Plant-parasitic nematode associated with wheat in central, eastern, and south-eastern Kazakhstan

Plant Disease ◽  
2021 ◽  
Author(s):  
İmren Mustafa ◽  
Göksel Özer ◽  
Timothy Paulitz ◽  
Alexei Morgounov ◽  
Abdelfattah A. Dababat

Kazakhstan is one of the biggest wheat producers, however, its wheat production is far below the average international wheat production standard due to biotic and abiotic stressors. Plant-parasitic nematodes are devastating for cereal production systems worldwide. A comprehensive survey was conducted in 2019 to identify plant-parasitic nematodes associated with wheat in different locations of central, eastern, and south-eastern Kazakhstan. The results revealed 33 root-lesion and 27 cyst nematode populations from the 77 localities sampled. These two genera occurred in separate or in mixed populations. The root-lesion populations were identified as Pratylenchus neglectus and P. thornei while all cyst nematodes were identified as Heterodera filipjevi. The identification of nematodes was firstly performed based on morphological and morphometric features and confirmed by BLAST and phylogenetic analyses based on the internal transcribed spacer and the D2-D3 expansion located in the 28S gene of ribosomal DNA for CCN and RLN populations, respectively. Pratylenchus neglectus and P. thornei populations from Kazakhstan showed a high similarity with the American, European, and Asian populations. Heterodera filipjevi populations formed a well-supported cluster with the corresponding populations from different countries and showed a slightly intraspecific polymorphism. Kazakhstan populations of H. filipjevi may have multiple introductions in Kazakhstan due to the divergence among them. The results of this study are of great importance for breeding programs and will enable awareness to extension advisors to develop measures to control these nematodes in cereal cropping areas in Kazakhstan.

2021 ◽  
Vol 11 (2) ◽  
Author(s):  
Olaf Kranse ◽  
Helen Beasley ◽  
Sally Adams ◽  
Andre Pires-daSilva ◽  
Christopher Bell ◽  
...  

Abstract Plant-parasitic nematodes are a continuing threat to food security, causing an estimated 100 billion USD in crop losses each year. The most problematic are the obligate sedentary endoparasites (primarily root knot nematodes and cyst nematodes). Progress in understanding their biology is held back by a lack of tools for functional genetics: forward genetics is largely restricted to studies of natural variation in populations and reverse genetics is entirely reliant on RNA interference. There is an expectation that the development of functional genetic tools would accelerate the progress of research on plant-parasitic nematodes, and hence the development of novel control solutions. Here, we develop some of the foundational biology required to deliver a functional genetic tool kit in plant-parasitic nematodes. We characterize the gonads of male Heterodera schachtii and Meloidogyne hapla in the context of spermatogenesis. We test and optimize various methods for the delivery, expression, and/or detection of exogenous nucleic acids in plant-parasitic nematodes. We demonstrate that delivery of macromolecules to cyst and root knot nematode male germlines is difficult, but possible. Similarly, we demonstrate the delivery of oligonucleotides to root knot nematode gametes. Finally, we develop a transient expression system in plant-parasitic nematodes by demonstrating the delivery and expression of exogenous mRNA encoding various reporter genes throughout the body of H. schachtii juveniles using lipofectamine-based transfection. We anticipate these developments to be independently useful, will expedite the development of genetic modification tools for plant-parasitic nematodes, and ultimately catalyze research on a group of nematodes that threaten global food security.


2021 ◽  
Vol 4 (2) ◽  
pp. 327-338
Author(s):  
Honey Raj Mandal ◽  
Shambhu Katel ◽  
Sudeep Subedi ◽  
Jiban Shrestha

Plant Parasitic Nematodes are small worm like transparent, bilateral symmetry, pseudocoelomate, multicellular, free living or parasitic microorganism which are predatory, aquatic, terrestrial, entopathogenic, ectoparasite, endoparasite, semi-endoparasite or sedentary. They cause substantial problems to major crops throughout the world, including vegetables, fruits, and grain crops. The root knot and cyst nematodes are economically important pests in numerous crops. Crop damage from nematodes is not readily apparent in most cases, and it often remains hidden by the many other factors limiting plant growth. In the past, the control of the nematodes has been based on the synthetic nematicides, the number of which has been drastically restricted in the EU because of their environmental side effects and subsequent restriction in European Union (EU) rules and regulations. Many other methods like cultural control, biological control, use of biotechnological tools and methods, use of resistant cultivars are tested and proven successful in controlling different species of nematodes all over the world. Alternatively, combinations of the different methods are proven to be highly effective both economically and environmentally.


1999 ◽  
Vol 73 (1) ◽  
pp. 67-71 ◽  
Author(s):  
P. Mendoza de Gives ◽  
K.G. Davies ◽  
M. Morgan ◽  
J.M. Behnke

Populations of Pasteuria penetrans isolated from root-knot nematodes (Meloidogyne spp.) and cyst nematodes (Heterodera spp.) were tested for their ability to adhere to a limited selection of sheathed and exsheathed animal parasitic nematodes, free living nematodes, including Caenorhabditis elegans wild type and several srf mutants, and plant parasitic nematodes. The attachment of spores of Pasteuria was restricted and no spores were observed adhering to any of the animal parasitic nematodes either with or without their sheath or to any of the free living nematodes including C. elegans and the srf mutants. All spore attachment was restricted to plant parasitic nematodes; however, spores isolated from cyst nematodes showed the ability to adhere to other genera of plant parasitic nematodes which was not the case with spores isolated from root-knot nematodes. The results are discussed in relationship to cuticular heterogeneity.


Nematology ◽  
2015 ◽  
Vol 17 (3) ◽  
pp. 249-263 ◽  
Author(s):  
Laura J. Davies ◽  
Axel A. Elling

Plant-parasitic nematodes are a major pest of all agricultural systems, causing extensive economic losses. Natural resistance (R) genes offer an alternative to chemical control and have been shown effectively to limit nematode damage to crops in the field. Whilst a number of resistant cultivars have conferred resistance against root-knot and cyst nematodes for many decades, an increasing number of reports of resistance-breaking nematode pathotypes are beginning to emerge. The forces affecting the emergence of virulent nematodes are complex, multifactorial and involve both the host and parasite of the plant-nematode interaction. This review provides an overview of the root-knot and cyst nematodeRgenes characterised to date, in addition to examining the evolutionary forces influencing nematode populations and the emergence of virulence. Finally, potential strategies to improveRgene durability in the field are outlined, and areas that would benefit from further research efforts are highlighted.


Author(s):  
Wim Wesemael

Abstract This chapter provides information on the methods for initial screening to determine the resistance or susceptibility of plants, cultivars or breeding lines to plant parasitic nematodes. Specific protocols for screening and further resistance breeding on several plant-nematode combinations are described and practical guidelines for screening of Musa germplasm and several screening procedures for cyst nematodes are presented.


Plant Disease ◽  
2019 ◽  
Vol 103 (7) ◽  
pp. 1621-1630 ◽  
Author(s):  
Oliver Chitambo ◽  
Solveig Haukeland ◽  
Komi K. M. Fiaboe ◽  
Florian M. W. Grundler

Plant-parasitic nematodes, particularly root-knot nematodes (RKN: Meloidogyne spp.) and cyst nematodes (CN: Globodera and Heterodera spp.) cause severe yield reduction in most cultivated crops and are of high economic importance. African nightshade (Solanum spp.) and African spinach (Amaranthus spp.) are important African indigenous vegetables (AIV) and are rich sources of nutrition and income. However, their host status to plant-parasitic nematodes remains largely speculative. Therefore, a survey was conducted which revealed that S. villosum exhibited high root galling, whereas on S. scabrum, A. cruentus, and A. dubius root galling was rare or very low. Additionally, soil collected from the rhizosphere of S. villosum and S. scabrum contained few cysts of potato cyst nematodes (PCN), and no developing PCN females were observed on the roots of growing plants. Therefore, we studied the dynamics of RKN and PCN on A. dubius, A. cruentus, S. scabrum, and S. villosum over 2 years in a field experiment. The effects of AIV crop species on RKN and PCN soil infestation were evaluated using susceptible S. lycopersicum or S. tuberosum. After first, second, and third cultivation of A. dubius, A. cruentus, and S. scabrum, RKN infestation of the soil decreased by more than 85%, whereas S. scabrum and S. villosum decreased PCN densities by more than 80%. When cropping susceptible crops, after three seasons of successive cultivation of these AIV, galling index and number of developing PCN females measured on susceptible crops decreased by more than 75%. Wilting and RKN-PCN coinfection incidences also decreased significantly. Here, we present data that support the development of a novel cropping system including African spinach and African nightshade, which reveals a high potential to manage RKN and PCN in an environmentally friendly, effective, and productive way.


2013 ◽  
Vol 53 (4) ◽  
pp. 404-408 ◽  
Author(s):  
Jebraeil Bahmani ◽  
Farhad Khozeini ◽  
Shapour Barooti ◽  
Saeed Rezaee ◽  
Reza Ghaderi

Abstract A survey of plant-parasitic nematodes associated with walnut was carried out in the Sanandej region, of the province of Kurdistan, in western Iran, during the 2011-2012 time period. After taking samples from fifty-four localities and then doing the routine laboratory work for processing, fixing, and mounting of the nematodes, twenty-one species of plant-parasitic nematodes were finally identified. Among the identified species: Cacopaurus pestis, Mesocriconema xenoplax, Pratylenchus vulnus and Meloidogyne incognita are likely to cause damage. Spiral (Helicotylenchus crassatus, H. digonicus, H. pseudorobustus and H. vulgaris), ring (Mesocriconema antipolitanum and M. xenoplax) and root-lesion nematodes (Pratylenchus neglectus, P. thornei, P. vulnus and P. delattrei) were the most predominant nematodes in the sampled area (frequencies in soil were 87.0, 77.8, and 72.2% and 46.3, 20.4 and 14.8% in root samples, respectively). In the present study, Pratylenchus delattrei, Trophurus lomus, Paratylenchus similis, Geocenamus stegus, Helicotylenchus crassatus, Scutellonema brachyurus and Meloidogyne incognita were reported as new species associated with walnut in Iran.


2021 ◽  
pp. 408-413
Author(s):  
Shahid Siddique ◽  
Sebastian Eves-van den Akker

Abstract Plant parasitic nematodes are among the most destructive plant pathogens, causing an estimated US$78 billion yield losses globally. Although approximately 3000 species of plant parasitic nematodes have been described, most of the damage is caused by a small group of root-infecting sedentary endoparasitic nematodes that include root-knot nematodes (Meloidogyne spp.) and cyst nematodes (Heterodera spp.). Given that previous literature amply reviews the breadth of biotechnological methods for the control of plant parasitic nematodes, this chapter will briefly touch on long-standing biotechnological methods but focus on recent progress in, and long-term promise of, the use of CRISPR technology for introducing targeted modifications into host genomes with the goal of enhancing resistance against plant parasitic nematodes. It is predicted that expanding reverse genetic approaches beyond RNA interference, using low-cost, technically simple and efficient transformation (transient or stable) will be the single most important advance in the field in some years.


Author(s):  
Jaeyeong Han ◽  
Alison L Colgrove ◽  
Norman Dennis Bowman ◽  
Nathan Schroeder ◽  
Nathan Kleczewski

One hundred and forty-seven soil samples were collected from corn fields located within 63 Illinois counties during the 2018 and 2020 corn growing seasons. The soil samples were analyzed for frequency and population density of plant-parasitic nematodes. A total of 10 plant-parasitic nematode taxa were identified. Spiral nematode (Helicotylenchus spp.) was the most frequently observed nematode (frequency: 98.6%), followed by lesion nematode (Pratylenchus spp., 85.7%). Other taxa identified included cyst (Heteroderidae, 66.7%), stunt (Tylenchorhynchus spp., 33.3%), lance (Hoplolaimus spp., 29.9%), dagger (Xiphinema spp., 12.9%), pin (Paratylenchus spp., 12.2%), needle (Longidorus spp., 1.4%), stubby-root (Trichodoridae, 1.4%), and ring nematodes (Criconematidae, 0.7%). Nematodes with the greatest population densities included spiral (89 nematodes per 100 cm3 of soil), pin (36), and cyst nematodes (26). Among the 10 nematode taxa, 4.1%, 7.1%, and 2.3% of spiral, lesion, and lance nematodes positive samples exceeded estimated damage thresholds for corn for Illinois, respectively. Results from this survey will help the agricultural community with understanding pathogenic corn nematode populations in the state and prioritize research in this understudied area.


Nematology ◽  
2009 ◽  
Vol 11 (5) ◽  
pp. 739-747 ◽  
Author(s):  
Bartel Vanholme ◽  
Annelies Haegeman ◽  
Joachim Jacob ◽  
Bernard Cannoot ◽  
Godelieve Gheysen

Abstract Plant-parasitic nematodes secrete a plethora of enzymes to degrade polysaccharides of the recalcitrant plant cell wall. Here we report on the presence of a putative endo-1,4-β-galactosidase (EC 3.2.1.89) in cyst nematodes of the genus Heterodera. This enzyme hydrolyses β-1,4-galactan in the hairy regions of pectin and to our knowledge it is the first report of this class of enzymes in animals. The gene was cloned from H. schachtii and subjected to a detailed molecular characterisation. The deduced protein contains a putative signal peptide for secretion, being in agreement with the presumed extracellular function of the mature protein. It has a molecular mass of 33.78 kDa and folds into an (α/β)8 barrel structure typical for glycosyl hydrolases. The two glutamic acids that function as electron donor and acceptor in the active site are conserved. Whole mount in situ hybridisation revealed that the gene is expressed in the subventral pharyngeal glands and the expression was correlated with the onset of parasitism.


Sign in / Sign up

Export Citation Format

Share Document