Characterization of wheat-Thinopyrum bessarabicum genetic stock for stripe rust and Karnal bunt resistance / Caracterização do estoque genético de trigo-Thinopyrum bessarabicum para resistência de ferrugem e Karnal bunt

Abstract Utilization of modern breeding techniques for developing high yielding and uniform plant types ultimately narrowing the genetic makeup of most crops. Narrowed genetic makeup of these crops has made them vulnerable towards disease and insect epidemics. For sustainable crop production, genetic variability of these crops must be broadened against various biotic and abiotic stresses. One of the ways to widen genetic configuration of these crops is to identify novel additional sources of durable resistance. In this regard crops wild relatives are providing valuable sources of allelic diversity towards various biotic, abiotic stress tolerance and quality components. For incorporating novel variability from wild relative's wide hybridization technique has become a promising breeding method. For this purpose, wheat-Th. bessarabicum amphiploid, addition and translocation lines have been screened in field and screen house conditions to get novel sources of yellow rust and Karnal bunt resistant. Stripe rust screening under field conditions has revealed addition lines 4JJ and 6JJ as resistant to moderately resistant while addition lines 3JJ, 5JJ, 7JJ and translocation lines Tr-3, Tr-6 as moderately resistant wheat-Thinopyrum-bessarabicum genetic stock. Karnal bunt screening depicted addition lines 5JJ and 4JJ as highly resistant genetic stock. These genetic stocks may be used to introgression novel stripe rust and Karnal bunt resistance from the tertiary gene pool into susceptible wheat backgrounds.

Resumo A utilização de técnicas modernas de melhoramento para o desenvolvimento de tipos de plantas uniformes e de alto rendimento, em última análise, estreitando a composição genética da maioria das culturas. A composição genética restrita dessas plantações tornou-as vulneráveis a doenças e epidemias de insetos. Para uma produção agrícola sustentável, a variabilidade genética dessas culturas deve ser ampliada contra vários estresses bióticos e abióticos. Uma das maneiras de ampliar a configuração genética dessas culturas é identificar novas fontes adicionais de resistência durável. A esse respeito, os parentes selvagens das culturas estão fornecendo fontes valiosas de diversidade alélica para vários componentes de qualidade e tolerância ao estresse abiótico e biótico. Para incorporar a nova variabilidade da ampla técnica de hibridização de parente selvagem tornou-se um método de reprodução promissor. Para esse efeito, trigo-Th. As linhas anfiploides, de adição e translocação de bessarabicum foram selecionadas em condições de campo e de casa de tela para obter novas fontes de ferrugem amarela e resistência ao bunt de Karnal. A triagem de ferrugem em faixas em condições de campo revelou as linhas de adição 4JJ e 6JJ como resistentes a moderadamente resistentes, enquanto as linhas de adição 3JJ, 5JJ, 7JJ e as linhas de translocação Tr-3, Tr-6 como estoque genético de trigo-Thinopyrum bessarabicum moderadamente resistente. A triagem Karnal bunt descreveu as linhas de adição 5JJ e 4JJ como estoque genético altamente resistente. Esses estoques genéticos podem ser usados para introgressão da nova ferrugem e resistência ao bunt de Karnal do pool genético terciário em origens de trigo suscetíveis.

Status quo of and challenges for research on rust disease in medicinal plants / 中国中药杂志

Medicinal plants are beneficial to human health. However,most of the major producing regions of medicinal plants suffer from rust disease,which threatens the yield and quality of Chinese medicinal materials,thus causes huge economic loss,and hinders the sustainable development of the Chinese medicine industry. By the end of 2020,rust disease had been reported in medicinal plants of 76 species and 33 families. In the 76 species,79 rust pathogens were detected. The majority of these pathogens belonged to Puccinia( 33,39. 24%),Coleosporium( 14,15. 19%),and Aecidium( 11,13. 92%). Of these 79 rust pathogens,10 were autoecious and 13 were heteroecious. Through literature research,this study reviewed the symptoms,pathogen species,severity and distribution,prevalence and occurrence conditions,and control measures of rust disease in medicinal plants,and thereby summarized the research status of rust disease in medicinal plants and the gap with other plants,which is expected to serve as a reference for further research on rust disease in medicinal plants.

Discovery and functional verification of endogenous glucanases for scleroglucan hydrolysis in Sclerotium rolfsii / 生物工程学报

Scleroglucan is a high-molecular water-soluble microbial exopolysaccharide and mainly applied in the fields of petroleum, food, medicine and cosmetics. The high molecular weight of scleroglucan produced by microbial fermentation leads to low solubility, high viscosity and poor dispersibility, thus bringing a series of difficulties to extraction, preservation and application. It is important to explore suitable degradation method to adjust the molecular weight of scleroglucan for expanding its industrial application. Taking Sclerotium rolfsii WSH-G01 as a model strain, in which functional annotations of the glucanase genes were conducted by whole genome sequencing. Based on design of culture system for culture system for differential expression of β-glucanase, endogenous β-glucanase genes in S. rolfsii WSH-G01 were excavated by transcriptomics analysis. Functions of these potential hydrolases were further verified. Finally, 14 potential endogenous hydrolase genes were obtained from S. rolfsii. After heterologous overexpression in Pichia pastoris, 10 soluble enzymes were obtained and 5 of them had the activity of laminarin hydrolysis by SDS-PAGE and enzyme activity analysis. Further investigation of the 5 endogenous hydrolases on scleroglucan degradation showed that enzyme GME9860 has positive hydrolysis effect. The obtained results provide references not only for obtaining low and medium molecular weight of scleroglucan with enzymatic hydrolysis, but also for producing different molecular weight of scleroglucan during S. rolfsii fermentation process with metabolic engineering.

Polycyclic aromatic hydrocarbons degradation by marine-derived basidiomycetes: optimization of the degradation process

ABSTRACT Pyrene and benzo[a]pyrene (BaP) are high molecular weight polycyclic aromatic hydrocarbons (PAHs) recalcitrant to microbial attack. Although studies related to the microbial degradation of PAHs have been carried out in the last decades, little is known about degradation of these environmental pollutants by fungi from marine origin. Therefore, this study aimed to select one PAHs degrader among three marine-derived basidiomycete fungi and to study its pyrene detoxification/degradation. Marasmiellus sp. CBMAI 1062 showed higher levels of pyrene and BaP degradation and was subjected to studies related to pyrene degradation optimization using experimental design, acute toxicity, organic carbon removal (TOC), and metabolite evaluation. The experimental design resulted in an efficient pyrene degradation, reducing the experiment time while the PAH concentration applied in the assays was increased. The selected fungus was able to degrade almost 100% of pyrene (0.08 mg mL-1) after 48 h of incubation under saline condition, without generating toxic compounds and with a TOC reduction of 17%. Intermediate metabolites of pyrene degradation were identified, suggesting that the fungus degraded the compound via the cytochrome P450 system and epoxide hydrolases. These results highlight the relevance of marine-derived fungi in the field of PAH bioremediation, adding value to the blue biotechnology.

Phenotypic plasticity of the basidiomata of Thelephora sp. (Thelephoraceae) in tropical forest habitats

Phenotypic plasticity in macroscopic fungi has been poorly studied in comparison to plants or animals and only general aspects of these changes have been described. In this work, the phenotypic variation in the basidiomata of Thelephora sp. (Thelephoraceae) was examined, as well as some aspects of its ecology and habitat, using 24 specimens collected in the tropical forests of the Chamela Biological Station, Jalisco, Mexico. Our observations showed that this taxon has clavarioid basidiomata that can become resupinate during development and growth if they are in contact with rocks, litter or live plants, establishing in the latter only an epiphytic relationship. This tropical species may form groups of up to 139 basidiomata over an area of 32.2m2, and in both types of vegetation (tropical sub-evergreen and deciduous forest) were primarily located on steep (>20°) South-facing slopes. It is found under closed canopy in both tropical forests, but its presence in sub-evergreen forests is greater than expected.

La plasticidad fenotípica en hongos macroscópicos ha sido poco estudiada en comparación con la de plantas o animales y solo se conocen aspectos generales de estos cambios. En este trabajo se examinó la variación fenotípica en los basidiomas de una especie de Thelephora sp. (Thelephoraceae), así como algunos aspectos de su ecología y hábitat a partir del estudio de 24 ejemplares recolectados en bosques tropicales de la Estación de Biología de Chamela, Jalisco, México. Nuestras observaciones mostraron que este taxon presenta basidiomas en forma clavarioide, los cuales pueden modificarse a resupinados si en su proceso de desarrollo se interponen obstrucciones físicas como rocas, restos vegetales o plantas vivas, estableciendo en estas últimas solo una relación epifítica. Esta especie llega a formar conjuntos de hasta 139 basidiomas en un área de 32.2m2; con localización predominante en laderas orientadas hacia el sur, de pendientes mayores a 20°, bajo doseles cerrados y con presencia mucho más significativa de lo esperado en el bosque tropical subperennifolio.

Xanthophyllomyces dendrorhous (Phaffia rhodozyma) on stromata of Cyttaria hariotii in northwestern Patagonian Nothofagus forests

The occurrence and distribution of Xanthophyllomyces dendrorhous associated with Cyttaria hariotii parasitizing three Nothofagus species (N. dombeyi, N. antarctica and N. pumilio) in northwestern Patagonia (Argentina), as well as the factors that may affect this distribution were herein studied. Between 2000 and 2007, samples were obtained from 18 different locations. Based on physiological tests and morphological characteristics of sexual structures, 72 isolates were identified as X. dendrorhous. Representative strains were studied by MSP-PCR fingerprinting and sequence analysis of the ITS region. MSP-PCR fingerprints were similar for the newly isolated strains, and were also identical to the profiles of the strains previously found in this region. Patagonian strains appear to be a genetically uniform and distinct population, supporting the hypothesis that the association with different host species has determined genetically distinct X. dendrorhous populations worldwide. X. dendrorhous was recovered from N. dombeyi and N. antarctica. Approximately half the sampling sites and samples were positive for X. dendrorhous, but the isolation recovery rate was low. X. dendrorhous was absent in the early stages of ascostromata maturation, becoming more abundant in later stages. The present work represents a step forward in the understanding of the natural distribution and ecology of this biotechnologically relevant yeast.

Xanthophyllomyces dendrorhous (Phaffia rhodozyma) asociado a estromas de Cyttaria hariotii en bosques de Nothofagus en el noroeste de la Patagonia. Se estudió la ocurrencia y la distribución de Xanthophyllomyces dendrorhous asociado a Cyttaria hariotii en tres especies de Nothofagus (N. dombeyi, N. antarctica y N. pumilio) del noroeste de la Patagonia (Argentina), y los factores que podrían afectar esta distribución. El muestreo se realizó entre 2000 y 2007 en 18 sitios diferentes. Según las pruebas fisiológicas y las características morfológicas de las estructuras sexuales, 72 de los aislamientos obtenidos se identificaron como X. dendrorhous. Se estudiaron cepas representativas mediante la técnica de MSP-PCR fingerprinting y secuenciación de la región ITS. Los perfiles de MSP-PCR fueron similares, tanto entre los nuevos aislamientos como entre estos y los de cepas previamente obtenidas en la región. Aparentemente, las cepas patagónicas forman una población genéticamente uniforme y distinta de otras poblaciones. Esto apoya la hipótesis de que la asociación con diferentes especies hospedadoras ha determinado la diferenciación genética de X. dendrorhous en todo el mundo. X. dendrorhous se recuperó de N. dombeyi y de N. antarctica. Aproximadamente la mitad de los sitios de muestreo y de muestras fueron positivos para X. dendrorhous, pero la tasa de aislamiento fue muy baja. X. dendrorhous está ausente en estadios tempranos de maduración de ascostromas y se hace más abundante en estadios más tardíos. El presente trabajo contribuye al mejor entendimiento de la distribución natural y la ecología de esta levadura, de relevancia biotecnológica.

Filogenia de hongos roya (Uredinales) en la zona andina colombiana mediante el uso de secuencias del ADN ribosomal 28S

Phylogenetic analysis of rust fungi (Uredinales) from the Colombian Andean region using 28S ribosomal DNA sequences. Rust fungi (Uredinales, Basidiomycetes) are one of the most diverse and economically important plant-obligated parasites. Taxonomy of this group has been under revision during the last years using molecular techniques to define phylogenetic relationships. In this study we evaluated the phylogenetic affinities of a group of 40 rust fungi obtained from different plants in the Colombian Andean region using sequence analysis of the 28S ribosomal DNA, specifically D1/D2 domains. Comparisons were undertaken with sequences of rust fungi from around the world deposited in the GenBank database. An alignment of sequences was used to build a phylogenetic tree through Maximum parsimony analysis. Our results support the taxonomical validity of families Pucciniaceae, Phakopsoraceae, Phragmidiaceae, Pileolariaceae, Mikronegeriaceae, Coleosporiaceae and Cronartiaceae, while Pucciniosiraceae represents redundant taxa with Pucciniaceae. The analyses indicated that Uropyxidaceae, Raveneliaceae, Chaconiaceae and Pucciniastraceae correspond to poly-phyletic families. Melampsoraceae appear to be a basal taxon to the Uredinales. Information obtained in this study will be useful to incorporate a higher number of sequences from tropical rust fungi within global efforts to redefine the taxonomy of order Uredinales. Additionally, we propose to give priority to future phylogenetic studies of taxa: Gerwasia, Hemileia, Phragmidium, Prospodium, Puccinia and Uromyces, genera that include a high number of rust fungi from the tropics. Rev. Biol. Trop. 59 (2): 517-540. Epub 2011 June 01.

Los hongos roya (Uredinales, Basidiomycetes) representan uno de los grupos de fitoparásitos más diversos y con mayor importancia económica agrícola mundial. Su taxonomía se ha basado en el estudio de caracteres morfológicos, que resulta en muchos casos en la formación de taxones polifiléticos. Sin embargo, en los últimos años se han tratado de incorporar herramientas moleculares que conduzcan a la generación de sistemas de clasificación basados en afinidades evolutivas. Este trabajo pretendió aumentar la base del conocimiento sobre la uredobiota tropical, mediante el estudio de características morfológicas y filogenéticas de un grupo de royas de los Andes de Colombia. Para esto se secuenció parte de la región 28S del ADNr y se realizó un análisis de agrupamiento mediante Máxima parsimonia. Los resultados confirmaron la validez de las familias Pucciniaceae, Phakopsoraceae, Phragmidiaceae, Pileolariaceae, Mikronegeriaceae, Coleosporiaceae y Cronartiaceae, mientras que Pucciniosiraceae es un taxón redundante con Pucciniaceae. Por su parte, Uropyxidaceae, Raveneliaceae, Chaconiaceae y Pucciniastraceae se muestran como familias polifiléticas. Aparentemente Melampsoraceae se presenta como un taxón basal al grupo. La información que se deriva de este estudio se espera sea incorporada en los estudios mundiales que buscan redefinir el sistema taxonómico de los hongos roya.

Isolation and fusion of protoplasts from the phytopathogenic fungus Sclerotium rolfsii (Sacc. )

Sclerotium rolfsii (Sacc.) is a serious plant pathogenic fungus and lacks perfect (basidial) stage in production. Protoplast fusion technology was employed to reconstruct fusants from this fungus. Two strains designated as A and R were used. Maximum protoplast yields of 3.8x10(5) /g mycelia and 2.8x10(5) /g mycelia were formed in strains A and R respectively. Osmotic stabilizer sucrose 1M gave maximum yield. Lysing enzyme at the rate of 15mg/ml was found best for yield. Fusion of protoplasts from strains A and R was carried out in fusion media containing PEG 4000 30 percent (w/v) with 0.2mM CaCl2. Four fusants F1, F2, F3 and F4 were recovered. Morphological, physiological and pathogenic characters of fusants were compared with parent strains on carrots, beans and tomato.

Agaricales Fungi from atlantic rain forest fragments in Minas Gerais, Brazil

Two Atlantic Rain Forest fragments in Minas Gerais state were studied to access their Agaricales fungal richness. A total of 187 specimens were collected and 109 species, 39 genera, and eight families were identified. Thirty-three species were cited for the first time in Brazil.

Genomic organization of the structural genes controlling the astaxanthin biosynthesis pathway of Xanthophyllomyces dendrorhous

The cloning and nucleotide sequence of the genes (idi, crtE, crtYB, crtl and crtS) controlling the astaxanthin biosynthesis pathway of the wild-type ATCC 24230 strain of Xanthophyllomyces dendrorhous in their genomic and cDNA version were obtained. The idi, crtE, crtYB, crtl and crtS genes were cloned, as fragments of 10.9, 11.5, 15.8, 5.9 and 4 kb respectively. The nucleotide sequence data analysis indicates that the idi, crtE, crtYB, crtl and crtS genes have 4, 8,4, 11, and 17 introns and 5, 9, 5, 12 and 18 exons respectively. In addition, a highly efficient site-directed mutagenesis system was developed by transformation by integration, followed by mitotic recombination (the double recombinant method). Heterozygote idi (idi+ / idi-::hph), crtE (crtE+ / crtE -::hph), crtYB (crtYB + / crtYB -::hph), crtI (crtI+ / crtI-::hph) and crtS (crtS +/crtS -::hph) and homozygote mutants crtYB (crtYB -::hph/crtYB -::hph), crtI (crtI -::hph/crtI -::hph) and crtS (crtS -::hph / crtS -::hph) were constructed. All the heterozygote mutants have a pale phenotype and produce less carotenoids than the wild-type strain. The genetic analysis of the crtYB, crtl and crtS loci in the wild-type, heterozygote, and homozygote give evidence of the diploid constitution of ATCC 24230 strains. In addition, the cloning of a truncated form of the crtYB that lacks 153 amino acids of the N-terminal region derived from alternatively spliced mRNA was obtained. Their heterologous expression in Escherichia coli carrying the carotenogenic cluster of Erwinia uredovora result in trans-complementation and give evidence of its functionality in this bacterium, maintaining its phytoene synthase activity but not the lycopene cyclase activity.

Expression of the carotenoid biosynthesis genes in Xanthophyllomyces dendrorhous

In the yeast Xanthophyllomyces dendrorhous the genes idi, crtE, crtYB, crtl and ast are involved in the biosynthesis of astaxanthin from isopentenyl pyrophosphate. The carotenoid production and the kinetics of mRNA expression of structural genes controlling the carotenogenesis in a wild-type ATCC 24230 and in carotenoid overproducer deregulated atxS2 strains were studied. The biosynthesis of carotenoid was induced at the late exponential growth phase in both strains. However, the cellular carotenoid concentration was four times higher in atxS2 than in the wild-type strain in the exponential growth phase, suggesting that carotenogenesis was deregulated in atxS2 at the beginning of growth. In addition, the maximum expression of the carotenogenesis genes at the mRNA level was observed during the induction period of carotenoid biosynthesis in the wild-type strain. The mRNA level of the crtYB, crtl, ast genes and to a lesser extent the idi gene, decayed at the end of the exponential growth phase. The mRNA levels of the crtE gene remained high along the whole growth curve of the yeast. In the atxS2 strain the mRNA levels of crtE gene were about two times higher than the wild-type strain in the early phase of the growth cycle.

A new approach for enhanced multiplication of arbuscular mycorrhizal fungi and isolation of ITS regions from Glomus deserticola and Laccaria fraterna.

Rootlets induced from the petiole base of L. purpureus, using IAA and kinetin was used for enhanced multiplication of arbuscular mycorrhizal (AM) fungus, G. deserticula. Using conserved short arbitrary oligonucleotides, as specific primers, we amplified the ITS-region, a molecular marker for fungal identification, from the genomic DNA extracted from cultured spores of G. deserticola, and genomic DNA extracted from the mycelium of L. fraterna. The capacity of fungal colonization and subsequent spore formation of G. deserticola, compared with the natural root system was evaluated. This technology would provide a simple way to multiply AM fungi and to produce spores without microbial contamination useful for further molecular characterization.

T-DNA transfer from Agrobacterium tumefaciens to the ectomycorrhizal fungus Pisolithus microcarpus / Transferencia de T-DNA de Agrobacterium tumefaciens al hongo ectomicorrícico Pisolithus microcarpus

The model ectomycorrhizal fungus Pisolithus microcarpus isolate 441 was transformed by using Agrobacterium tumefaciens LBA1100 and AGL-1. The selection marker was the Shble gene of Streptoallotecius hidustanus, conferring resistance to phleomycin, under the control of the gpd gene promoter and terminator of Schizophyllum commune. Transformation resulted in phleomycin resistant clones which were confirmed by PCR to contain the resistance cassette. A. tumefaciens-mediated gene transfer would allow the development of RNA interference technology in P. microcarpus.

El hongo ectomicorrícico modelo Pisolithus microcarpus aislamiento 441 fue transformado utilizando Agrobacterium tumefaciens LBA 1100 y AGL-1. El marcador de selección fue el gen Shble de Streptoallotecius hidustanus, el cual confiere resistencia a fleomicina, bajo el control del promotor y terminador del gen gpd de Schizophyllum commune. La transformación resultó en clones resistentes a fleomicina comprobándose por PCR la presencia del transgen. La transferencia génica mediada por Agrobacterium podría permitir el desarrollo de la tecnología de interferencia por ARN en P. microcarpus.