scholarly journals Dispersion of the soybean root rot by Cycloneda sanguinea (Coleoptera: Coccinellidae)

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Geraldo Salgado-Neto ◽  
Marcos André Braz Vaz ◽  
Jerson Vanderlei Carús Guedes ◽  
Marlove Fátima Brião Muniz ◽  
Elena Blume ◽  
...  
Keyword(s):  
Root Rot ◽  
2021 ◽  
Author(s):  
Xiaoli Chang ◽  
Huiting Xu ◽  
Li Yan ◽  
Dan Zhu ◽  
Wei Wang ◽  
...  

Abstract BackgroundThe dynamic of soil-borne disease is closely related to the rhizosphere microbial communities. Maize-soybean intercropping can suppress soybean root rot as compared to monoculture. However, it is still unknown whether rhizosphere microbial community participates in the regulation of intercropped soybean root rot.MethodsIn this study, the difference of rhizosphere Fusarium and Trichoderma community was compared between healthy or root-rotted soybean rhizosphere soil from soybean monoculture and maize-soybean intercropping, and the inhibitory effect of potential biocontrol Trichoderma against pathogenic Fusarium were examined.ResultsThe abundance of rhizosphere Fusarium was remarkably different between intercropping and monoculture, while Trichoderma was largely accumulated in healthy rhizosphere soil of intercropping rather than monoculture. Four rhizosphere Fusarium species identified were all pathogenic to soybean but displayed distinct composition and isolation proportion in the corresponding soil types. As the dominant and most aggressive species, F. oxysporum was more frequently isolated in diseased soil of monoculture. Furthermore, of three Trichoderma species identified, T. harzianum dramatically increased in the rhizosphere of intercropping rather than monoculture as compared to T. virens and T. afroharzianum. For in-vitro antagonism test, Trichoderma strains had antagonistic effects on F. oxysporum with the percentage of mycelial inhibition ranging of 50.59%-92.94%, and they displayed good mycoparasitic abilities against F. oxysporum through coiling around and entering into the hyphae, expanding along cell-cell lumen and even dissolving cell walls of target fungus.ConclusionThese results indicate maize-soybean intercropping significantly increase the density and composition proportion of beneficial Trichoderma to antagonist the pathogenic Fusarium species, thus contributing to the suppression of soybean root rot under intercropping.


Plant Disease ◽  
2019 ◽  
Vol 103 (6) ◽  
pp. 1435-1435
Author(s):  
Y. Li ◽  
S. Wang ◽  
Y.-K. Liu ◽  
Q.-S. Lu ◽  
K. Wang ◽  
...  

Pathogens ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 211
Author(s):  
Xiaoli Chang ◽  
Li Yan ◽  
Muhammd Naeem ◽  
Muhammad Ibrahim Khaskheli ◽  
Hao Zhang ◽  
...  

Fusarium species are the most detrimental pathogens of soybean root rot worldwide, causing large loss in soybean production. Maize/soybean relay strip intercropping has significant advantages on the increase of crop yields and efficient use of agricultural resources, but its effects on the occurrence and pathogen population of soybean root rot are rarely known. In this study, root rot was investigated in the fields of the continuous maize/soybean strip relay intercropping and soybean monoculture. Fusarium species were isolated from diseased soybean roots and identified based on sequence analysis of translation elongation factor 1α (EF-1α) and RNA polymerase II second largest subunit (RPB2), and the diversity and pathogenicity of these species were also analyzed. Our results showed that intercropping significantly decreased soybean root rot over monoculture. A more diverse Fusarium population including Fusarium solani species complex (FSSC), F. incarnatum-equiseti species complex (FIESC), F. oxysporum, F. fujikuroi, F. proliferatum and F. verticillioides, F. graminearum and F. asiaticum was identified from intercropping while FSSC, FIESC, F. oxysporum, F. commune, F. asiaticum and F. meridionale were found from monoculture. All Fusarium species caused soybean root infection but exhibited distinct aggressiveness. The most aggressive F. oxysporum was more frequently isolated in monoculture than intercropping. FSSC and FIESC were the dominant species complex and differed in their aggressiveness. Additionally, F. fujikuroi, F. proliferatum and F. verticillioides were specifically identified from intercropping with weak or middle aggressiveness. Except for F. graminearum, F. meridionale and F. asiaticum were firstly reported to cause soybean root rot in China. This study indicates maize/soybean relay strip intercropping can reduce soybean root rot, change the diversity and aggressiveness of Fusarium species, which provides an important reference for effective management of this disease.


2013 ◽  
Vol 93 (2) ◽  
pp. 221-236 ◽  
Author(s):  
J. X. Zhang ◽  
A. G. Xue ◽  
E. R. Cober ◽  
M. J. Morrison ◽  
H. J. Zhang ◽  
...  

Zhang, J. X., Xue, A. G., Cober, E. R., Morrison, M. J., Zhang, H. J., Zhang, S. Z. and Gregorich, E. 2013. Prevalence, pathogenicity and cultivar resistance of Fusarium and Rhizoctonia species causing soybean root rot. Can. J. Plant Sci. 93: 221–236. Root rot complex, caused by Fusarium and Rhizoctonia species, is a major soybean disease in Canada. We isolated nine Fusarium and Rhizoctonia species including F. oxysporum (Fo), F. graminearum (Fg), F. solani (Fs), F. avenaceum (Fa), F. tricinctum (Ft), F. sporotrichioides (Fsp), F. equiseti (Fe), F. poae (Fp), and R. solani (Rs) from soybean roots in eastern Ontario, Canada. The isolation results indicated that Fo was the most prevalent species while Fa, Fsp, and Fp were the least frequent species in the soybean rhizosphere. Numbers of Fo, Fs, Fg, and Rs isolates recovered from adult plant roots were significantly greater than those from seedling roots (P<0.01). The Rs, Fg and Fsp isolates were significantly more abundant in the no-till field than in the tilled field (P<0.01). Based on the greenhouse assays, Rs, Fg, and Fa were the most pathogenic species, while Fe and Fsp were the least pathogenic to soybean. The field resistance evaluation, based on the root rot severity, identified 21, 17, 30, and 3 out of 70 cultivars among the most tolerant to Fg, Fo, Fs, and Rs, respectively. A few of the cultivars showed partial resistance to multiple species, based on root rot severity and reduction in their seedling emergence, plant height, and root dry weight, but no cultivar was found to partially resist all four species. There was no correlation (P>0.05) between root rot severity and the reduction in seedling emergence, plant height, or root dry weight.


2021 ◽  
Vol 26 (02) ◽  
pp. 287-293
Author(s):  
Fan Yang

Soybean root rot is a worldwide soil-borne fungal disease threatening soybean production, causing huge losses in yield and quality of soybean. Fusarium species are well recognized as the important causal agent of Fusarium root rot. To screen the beneficial Bacillus strains with capability of suppressing soybean root rot and evaluate the impact of Bacillus combined with biochar against soybean root rot, a pot experiment was conducted with different treatments. In this study, as potential biological control measures, antagonistic Bacillus isolates and different types of biochar were added to soil separately and excellent antagonistic strains mixed with bamboo biochar were applied to the soil. The results showed that seven Bacillus strains promoted the growth of soybean seedlings and reduced root rot severity by 33 to 61%. Bacillus amylolique faciens NH2 was associated with the lowest incidence of soybean root rot, indicating its bio-control potential. The value of plant height, root length and plant dry weight of soybean in the sterilized soil mixed with biochar separately treatment were superior to those of soybean in the inoculated with pathogen treatment, especially the bamboo biochar treatment reduced soybean root rot caused by Fusarium significantly and which bio-control efficacy was 77.41%. The soybean plants shoot and root dry weights in the biochar mixed B. amylolique faciens NH2 or B. subtilis DBK treatments were increased by17.1, 10.7% and 19.51, 19.64%, respectively, which were significantly higher than those of the inoculated pathogen treatment. Compared to antagonistic strain or biochar individual treatments, the disease control efficiency on soybean root rot was up to 64.86% in NH2 strain mixed with bamboo biochar treatment, which reduced root rot severity significantly and showed a synergistic effect. These results suggest that antagonistic Bacillus strains mixed with biochar can be used as an effective alternative in managing soybean root rot. © 2021 Friends Science Publishers


Plant Disease ◽  
2021 ◽  
Author(s):  
Shuang Wang ◽  
Xinmin Li ◽  
Chunlai Liu ◽  
Liang Liu ◽  
Fan Yang ◽  
...  

In August 2017, soybean root rot plants exhibiting root rot were observed in Baiquan County (47°60′N, 126°10′E), Heilongjiang province, China. The disease occurred on approximately 65% of soybean (cv. Heihe43) plantsroots in five fields (>10 ha). The disease resulted in yellowing or wilting and smaller sized leaves, absence of lateral roots and black lesions on tap roots. Infected root tissues from 10 individual plants (2 plants/each field) were surface disinfested with 0.5% NaOCl for 2 min, rinsed three times in sterile distilled water, placed on potato dextrose agar PDA, and incubated at 26℃ for 3 days. Eight fungal isolates were obtained by transferring hyphal tips.isolated and subcultured by transferring hyphal tips. Colonies on PDA were initially white to rose, then yellow in color with abundant aerial mycelium. The fungal colonies grew to a size of 7.4 cm in diameter four days after inoculation. Macroconidia were scarce and scattered, measuring 19.7 μm× 3.5 μm (n = 50) on carnation leaf agar. Typical macroconidium had 3-5 septa, slightly sharp apices with a distinct basal foot cell. Microconidia had 0-2 septa, and were slightly curved, measuring 10.7 μm × 3.2 μm (n = 50). Spherical chlamydospores had a mean diameter of 13.7μm (n = 50), were terminal and intercalary on PDA. According to these morphological characteristics, the fungus was identified as F. brachygibbosum (Padwick1945). Genomic DNA of a representative isolate P13-1was extracted. The Ef-1α, RPB1 and RPB2 regions were amplified using primers ef1/ef2, Fa/G2R and 5f2/7cr (O’Donnell et al. 2010).The consensus sequences (accession nos. MH748277, MH748278 and MH748279) showed 98.65%, 98.91% and 99.54% identity to the sequences of F. brachygibbosum strain NRRL 34033(accession no.GQ505418.1, HM347172.1 and GQ505482.1). Isolate P13-1was preserved in Agricultural Culture Collection of China, Stock ID number is ACCC 39715.To confirm pathogenicity of P13-1, soybean (cv. Heihe43) seeds were grown in 15-cm pots containing a commercial potting mix (5seeds per pot,3 pots/ treatment). Sorghum seeds (10 g) fully colonized by F. brachygibbosum (Li et al., 2018)were uniformly distributed in each pot and then covered with a 0.5-cm layer of sterile potting soil. , Sterilized sterilized sorghum seeds(10 g) were added to control pots. , incubated in a growth chamber at 25°C (12h day) / 20°C (12h night). 10 Ten days after inoculation , all inoculated plants showed symptoms consistent with those observed in the fields. The experiment was repeated two times. F. brachygibbosum was reisolated from diseased plants and identified as F. brachygibbosum based on morphological and gene sequences analysismolecular characteristics. No fungal pathogens were isolated from nontreated controls. To our knowledge, this is the first report of F. brachygibbosum on soybean in China. The soybean is the prime oil seed crop and the source of protein cultivated in Northeast China and this disease seriously affects the seedling growth. So, our findings are very important for the establishment of control strategies and breeding for resistance to soybean root rot.


Sign in / Sign up

Export Citation Format

Share Document