Bacillus firmus I-1582 promotes plant growth and impairs infection and development of the cyst nematode Heterodera schachtii over two generations

AbstractPlant-parasitic nematodes wreak havoc on crops by root parasitism worldwide. An approach to combat nematode root parasitism is the application of antagonistic microbes like the rhizobacterium Bacillus firmus I-1582 which is promoted as biological control agent. Although B. firmus is a known nematode antagonist in general, the underlying mechanisms about its interaction with nematodes and plants have not yet been elucidated. Therefore, we explored the influence of B. firmus I-1582 as well as its extracellular and secreted molecules on plant–nematode interaction utilizing the plant–pathogen system Arabidopsis thaliana–Heterodera schachtii. We demonstrated that B. firmus I-1582 is attracted by A. thaliana root exudates, particularly by those of young plants. The bacterium colonized the root and showed a strictly pH-dependent development and plant growth promotion effect. Our results revealed that root colonization by B. firmus I-1582 significantly protected A. thaliana from infestation by the beet cyst nematode whereas dead bacterial cells or the culture supernatant were not effective. The bacterium also negatively affected nematode reproduction as well as pathogenicity and development of next generation nematodes. The obtained results highlight B. firmus I-1582 as a promising biocontrol agent that is well suited as an element of integrated control management strategies in sustainable agriculture.

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The beet cyst nematode (Heterodera schachtii): an ancient threat to sugar beet crops in Central Europe has become an invisible actor.

10.1079/9781789247541.0055 ◽

2021 ◽

pp. 394-399

Author(s):

Matthias Daub

Keyword(s):

Sugar Beet ◽

Integrated Management ◽

Nematode Species ◽

Cyst Nematode ◽

Heterodera Schachtii ◽

Future Research ◽

Parasitic Nematodes ◽

Beet Cyst Nematode ◽

Management Optimization ◽

Damage Symptoms

Abstract The beet cyst nematode (BCN) was one of the first discovered plant parasitic nematodes. Heterodera schachtii was observed in 1859 in Halle in Central Germany by the botanist Herman Schacht and described later by Adolf Schmidt in 1871, who named this cyst nematode species after its original discoverer. Partly due to the lack of knowledge about the effect of sugar beet monocultures on the population build-up of BCN, this nematode had a devastating impact on sugar production in 1876 that led to the shutdown of 24 sugar factories in Germany. This chapter discusses the economic importance, distribution, host range, damage symptoms, biology and life cycle, interactions with other nematodes and pathogens, recommended integrated management, and management optimization of H. schachtii. Future research requirements and future developments are also mentioned.

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The impact of management strategies on the development and status of potato cyst nematode populations in Switzerland: An overview from 1958 to present

Plant Disease ◽

10.1094/pdis-04-21-0800-sr ◽

2021 ◽

Author(s):

Andrea Caroline Ruthes ◽

Paul Dahlin

Keyword(s):

Integrated Management ◽

Abiotic Factors ◽

Management Strategies ◽

Monitoring Program ◽

Cyst Nematode ◽

Globodera Pallida ◽

Parasitic Nematodes ◽

Plant Parasitic Nematodes ◽

The Impact ◽

Plant Parasitic

Globodera rostochiensis and Globodera pallida are some of the most successful and highly specialized plant-parasitic nematodes, and appear among the most regulated quarantine pests globally. In Switzerland, they have been monitored by annual surveys since their first detection in Swiss soil, in 1958. The dataset created was reviewed to give an overview of the development and actual status of PCN in Switzerland. Positive fields represent 0.2% of all the samples analyzed, and currently their distribution is limited to central-west and western Switzerland, suggesting that new introduction of PCN and the spread of the initial introduced PCN populations did not occur. In this way, the integrated management used in Switzerland appears to be effective. However, the increasing availability of potato varieties with resistance to G. rostochiensis and the limited availability of varieties with resistance to G. pallida, together with other biotic and abiotic factors promoted changes in the dominance of either species. Consequently, an extended monitoring program would be of interest to Swiss farmers, to avoid favoring virulent traits that could be present within Swiss Globodera populations.

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Expression of a Fungal Lectin in Arabidopsis Enhances Plant Growth and Resistance Toward Microbial Pathogens and a Plant-Parasitic Nematode

Frontiers in Plant Science ◽

10.3389/fpls.2021.657451 ◽

2021 ◽

Vol 12 ◽

Author(s):

Aboubakr Moradi ◽

Mohamed El-Shetehy ◽

Jordi Gamir ◽

Tina Austerlitz ◽

Paul Dahlin ◽

...

Keyword(s):

Disease Resistance ◽

Plant Growth ◽

Pseudomonas Syringae ◽

Plant Disease Resistance ◽

Plant Protection ◽

Microbial Pathogens ◽

Heterodera Schachtii ◽

Parasitic Nematodes ◽

Phytopathogenic Bacterium ◽

Plant Parasitic

Coprinopsis cinerea lectin 2 (CCL2) is a fucoside-binding lectin from the basidiomycete C. cinerea that is toxic to the bacterivorous nematode Caenorhabditis elegans as well as animal-parasitic and fungivorous nematodes. We expressed CCL2 in Arabidopsis to assess its protective potential toward plant-parasitic nematodes. Our results demonstrate that expression of CCL2 enhances host resistance against the cyst nematode Heterodera schachtii. Surprisingly, CCL2-expressing plants were also more resistant to fungal pathogens including Botrytis cinerea, and the phytopathogenic bacterium Pseudomonas syringae. In addition, CCL2 expression positively affected plant growth indicating that CCL2 has the potential to improve two important agricultural parameters namely biomass production and general disease resistance. The mechanism of the CCL2-mediated enhancement of plant disease resistance depended on fucoside-binding by CCL2 as transgenic plants expressing a mutant version of CCL2 (Y92A), compromised in fucoside-binding, exhibited wild type (WT) disease susceptibility. The protective effect of CCL2 did not seem to be direct as the lectin showed no growth-inhibition toward B. cinerea in in vitro assays. We detected, however, a significantly enhanced transcriptional induction of plant defense genes in CCL2- but not CCL2-Y92A-expressing lines in response to infection with B. cinerea compared to WT plants. This study demonstrates a potential of fungal defense lectins in plant protection beyond their use as toxins.

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Molecular insights into the compatible and incompatible interactions between sugar beet and the beet cyst nematode

BMC Plant Biology ◽

10.1186/s12870-020-02706-8 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Razieh Ghaemi ◽

Ebrahim Pourjam ◽

Naser Safaie ◽

Bruno Verstraeten ◽

Seyed Bagher Mahmoudi ◽

...

Keyword(s):

Sugar Beet ◽

Defense Response ◽

Management Strategies ◽

Phenylpropanoid Pathway ◽

Cyst Nematode ◽

Heterodera Schachtii ◽

Time Points ◽

Beet Cyst Nematode ◽

Genes Encoding ◽

Incompatible Interactions

Abstract Background Sugar beet (Beta vulgaris subsp. vulgaris) is an economically important crop that provides nearly one third of the global sugar production. The beet cyst nematode (BCN), Heterodera schachtii, causes major yield losses in sugar beet and other crops worldwide. The most effective and economic approach to control this nematode is growing tolerant or resistant cultivars. To identify candidate genes involved in susceptibility and resistance, the transcriptome of sugar beet and BCN in compatible and incompatible interactions at two time points was studied using mRNA-seq. Results In the susceptible cultivar, most defense-related genes were induced at 4 dai while suppressed at 10 dai but in the resistant cultivar Nemakill, induction of genes involved in the plant defense response was observed at both time points. In the compatible interaction, alterations in phytohormone-related genes were detected. The effect of exogenous application of Methyl Jasmonate and ET-generator ethephon on susceptible plants was therefore investigated and the results revealed significant reduction in plant susceptibility. Genes putatively involved in the resistance of Nemakill were identified, such as genes involved in phenylpropanoid pathway and genes encoding CYSTM domain-containing proteins, F-box proteins, chitinase, galactono-1,4-lactone dehydrogenase and CASP-like protein. Also, the transcriptome of the BCN was analyzed in infected root samples and several novel potential nematode effector genes were found. Conclusions Our data provides detailed insights into the plant and nematode transcriptional changes occurring during compatible and incompatible interactions between sugar beet and BCN. Many important genes playing potential roles in susceptibility or resistance of sugar beet against BCN, as well as some BCN effectors with a potential role as avr proteins were identified. In addition, our findings indicate the effective role of jasmonate and ethylene in enhancing sugar beet defense response against BCN. This research provides new molecular insights into the plant-nematode interactions that can be used to design novel management strategies against BCN.

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The effect of the synthetic plant-growth substance, 2, 4-dichlorophenoxyacetic acid, on the host–parasite relationships of some plant-parasitic nematodes in monoxenic callus culture

Parasitology ◽

10.1017/s0031182000070918 ◽

1966 ◽

Vol 56 (2) ◽

pp. 313-322 ◽

Cited By ~ 14

Author(s):

J. M. Webster ◽

D. Lowe

Keyword(s):

Plant Growth ◽

Callus Culture ◽

Large Population ◽

Red Clover ◽

Parasitic Nematodes ◽

Plant Parasitic Nematodes ◽

Nematode Reproduction ◽

Callus Tissues ◽

Host Parasite ◽

Plant Parasitic

Some callus tissues induced by 2,4–D and derived from plants resistant to plant-parasitic nematodes lost their resistance to the nematodes. Red clover callus supported a large population of A. ritzemabosi, whereas red clover seedlings did not. Six races of D. dipsaci were cultured on lucerne and red clover callus tissues and reproduced rapidly, although races usually multiplied more on callus from susceptible than from resistant plants. A. ritzemabosi, normally only a foliage parasite, reproduced equally well in stem and root callus. H. rostochiensis did not reproduce in callus culture.Nematodes multiplied most in callus that grew fastest; both reproduction of A. ritzemabosi and the growth of callus were greatest with 0.125 mg/1 of 2,4–D. Reproduction was inhibited by 5.0 mg/100 ml of 2,4–D. 2,4–D influenced nematode reproduction indirectly by making callus, which provides a better environment for nematode feeding and reproduction.Nematode extracts added to an agar medium caused callus formation on red clover seedlings and nematodes feeding on these tissues reproduced faster than on normal seedlings. Hence, the substances secreted by a nematode into a plant may act on the tissues in a manner similar to 2,4–D. The host–parasite relationship is probably partially controlled by the host's plant-growth substances and the effect on them of the nematode's secretions.We thank Mr C. T. Drakes for assistance, and Mr K. Smith of Imperial Chemical Industries for advice with the initial callus culture.

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From Genome to Field—Observation of the Multimodal Nematicidal and Plant Growth-Promoting Effects of Bacillus firmus I-1582 on Tomatoes Using Hyperspectral Remote Sensing

Plants ◽

10.3390/plants9050592 ◽

2020 ◽

Vol 9 (5) ◽

pp. 592

Author(s):

Nik Susič ◽

Uroš Žibrat ◽

Lovro Sinkovič ◽

Andrej Vončina ◽

Jaka Razinger ◽

...

Keyword(s):

Plant Growth ◽

Hyperspectral Imaging ◽

Control Method ◽

Parasitic Nematodes ◽

Support Vector ◽

Primary Control ◽

Bacillus Firmus ◽

Wide Range ◽

Plant Growth Promoting ◽

Growth Promoting

Root-knot nematodes are considered the most important group of plant-parasitic nematodes due to their wide range of plant hosts and subsequent role in yield losses in agricultural production systems. Chemical nematicides are the primary control method, but ecotoxicity issues with some compounds has led to their phasing-out and consequential development of new control strategies, including biological control. We evaluated the nematicidal activity of Bacillus firmus I-1582 in pot and microplot experiments against Meloidogyne luci. I-1582 reduced nematode counts by 51% and 53% compared to the untreated control in pot and microplot experiments, respectively. I-1582 presence in the rhizosphere had concurrent nematicidal and plant growth-promoting effects, measured using plant morphology, relative chlorophyll content, elemental composition and hyperspectral imaging. Hyperspectral imaging in the 400–2500 nm spectral range and supervised classification using partial least squares support vector machines successfully differentiated B. firmus-treated and untreated plants, with 97.4% and 96.3% accuracy in pot and microplot experiments, respectively. Visible and shortwave infrared spectral regions associated with chlorophyll, N–H and C–N stretches in proteins were most relevant for treatment discrimination. This study shows the ability of hyperspectral imaging to rapidly assess the success of biological measures for pest control.

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Expression of a fungal lectin in Arabidopsis enhances plant growth and resistance towards microbial pathogens and plant-parasitic nematode

10.1101/2021.01.12.426396 ◽

2021 ◽

Author(s):

Aboubakr Moradi ◽

Mohamed El-Shetehy ◽

Jordi Gamir ◽

Tina Austerlitz ◽

Paul Dahlin ◽

...

Keyword(s):

Disease Resistance ◽

Plant Growth ◽

Pseudomonas Syringae ◽

Plant Disease Resistance ◽

Plant Protection ◽

Heterodera Schachtii ◽

Parasitic Nematodes ◽

Wild Type ◽

Phytopathogenic Bacterium ◽

Plant Parasitic

AbstractCoprinopsis cinerea lectin 2 (CCL2) is a fucoside-binding lectin from the basidiomycete C. cinerea that is toxic to the bacterivorous nematode Caenorhabditis elegans as well as animal-parasitic and fungivorous nematodes. We expressed CCL2 in Arabidopsis to assess its protective potential towards plant-parasitic nematodes. Our results demonstrate that expression of CCL2 enhances host resistance against the cyst nematode Heterodera schachtii. Surprisingly, CCL2-expressing plants were also more resistant to fungal pathogens including Botrytis cinerea, and the phytopathogenic bacterium Pseudomonas syringae. In addition, CCL2 expression positively affected plant growth indicating that CCL2 has the potential to improve two important agricultural parameters namely biomass production and general disease resistance. The mechanism of the CCL2-mediated enhancement of plant disease resistance depended on fucoside-binding by CCL2 as transgenic plants expressing a mutant version of CCL2 (Y92A), compromised in fucoside-binding, exhibited wild type disease susceptibility. The protective effect of CCL2 did not seem to be direct as the lectin showed no growth-inhibition towards B. cinerea in in vitro assays. We detected, however, a significantly enhanced transcriptional induction of plant defense genes in CCL2- but not CCL2-Y92A-expressing lines in response to infection with B. cinerea compared to wild type plants. This study demonstrates a potential of fungal defense lectins in plant protection beyond their use as toxins.

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Potential for Soybean Cyst Nematode Reproduction on Winter Weeds and Cover Crops in Tennessee

Plant Health Progress ◽

10.1094/php-2007-0226-01-rs ◽

2007 ◽

Vol 8 (1) ◽

pp. 25 ◽

Cited By ~ 2

Author(s):

P. A. Donald ◽

Robert Hayes ◽

Eric Walker

Keyword(s):

Population Density ◽

Cover Crops ◽

Cover Crop ◽

Soybean Cyst Nematode ◽

Management Strategies ◽

Cyst Nematode ◽

No Tillage ◽

Nematode Reproduction ◽

Tillage Practices ◽

Crimson Clover

The soybean cyst nematode (SCN), Heterodera glycines, is a major yield limiting pest of soybean (Glycine max). Current SCN management strategies include resistant soybean varieties and rotation with non-host crops. Increased adoption of the early soybean production system (ESPS) combined with a greater incidence of winter weeds from no-tillage practices may increase the population density of SCN during the noncrop period since several winter weeds and cover crops are hosts for SCN. A field experiment with a split-strip design was conducted over three years to evaluate whether SCN reproduced on weeds and cover crops during the noncrop period. Winter weeds and crimson clover roots were examined for females and cysts with eggs. The soil was sampled to determine if an increase in SCN egg population density occurred. We found no indication of SCN reproduction on winter weeds during the noncrop period or on the cover crop crimson clover. Accepted for publication 2 November 2006. Published 26 February 2007.

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Plant Growth Promotion and Biocontrol of Pythium ultimum by Saline Tolerant Trichoderma Isolates under Salinity Stress

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph16112053 ◽

2019 ◽

Vol 16 (11) ◽

pp. 2053 ◽

Cited By ~ 3

Author(s):

Brenda Sánchez-Montesinos ◽

Fernando Diánez ◽

Alejandro Moreno-Gavira ◽

Francisco J. Gea ◽

Mila Santos

Keyword(s):

Biological Control ◽

Plant Growth ◽

Growth Promotion ◽

Biological Control Agent ◽

Dry Weight ◽

Pythium Ultimum ◽

Saline Stress ◽

Growth Promoter ◽

Plant Growth Promoting ◽

Growth Promoting

This present study evaluates three isolates of Trichoderma as plant growth promoting or biological control agents: Trichoderma aggressivum f. sp. europaeum, Trichoderma saturnisporum, and the marine isolate obtained from Posidonia oceanica, Trichoderma longibrachiatum. The purpose is to contribute to an overall reduction in pesticide residues in the fruit and the environment and to a decrease in chemical fertilizers, the excess of which aggravates one of the most serious abiotic stresses, salinity. The tolerance of the different isolates to increasing concentrations of sodium chloride was evaluated in vitro, as well as their antagonistic capacity against Pythium ultimum. The plant growth promoting capacity and effects of Trichoderma strains on the severity of P. ultimum on melon seedlings under saline conditions were also analysed. The results reveal that the three isolates of Trichoderma, regardless of their origin, alleviate the stress produced by salinity, resulting in larger plants with an air-dry weight percentage above 80% in saline stress conditions for T. longibrachiatum, or an increase in root-dry weight close to 50% when T. aggressivum f. sp. europaeum was applied. Likewise, the three isolates showed antagonistic activity against P. ultimum, reducing the incidence of the disease, with the highest response found for T. longibrachiatum. Biological control of P. ultimum by T. aggressivum f. sp. europaeum and T. saturnisporum is reported for the first time, reducing disease severity by 62.96% and 51.85%, respectively. This is the first description of T. aggressivum f. sp. europaeum as a biological control agent and growth promoter. The application of these isolates can be of enormous benefit to horticultural crops, in both seedbeds and greenhouses.

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Effect of a Neem preparation on reproduction of the nematode Globodera rostochiensis and growth of potato

Journal of Agricultural Sciences Belgrade ◽

10.2298/jas1202091t ◽

2012 ◽

Vol 57 (2) ◽

pp. 91-97

Author(s):

Zlatka Trifonova

Keyword(s):

Population Density ◽

Plant Growth ◽

Potato Tuber ◽

Globodera Rostochiensis ◽

Cyst Nematode ◽

Potato Cyst Nematode ◽

Growth And Yield ◽

Nematode Reproduction ◽

Soil Application

An experiment was conducted under glasshouse conditions to test the effects of neem-based product in the form of drenches and potato tuber treatments on the growth of potato and population density of the potato cyst nematode Globodera rostochiensis. The soil applications of the biopreparation improved the plant growth and yield of potato, being greatest with 1% Neem Azal. The biggest increase in the yield occurred in the Oxamyl application (15.8%). The biopreparation in concentrations from 0.2% to 1% increased the yield of potatoes from 0.3% to 9.7% compared to the untreated inoculated control. The soil application was relatively more effective in increasing of the yield (0.3%-9.7%) than the potato tuber treatments (0.3%-2.3%). The nematode reproduction was reduced 83.3% with Oxamyl and from 59.8% to 71.0% with Neem Azal treatments.

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