Heterologous expression of a polyketide synthase ACRTS2 in Aspregillus oryzae produces host selective ACR-toxins: Co-production of minor metabolites

2021 ◽  
Author(s):  
Akari Kotani ◽  
Taro Ozaki ◽  
Junya Takino ◽  
Susumu Mochizuki ◽  
Kazuya Akimitsu ◽  
...  
Keyword(s):  
Detection Limit ◽  
Structure Determination ◽  
Leaf Spot ◽  
Polyketide Synthase ◽  
Kojic Acid ◽  
Direct Production ◽  
The Core ◽  
Rough Lemon ◽  
Brown Leaf Spot ◽  
Brown Leaf

Abstract Previously, we succeeded to produce the core structure of the host-selective ACR-toxin (1) on brown leaf spot on rough lemon when the polyketide synthase ACRTS2 gene was heterologously expressed in Aspergillus oryzae (AO). To confirm the production of 1 in AO, the detection limit and suppressing decarboxylation were improved, and these efforts led us to conclude the direct production of 1 instead of its decarboxylation product. During this examination, minor ACR-toxin-related metabolites were found. Their structure determination enabled us to propose a decarboxylation mechanism and novel branching route forming byproducts from the coupling of the dihydropyrone moiety of 1 with the acetaldehyde and kojic acid abundant in AO. The involvement of putative cyclase ACRTS3 in the chain release of linear polyketide was excluded by the co-expression analysis of ACRTS2 and ACRTS3. Taken together, we concluded the production of 1 in AO is solely responsible for ACRTS2.

Recurrent Phenotypic Selection for Resistance to Brown Leaf Spot in Smooth Bromegrass 1

Crop Science ◽  
1986 ◽  
Vol 26 (3) ◽  
pp. 533-536 ◽  
Author(s):  
Clyde C. Berg ◽  
Robert T. Sherwood ◽  
Kenneth E. Zeiders
Keyword(s):  
Leaf Spot ◽  
Phenotypic Selection ◽  
Smooth Bromegrass ◽  
Brown Leaf Spot ◽  
Brown Leaf ◽  
Selection For

scholarly journals Bipolaris oryzae Causing Brown Leaf Spot on Echinochloa crus-galli in Southern Brazil

Plant Disease ◽  
2019 ◽  
Vol 103 (5) ◽  
pp. 1038 ◽  
Author(s):  
T. E. Kaspary ◽  
C. Bellé ◽  
C. A. G. Rigon ◽  
L. Cutti ◽  
G. Casarotto ◽  
...  
Keyword(s):  
Leaf Spot ◽  
Southern Brazil ◽  
Bipolaris Oryzae ◽  
Brown Leaf Spot ◽  
Brown Leaf

Pseudocercospora timorensis. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
S. Little
Keyword(s):  
Sweet Potato ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Ipomoea Batatas ◽  
Leaf Surface ◽  
Solomon Islands ◽  
Leaf Spots ◽  
Brown Leaf Spot ◽  
Water Splash ◽  
Brown Leaf

Abstract A description is provided for Pseudocercospora timorensis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Ipomoea batatas (sweet potato), I. biloba, I. campanulata, I. cordofana, I. muricata, I. peltata, I. setifera.DISEASE: Leaf spot or brown leaf spot of sweet potato. Small circular lesions first form on the leaf borders and tips before spreading over the leaf surface. These leaf spots enlarge becoming brown to dark brown in colour with a verruculose surface. The larger leaf veins may delimit the spots. GEOGRAPHICAL DISTRIBUTION: Africa: most countries; Asia: Hong-Kong, India, Indonesia, Malaysia, Taiwan; Australasia: Fiji, Papua New Guinea, Solomon Islands; North America: West Indies (St Lucia). TRANSMISSION: Presumably by wind-borne and water-splash dispersed conidia.

scholarly journals Eco-Friendly Management of Rice Diseases

2015 ◽  
Vol 3 (1) ◽  
pp. 80-88 ◽  
Author(s):  
Md. Amanut Ullah Razu ◽  
Ismail Hossain
Keyword(s):  
Leaf Spot ◽  
Leaf Extract ◽  
Sheath Blight ◽  
Leaf Blight ◽  
Bacterial Leaf Blight ◽  
Curvularia Lunata ◽  
Brown Leaf Spot ◽  
Brown Leaf ◽  
Clove Extract ◽  
Field And Laboratory Conditions

Comparative efficacy of BAU-Biofungicide (2%), a product of Trichoderma harzianum, Garlic (Allium sativum) clove extract (5%), Allamanda(Allamanda cathartica) leaf extract (5%), Bion (25ppm), Amistar (0.1%) and Tilt 250EC (0.1%) were evaluated for eco-friendly managementof diseases of rice cv. BRRI Dhan-49 under field and laboratory conditions from July,2013 to March,2014. The field experiment was carriedout following Randomised Complete Block Design and the laboratory experiments were done following Completely Randomized Design.Brown spot, Narrow brown leaf spot, Bacterial leaf blight and Sheath blight were recorded in the field. The lowest incidence of brown spotand narrow brown leaf spot was observed in plots treated with BAU-Biofungicide and that of bacterial leaf blight was observed in plots sprayedwith Allamanda leaf extract. In case of sheath blight, the lowest incidence was observed in BAU-Biofungicide sprayed plots. The highest grainyield (3680.34kg/ha) was recorded in plots sprayed with BAU-Biofungicide which is 40.56% higher over control. The highest seed germination(%) was recorded when seeds were treated with Garlic clove extract (89.29%) followed by BAU-Biofungicide (87.30%). The prevalence ofseed-borne fungi was investigated by blotter method. The identified seed-borne fungal species were Bipolaris oryzae, Fusarium oxysporum,Fusarium moniliforme, Curvularia lunata, Aspergillus niger and Aspergillus flavus. Maximum reduction of seed-borne infection of pathogenswas obtained by treating seeds with BAU-Biofungicide (2% of seed weight).DOI: http://dx.doi.org/10.3126/ijasbt.v3i1.11977    Int J Appl Sci Biotechnol, Vol. 3(1): 80-88 

scholarly journals Characterization of Pyrenophora Species Causing Brown Leaf Spot on Italian Ryegrass (Lolium multiflorum) in Southwestern China

Plant Disease ◽  
2020 ◽  
Vol 104 (7) ◽  
pp. 1900-1907
Author(s):  
Longhai Xue ◽  
Yong Liu ◽  
Su Zhou ◽  
James F. White ◽  
Chunjie Li
Keyword(s):  
Leaf Spot ◽  
Disease Incidence ◽  
Lolium Multiflorum ◽  
Morphological Characteristics ◽  
Italian Ryegrass ◽  
Large Area ◽  
Internal Transcribed Spacer Region ◽  
Brown Leaf Spot ◽  
Brown Leaf ◽  
Pathogenicity Tests

Drechslera leaf spot (DLS) caused by Pyrenophora (Drechslera) species is one of the most serious diseases affecting Italian ryegrass (Lolium multiflorum) in China. Between 2015 and 2018, this disease was observed in three Italian ryegrass fields in the province of Sichuan, China. Average leaf disease incidence was approximately 1 to 12% but could range up to 100%. Symptoms appeared as brown or tan spots surrounded by a yellow halo, or brown to dark brown net blotch; subsequently, spots increased in number and size, and they later covered a large area of leaf, eventually causing leaf death. In this study, 86 strains of Pyrenophora fungi were isolated from leaf lesions of Italian ryegrass. Coupled with phylogenetic analysis of the internal transcribed spacer region, partial 28S ribosomal RNA gene, and glyceraldehyde-3-phosphate dehydrogenase gene, morphological characteristics showed that Pyrenophora dictyoides and P. nobleae are associated with Italian ryegrass in southwest China. Pathogenicity tests confirmed that both species can infect Italian ryegrass, causing leaf spot, whereas the virulence of the two species differed; P. nobleae showed lower pathogenicity to Italian ryegrass. This is the first time that these two Pyrenophora species were formally reported on Italian ryegrass based on both morphological and molecular characters. Overall, this study improves knowledge of the Pyrenophora species associated with Italian ryegrass and provides a foundation for control of this disease in the future.

scholarly journals First report of Nigrospora oryzae causing brown leaf spot on Mentha spicata

2020 ◽  
Vol 102 (4) ◽  
pp. 1281-1281
Author(s):  
Khadijeh Farid ◽  
Doustmorad Zafari ◽  
Mohammad Javad Soleimani ◽  
Shima Bagherabadi
Keyword(s):  
Leaf Spot ◽  
Mentha Spicata ◽  
First Report ◽  
Brown Leaf Spot ◽  
Brown Leaf ◽  
Nigrospora Oryzae
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