathogenicity test confirmed successful Xinjiang population reproduction in both plant hosts.  In conclusion, based on morphological and molecular characterization, this study confirmed that the cyst nematode population collected from sugar beet fields in Xinjiang is H. schachtii.  As far as we know, this is the first report of H. schachtii on sugar beets in Xinjiang, China. Reference | Related Articles | Metrics Select Isolation and molecular characterization of entomopathogenic nematode, Heterorhabditis sp. from an arable land in Nigeria Fisayo Y. DARAMOLA, Osarenkhoe O. OSEMWEGIE, Stephen O. OWA, Samuel B. ORISAJO, Evbuomwan IKPONMWOSA, Elizabeth T. ALORI 2021, 20 (10): 2706-2715.   DOI: 10.1016/S2095-3119(21)63609-2 Abstract （130）      PDF in ScienceDirect       The occurrence of entomopathogenic nematodes (EPNs) in arable soil samples from Nigeria was investigated using Baermann extraction tray and insect-bait (White’s trap) techniques.  Isolates were tested for infectivity using the larvae of Galleria mellonella (greater moth) and Tenebrio molitor (mealworm).  The study revealed a new species of Heterorhabditis (MT371593) in soil samples that were randomly collected from an arable farmland cultivated with cassava TMS-30572 at the Teaching and Research Farm of Landmark University, Nigeria.   Amplification of the internal transcribed spacer region (ITS) of the ribosomal DNA produced a nucleotide sequence of 933 base pairs (bp).  A BLASTN search of GenBank showed that the sequence of the Nigerian isolate is identical at 99% similarity to that of Heterorhabditis sp. from Thailand.   Infectivity test of the isolate showed 100% mortality against T. molitor larvae within 48 h of exposure while only 80% mortality was recorded for G. mellonella after 1 week of exposure.  This is the first account of Heterorhabditis sp. in Nigeria.  The varying degrees of infectivity against mealworm and greater moth observed in this study proved that the Nigerian isolate of Heterorhabditis sp. could potentially be an attractive option in the management of insect pests of cash crops. Reference | Related Articles | Metrics Select Effect of Aspergillus niger NBC001 on the soybean rhizosphere microbial community in a soybean cyst nematode-infested field JIN Na, LIU Shi-ming, PENG Huan, HUANG Wen-kun, KONG Ling-an, PENG De-liang 2021, 20 (12): 3230-3239.   DOI: 10.1016/S2095-3119(20)63467-0 Abstract （155）      PDF in ScienceDirect       Soybean cyst nematode (SCN, Heterodera glycines Ichinohe) is one of the most important pests causing considerable damage to soybean (Glycine max (L.) Merr.) around the world.  Biocontrol provides a strategy for sustainable nematode control.  Previously, Aspergillus niger NBC001 was isolated from the cysts of Heterodera spp. and able to control H. glycines and promote the growth of soybean in a pot experiment.  In this study, the effects of NBC001 on H. glycines density and on the soybean rhizosphere microbial community in a soybean cyst nematode-infested field were studied.  The results showed that NBC001 could suppress H. glycines by 31.7% in the field.  High-throughput sequencing analysis showed that NBC001 had no significant influence on soybean rhizosphere microbial community structure, indicating that seed coat-dressing with the concentrated culture filtrate of NBC001 was safe for the soil ecological environment.  In addition, high-throughput sequencing results demonstrated that at 10 days post transplantation, NBC001 increased the abundances of Actinobacteria and Acidobacteria, but decreased the abundances of Bacteroidetes and Gemmatimonadetes at the phylum level.  Meanwhile, the abundances of Phyllobacterium, Ralstonia and H16 were increased, while the abundances of Adhaeribacter, Gemmatimonas, Sphingomonas, Flavisolibacter were suppressed by application of NBC001.  However, at 90 days post transplantation, NBC001 only increased the abundances of Aeromicrobium and RB41 whereas it decreased the abundance of H16.  The results indicated that application of NBC001 increased the relative abundances of the beneficial microorganisms such as Actinobacteria, Acidobacteria, Aeromicrobium and Phyllobacterium in the soil.  In summary, NBC001 is an eco-friendly biocontrol agent for H. glycines control.  Reference | Related Articles | Metrics Select First record of the golden potato nematode Globodera rostochiensis in Yunnan and Sichuan provinces of China JIANG Ru, PENG Huan, LI Yun-qing, LIU Hui, ZHAO Shou-qi, LONG Hai-bo, HU Xian-qi, GE Jian-jun, LI Xing-yue, LIU Miao-yan, SHAO Bao-lin, PENG De-liang 2022, 21 (3): 898-899.   DOI: 10.1016/S2095-3119(21)63845-5 Abstract （460）      PDF in ScienceDirect       The potato cyst nematodes (PCN) Globodera rostochiensis (Wollenweber) Skarbilovich, 1959 is considered the most damaging nematode pest of potato worldwide that causes significant yield losses, and this nematode is recognized and listed as a quarantine nematode in many countries (EPPO 2017).  China is currently the largest producer of potato in the world, while the total production is also the highest (Guan and Cai 2019).  The survey for cyst nematodes on potato were conducted in Yunnan and Sichuan provinces of China during 2018–2020, numerous cysts were observed on potato roots in Huize County and Ludian County of Yunnan Province, Zhaojue County and Yuexi County of Sichuan Province.  Cysts and second-stage juveniles (J2s) were isolated from each soil sample using the Cobb decanting and sieving method.  The morphology of cysts and J2s and molecular analysis established the identity of this species as golden cyst nematode Globodera rostochiensis (Subbotin et al. 2010).  For morphological analysis, the cysts were characterized by smoothly rounded with a small projecting neck, brown and golden color, terminal cone was absent and circumfenestrate.  The key morphometrics of cysts (n=25) were: length excluding neck 705±24 (689–747) μm, width 698±28 (678–759) μm, number of cuticular ridges between anus and vulval fenestra 17.3±1.7 (14–19); fenestral diameter 13.6±1.1 (12.25–15.45) μm; distance from anus to the edge of fenestra 63.7±11.3 (48.23–79.14) μm; Granek’s ratio 4.7±0.7 (3.92–5.75).  The key morphometrics of J2s (n=25): body length 453.9±16.6 (440–496) μm, stylet length 21.9±1.0 (20.3–24.3) μm, tail length 51.1±3.2 (45.5–55.5) μm, and hyaline region length 24.4±2.5 (21.7–29.9) μm.  Morphology of the cysts and J2 were consistent with those of G. rostochiensis (Subbotin et al. 2010; EPPO 2017).  Moreover, the identification result was confirmed by PCR using universal primers TW81 (5´-GTTTCCGTAGGTGAACCTGC-3´) and AB28 (5´-ATATGCTTAAGTTCAGCGGGT-3´) for ITS region and D2A (5´-TTTTTTGGGCATCCTGAGGTTTAT-3´) D3B (5´-AGCACCTAAACTTAAAACATAATGAAAATG-3´) for rDNA-28S region, respectively.  The ITS rDNA sequences (GenBank accessions MZ042365, MZ042366, MZ042369, and MZ042370) exhibited 99.83% identity match to G. rostochiensis sequences available in the GenBank (GQ294513).  Sequence from the 28S region (GenBank accessions MZ057595, MZ057596, MZ057599, and MZ057600) was 99.33% similar to those of G. rostochiensis isolate from MF773722.  The species was also confirmed with species-specific primers ITS5 (5´-GGAAGTAAAAGTCGTAACAAGG-3´) and PITSr3 (5´-AGCGCAGACATGCCGCAA-3´) (Bulman and Marshall 1997), a single 434-bp fragment was obtained from Huize, Ludian, Zhaojue and Yuexi populations.  The pathog enicity testing of Huize, Ludian, Zhaojue and Yuexi, three weeks-old potato plants (cv. Qinshu 9) were inoculated with 2 000 eggs, and cultured in an incubator at 23°C/20°C with a 16 h/8 h light/dark photoperiod.  After three months inoculation, 36±7.2 cysts and females were extracted from the infested potato roots, no females and cysts were observed on control plants.   This is the first report of potato golden cyst nematode G. rostochiensis in China.   Reference | Related Articles | Metrics Select Study on burrowing nematode, Radopholus similis, pathogenicity test system in tobacco as host YANG Si-hua, ZHAO Li-rong, DING Sha, TANG Shi-qiao, CHEN Chun, ZHANG Huan-xin, XU Chun-ling, XIE Hui 2022, 21 (9): 2652-2664.   DOI: 10.1016/j.jia.2022.07.021 Abstract （152）      PDF in ScienceDirect       Radopholus similis (Cobb 1893) Thorne (1949) is a destructive migratory endoparasitic plant nematode.  In this study, the pathogenic process of R. similis infection in Nicotiana benthamiana (tobacco) was studied using quartz sand culture in laboratory.  The results showed that R. similis mainly parasitised the root cortex, leading to cortical cell decomposition and tissue decay.  We optimised the inoculation conditions to establish a method for determining the pathogenicity of R. similis as follows: (1) a glass culture tube was filled with quartz sand (about 1/3 of the height) and sterilised twice; (2) 20-day-old N. benthamiana seedlings were transplanted into test tubes and cultivated for 10 days at (25±1)°C; (3) R. similis female nematodes were inoculated in the root rhizosphere at a rate of 150 nematodes per plant; (4) the number of nematodes, disease severity, and growth of the plant at 30 days post-inoculation (dpi) were determined.  The pathogenicity of eight R. similis populations from different hosts was determined, which proved the feasibility of this method. Reference | Related Articles | Metrics Select Molecular and morphological characterization of stunt nematodes of wheat, maize, and rice in the savannahs of northern Nigeria Sulaiman ABDULSALAM, , PENG Huan, LIU Shi-ming, HUANG Wen-kun, KONG Ling-an, PENG De-liang 2022, 21 (2): 586-595.   DOI: 10.1016/S2095-3119(21)63696-1 Abstract （220）      PDF in ScienceDirect       Stunt nematodes (Tylenchorhynchus spp.) are obligate migratory root ecto-parasitic nematodes found in the fields of many cultivated crops.  These nematodes, with phyto-sanitary potential, are frequently ignored or misdiagnosed as pests, and this may pose a threat to food security.  The accuracy of its identification based on a morphological approach has been challenged recently, due to the overlapping of the morphological and morphometric characters of the species.  Consequently, the objective of this study is to identify and characterize stunt nematodes present in 54 fields cultivated with cereal crops (wheat, maize and rice) in the savannahs of northern Nigeria, using integrative taxonomy and molecular approaches.  The molecular and morphological studies identified and confirmed the presence of T. annulatus as the occurring specie in the savannahs of northern Nigeria.  The phylogenetic analysis was carried out using the internal transcribed spacer (ITS) and 28S genes of ribosomal DNA further confirmed the presence of T. annulatus.  The first molecular characterization and sequences of the ITS and 28S rDNA gene for T. annulatus from Nigeria were provided by this research.  Also, according to our literature search, this is the first report on T. annulatus in wheat, maize and rice in the savannahs of northern Nigeria.  Further study to test the pathogenicity of the parasitic nematode species found in this survey is recommended for the prioritization and development of efficient management strategies. Reference | Related Articles | Metrics Select Study on PCR rapid molecular detection technique of Meloidogyne vitis YANG Yan-mei, LIU Pei, LI Hong-mei, PENG Huan, DU Xia, DONG Ye, HU Xian-qi 2022, 21 (11): 3408-3416.   DOI: 10.1016/j.jia.2022.08.100 Abstract （235）      PDF in ScienceDirect       Meloidogyne vitis is a new root-knot nematode parasitic on grape root in Yunnan Province, China.  In order to establish a rapid, reliable and specific molecular detection method for M. vitis, the species-specific primers were designed with rDNA-ITS (ribosomal DNA internal transcribed spacer) gene fragment as the target.  The reaction system was optimized and the reliability, specificity and sensitivity of primer were testified, therefore, a rapid PCR detection method for M. vitis was established.  The result showed that the optimal annealing temperature of the primers was 53°C, which was suitable for the detection of different life stages of M. vitis.  Specificity test showed that the specific fragment size of 174 bp was obtained from M. vitis, but other five non-target nematodes did not have any amplification bands, thus effectively distinguish M. vitis and the other five species, and could specifically detect the M. vitis from mixed populations.  Sensitivity test showed that this PCR technique could detect the DNA of a single second-stage juvenile (J2) and 10–4 female.  Futhermore, this PCR technique could be used to detect directly M. vitis from soil samples.  The rapid, sensitive and specific PCR molecular detection technique could be used for the direct identification of a single J2 of M. vitis and the detection of M. vitis in mixed nematode populations and the detection of two J2s or one male in 0.5 g soil samples, which will provide technical support for the investigation of the occurrence and damage of M. vitis and the formulation of efficient green control strategies. Reference | Related Articles | Metrics Select The new effector AbSCP1 of foliar nematode (Aphelenchoides besseyi) is required for parasitism rice HUANG Xin, CHI Yuan-kai, Addisie Abate BIRHAN, ZHAO Wei, QI Ren-de, PENG De-liang 2022, 21 (4): 1084-1093.   DOI: 10.1016/S2095-3119(21)63706-1 Abstract （168）      PDF in ScienceDirect       Plant parasitic nematodes secrete effector proteins to parasitize hosts successfully.  Of these proteins, serine carboxypeptidases have critical roles in pathogenicity.  This study investigated the role of new effector AbSCP1 in Aphelenchoides besseyi pathogenicity.  In situ hybridization and qRT-PCR analyses indicated that AbSCP1 was exclusively expressed in the esophageal glands and upregulated in juveniles.  Subcellular localization assays indicated that the protein was expressed in the nucleus.  The ability to hydrolyze C-terminal amino acid residues was proven for AbSCP1.  Moreover, RNAi significantly reduced the expression of AbSCP1 and RNAi-treated nematodes’ reproductive potential.  Pathogenicity assays on rice showed that RNAi-treated nematodes were less pathogenic than the untreated control groups.  These results suggest the important role of AbSCP1 in the A. besseyi infection process. Reference | Related Articles | Metrics Select A fragment of a 70-kDa Heterodera glycines heat shock protein (HgHSP70) interacts with soybean cyst nematode-resistant protein GmSHMT08 LIU Zhi, ZHANG Liu-ping, ZHAO Jie, JIAN Jin-zhuo, PENG Huan, HUANG Wen-kun, KONG Ling-an, PENG De-liang, LIU Shi-ming 2022, 21 (10): 2973-2983.   DOI: 10.1016/j.jia.2022.07.048 Abstract （228）      PDF in ScienceDirect       Soybean cyst nematode (SCN) Heterodera glycines is considered as the major constraint to soybean production.  GmSHMT08 at Rhg4 locus on chromosome 08, encoding a serine hydroxylmethyltransferase, is a major gene underlying resistance against H. glycines in Peking-type soybeans.  However, the molecular mechanism underpinning this resistance is less well characterized, and whether GmSHMT08 could interact with proteins in H. glycines remains unclear.  In this study, yeast two-hybrid screening was conducted using GmSHMT08 as a bait protein, and a fragment of a 70-kDa heat shock protein (HgHSP70) was screened from H. glycines that exhibited interaction with GmSHMT08.  This interaction was verified by both GST pull-down and bimolecular fluorescence complementation assays.  Our finding reveals HgHSP70 could be applied as a potential candidate gene for further exploring the mechanism on GmSHMT08-mediated resistance against SCN H. glycines. Reference | Related Articles | Metrics Select Resistance of barley varieties to Heterodera avenae in the Qinghai–Tibet Plateau, China Yan Jia-hui, Jia Jian-ping, JIANG Li-ling, Peng De-liang, Liu Shi-ming, Hou Sheng-ying, YU Jing-wen, Li Hui-xia, Huang Wen-kun 2022, 21 (5): 1401-1413.   DOI: 10.1016/S2095-3119(21)63769-3 Abstract （149）      PDF in ScienceDirect       The cereal cyst nematode, Heterodera avenae, is one of the most economically important pathogens impacting the worldwide production of cereals and is widely distributed in more than 16 regions in China.  The present study used the numbers of nematodes inside the plant roots to evaluate the resistance/susceptibility of different subpopulations of barley Hordeum vulgare (QH2R, QH6R and TB2R) to H. avenae under field and pot conditions.  Nematode development in two highly resistant varieties was also evaluated by in vivo experiment and microscopic observation.  Analyses of 186 selected varieties showed the numbers of susceptible varieties identified with the number of females/cysts per plant (NFP) method were significantly higher than those identified with the Pf/Pi ratio (PPR) method, which indicated that the NFP method rather than the PPR method is more reliable to evaluate the resistance of barley.  The field and pot experiment results indicated that the QH2R subpopulation had lower females/cysts numbers than QH6R and TB2R subpopulations, and eight HR varieties (Sunong 7617, Sunong 7635, Dongyuan 87-14, Rudong 14-46, Rudong 87-57, Rudong 87-8-45, Rudong 88-14-2, and Rudong 88-67-1) were identified in QH2R, with the NFP numbers below 4.2.  Further microscopic observation of nematode development suggested that H. avenae often penetrated less into highly resistant varieties (Sunong 7635 and Dongyuan 87-14) and more frequently failed to develop into females than the susceptible barleys.  The promising resistant varieties identified in the present research might be helpful for breeders to develop CCN-resistant cultivars and control H. avenae populations effectively at low costs. Reference | Related Articles | Metrics Select Potassium sulphate induces resistance of rice against the root-knot nematode Meloidogyne graminicola LIU Mao-Yan, PENG De-liang, SU Wen, XIANG Chao, JIAN Jin-zhuo, ZHAO Jie, PENG Huan, LIU Shi-ming, KONG Ling-an, DAI Liang-ying, HUANG Wen-kun, LIU Jing 2022, 21 (11): 3263-3277.   DOI: 10.1016/j.jia.2022.08.002 Abstract （267）      PDF in ScienceDirect       Potassium (K), an important nutrient element, can improve the stress resistance/tolerance of crops.  The application of K in resisting plant-parasitic nematodes shows that the K treatment can reduce the occurrence of nematode diseases and increase crop yield.  However, data on K2SO4 induced rice resistance against the root-knot nematode Meloidogyne graminicola are still lacking.  In this work, K2SO4 treatment reduced galls and nematodes in rice plants and delayed the development of nematodes.  Rather than affecting the attractiveness of roots to nematodes and the morphological phenotype of giant cells at feeding sites, such an effect is achieved by rapidly priming hydrogen peroxide (H2O2) accumulation and increasing callose deposition.  Meanwhile, galls and nematodes in rice roots were more in the potassium channel OsAKT1 and transporter OsHAK5 gene-deficient plants than in wild-type, while the K2SO4-induced resistance showed weaker in the defective plants.  In addition, during the process of nematode infection, the expression of jasmonic acid (JA)/ethylene (ET)/brassinolide (BR) signaling pathway-related genes and pathogenesis-related (PR) genes OsPR1a/OsPR1b was up-regulated in rice after K2SO4 treatment.  In conclusion, K2SO4 induced rice resistance against M. graminicola.  The mechanism of inducing resistance was to prime the basal defense and required the participation of the K+ channel and transporter in rice.  These laid a foundation for further study on the mechanism of rice defense against nematodes and the rational use of potassium fertilizer on improving rice resistance against nematodes in the field. 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