scholarly journals Induction of Beet-Cyst Nematode Suppressiveness by the Fungi Dactylella oviparasitica and Fusarium oxysporum in Field Microplots

2006 ◽  
Vol 96 (8) ◽  
pp. 855-859 ◽  
Author(s):  
Rabiu Olatinwo ◽  
James Borneman ◽  
J. Ole Becker

The ability of Dactylella oviparasitica and Fusarium oxysporum to suppress Heterodera schachtii numbers was examined in field microplots. Fungi were individually added to fumigated field soil that was seeded with sugar beet. Four weeks later, soils were infested with H. schachtii second-stage juveniles (J2). At two harvests, 11 weeks and 19 weeks (1,469 and 2,547 degree days (base 8°C), respectively) after nematode-infestation, H. schachtii cyst and egg numbers were assessed. At both time points, D. oviparasitica reduced H. schachtii population densities to those in the naturally suppressive soil, even when additional H. schachtii J2 were added to the microplots after the first harvest. Although F. oxy-sporum did not alter H. schachtii population densities after 11 weeks, significant reductions were detected after 19 weeks. The sustainability of the H. schachtii suppressiveness created by single applications of the fungi at the beginning of the microplot trials was further examined in a greenhouse study. Soil collected at the completion of the microplot trials was potted and seeded with sugar beet. Four weeks later, each pot was infested with H. schachtii J2. Approximately 16 weeks (1,389 degree days) after seeding, the D. oviparasitica-amended soil produced greater fresh root weights and considerably smaller nematode population densities than the nonamended control.

Agronomy ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 355
Author(s):  
Daub Matthias

The integration of oilseed rape (OSR) into sugar beet rotation systems is restricted due to the very good host status of OSR for the beet cyst nematode (BCN) Heterodera schachtii. In contrast to sugar beet, the cultivation of winter OSR covers a longer period, but at a lower soil temperature regime. Thus, presumably one or two generations of BCN may develop during the cultivation of winter OSR, resulting in moderate multiplication rates of 1–2 in the present study. This multiplication rate was year-dependent, but not affected by different sowing times. For the first time, the present study identified volunteer OSR emerging in high densities post-harvest as a major risk for a high multiplication of BCN at optimum temperatures. The emergence of BCN females with offspring was observed very early, resulting in a significant population increase before 350-degree days (>8 °C) in inoculation experiments and in field investigations. Conducting treatment trials with glyphosate to control volunteer OSR in micro-plots and field experiments confirmed effective suppression of BCN reproduction when growth of volunteer OSR was interrupted at 250–350-degree days. Thus, data gained from BCN reproduction studies under controlled and field conditions provided a unique basis for the development of a trap crop method. The degree day model has been successfully implemented as part of an open access management tool.


2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Razieh Ghaemi ◽  
Ebrahim Pourjam ◽  
Naser Safaie ◽  
Bruno Verstraeten ◽  
Seyed Bagher Mahmoudi ◽  
...  

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.


Nematology ◽  
2001 ◽  
Vol 3 (6) ◽  
pp. 551-558 ◽  
Author(s):  
Andreas Westphal ◽  
J. Ole Becker

AbstractHeterodera schachtii population densities were monitored in a H. schachtii -suppressive soil cropped in screenhouse experiments for two consecutive seasons with wheat, susceptible or resistant cultivars of either sugar beet or oilseed radish, or left fallow. Heterodera schachtii population densities under wheat and the resistant cultivars of sugar beet and oilseed radish did not differ significantly from the fallow treatment. Populations declined under all crops, with a reproductive factor between 0.08 and 0.57. In glasshouse experiments, introduced H. schachtii populations increased greatly on susceptible Swiss chard grown in previously wheat-monocultured soils, suggesting that significant loss of H. schachtii suppressiveness occurred during the monoculture. Following fallow, two H. schachtii-resistant or two H. schachtii-susceptible cultivars, introduced sugar beet cyst nematode populations remained small, suggesting that suppressiveness had been maintained. In a field trial with H. schachtii suppressive soil, cyst nematode population densities remained lower under wheat, resistant sugar beet, resistant radish and susceptible radish than under susceptible sugar beet.


2021 ◽  
pp. 394-399
Author(s):  
Matthias Daub

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.


Nematology ◽  
2008 ◽  
Vol 10 (6) ◽  
pp. 919-924 ◽  
Author(s):  
Mansour Salati ◽  
Robert Riggs ◽  
Zahra Tanha Maafi

AbstractThe soybean cyst nematode (SCN), Heterodera glycines, found in most soybean growing regions in the world, is considered the most economically damaging pathogen of soybean worldwide. A survey conducted in the northern provinces of Mazandaran and Golestan, the main soybean-producing areas in Iran, revealed SCN was widespread in different localities of these regions. Of the 55 and 88 soil samples collected from soybean fields in Mazandaran and Golestan provinces, respectively, ten (18.8%) and 23 (26%) samples were infested with H. glycines; the population densities of second-stage juveniles (J2) and eggs ranged from 500 to 60 000 and 500 to ≥100 000 per 250 cm3 soil, respectively. These population densities of H. glycines are indicative of reductions in soybean yield. HG Type tests were conducted on 16 field populations. HG Type 0 (race 3) was the most common with 94% frequency, whereas HG Type 7 (race 6) was found in 6% of tested populations. Most populations of H. glycines parasitised PI88788 and PI548316. Eight of the most commonly used soybean cultivars were tested against H. glycines HG Type 0; seven of them, Sepideh, Sahar (Pershing), Gorgan 3, Williams 82, JK (Sari), BP (Telar) and Hill, had high female indices and were considered susceptible to HG Type 0. Only the cultivar DPX showed low female indices and was resistant to race 3. The initial observations showed that the first life cycle of SCN required 30-34 days in early-planted fields (late May and early June), whereas in late-planted fields (early July), white females were visible 20 days after planting. Several generations could be expected in a single growing season under field conditions in northern Iran.


2006 ◽  
Vol 96 (1) ◽  
pp. 111-114 ◽  
Author(s):  
Rabiu Olatinwo ◽  
Bei Yin ◽  
J. Ole Becker ◽  
James Borneman

This study examined the role of the fungi Dactylella oviparasitica and Fusarium oxysporum in the beet-cyst nematode (Heterodera schachtii) suppressiveness exhibited by a southern Californian soil. In prior research, the abundance of D. oviparasitica rRNA genes positively correlated with high levels of suppressiveness, whereas the abundance of F. oxysporum rRNA genes positively correlated with minimal to moderate levels of suppressiveness. In this report, both fungi were added to fumigation-induced nonsuppressive soil, planted with Swiss chard, and infested with H. schachtii juveniles. After two nematode generations, D. oviparasitica strain 50 reduced the population densities of H. schachtii eggs and juveniles to those in the suppressive soil and H. schachtii cysts to levels lower than in the suppressive soil. F. oxysporum did not significantly reduce H. schachtii populations. These results suggest that D. oviparasitica strain 50 plays a major role in the suppression of H. schachtii population development in this southern Californian soil.


2009 ◽  
Vol 49 (1) ◽  
pp. 27-34 ◽  
Author(s):  
Parisa Palizi ◽  
E. Goltapeh ◽  
Ebrahim Pourjam ◽  
Naser Safaie

Potential of Oyster Mushrooms for the Biocontrol of Sugar Beet Nematode (Heterodera Schachtii)The potential of oyster mushrooms to attack and kill sugar beet cyst nematode (Heterodera schachtii) was studied. The ability ofPleurotus ostreatus, P. sajor-caju, P. florida, P. flabellatus, P. ostreatus(sporeless),P. eryngiiandHypsizygus ulmariusto prey on the cyst nematode was confirmed. Nematodes were inoculated on water agar plates on which a single sparse fungal colony of one of the above mentioned fungi was grown. Nematodes were quickly immobilized after inoculation the plates with eachPleurotusspecies, with mortality of about 96%, 72%, 55%, 52%, 20%, 23% and 62%, respectively. Nematicidal activities of culture filtrates ofPleurotusspecies andH. ulmariusagainstH. schachtiiwere also studiedin vitro.Extracts ofP. ostreatuscould paralyse 90% of nematodes whereasP. eryngiicould paralyse only 50% of nematodes. The efficacy of old mushroom compost from cultures ofP. ostreatusandP. sajor-cajuin controlling cysts on sugar beet (Beta vulgarisICI) were studied under greenhouse conditions. The results showed that 100 and 200 grams of mushroom compost per 3 kilogram/pot could significantly control cysts, reducing more than 85% cysts in soil. Presence of cysts on the roots and larvae inside roots were compared with the control treatment.


Life ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1358
Author(s):  
Chen Jiang ◽  
Yingdong Zhang ◽  
Ke Yao ◽  
Sulaiman Abdulsalam ◽  
Guangkuo Li ◽  
...  

Sugar beet cyst nematode (SBCN, Heterodera schachtii) is an important nematode that causes significant yield losses of 25–50% or more in most areas of sugar beet production worldwide. Rapid and accurate identification of this species is essential to support decisions on pest management. However, the difference between H. schachtii and other Heterodera spp. based on morphology is a challenging task. In the present study, a SCAR-PCR assay was developed to identify and differentiate H. schachtii in infected root and soil samples. H. schachtii-species-specific SCAR-PCR primers OPA06-HsF and OPA06-HsR were designed from the randomly amplified polymorphic DNA (RAPD) marker amplified with random primer OPA06. The developed primers specifically amplify a 922-bp fragment from the target populations but did not amplify DNA from non-target cyst nematodes including Heterodera, Globodera, Cactodera, and other related species tested in this study. The sensitivity detection indicated that 5 × 10−4 of a single cyst, 1/320 of a single second-stage juvenile (J2), or 10 pg of genomic DNA could be detected. The assay accurately identifies the different stages of H. schachtii in sugar beet and oilseed rape roots as well as a single J2 in 10 g of soil. Finally, the SCAR-PCR assay detected H. schachtii in seven samples out of the fifteen field samples. The assay will not only be useful for differentiating H. schachtii from mixed populations of Heterodera spp. but also for effective detection of the species directly from infested samples. The assay also requires no expertise in the taxonomy and morphology of the species but serves to improve the diagnosis of H. schachtii in infested fields.


Sign in / Sign up

Export Citation Format

Share Document