Adaptation à la pénétration racinaire de deux Ustilaginaceae parasites du mais : Ustilago maydis et Sporisorium reilianum - Analyse microscopique et transcriptomique

Les Ustilaginaceae constituent une famille de champignons basidiomycètes responsables de maladies du charbon chez les Poaceae. L'aptitude à l'infection racinaire du maïs par Ustilago maydis a été comparée à celle de Sporisorium reilianum, champignon du sol pénétrant au niveau des racines. Les analyses en microscopie et en diagnostic moléculaire ont permis de montrer qu'U. maydis présente la même capacité que S. reilianum à pénétrer les racines de maïs, mais aussi de plantes non hôtes. Cette infection n'entraîne toutefois aucun symptôme dans nos conditions d'essai. L'aptitude à la pénétration racinaire a été corrélée à la propension de trois espèces d'Ustilaginaceae (Moesziomyces penicillariae, U. maydis, S. reilianum) à former des souches solopathogènes infectieuses. Il apparaît que l'espèce strictement aérienne M. penicillariae a une plus forte propension à générer des souches solopathogènes que les espèces telluriques. Nous interprétons ce résultat comme une adaptation à la dissémination aérienne sur longue distance. Nous montrons également qu'U. maydis et S. reilianum perçoivent les strigolactones, molécules exsudées par les racines des plantes. L'ajout de GR24, un analogue de synthèse de strigolactone, induit chez ces deux espèces une augmentation de leur respiration cellulaire, et une induction précoce de gènes impliqués dans la respiration cellulaire. Ce résultat jette de nouvelles perspectives sur le rôle des strigolactones dans la constitution de la rhizosphère.Ustilaginaceae are a family of basidiomycetes fungi causing smut disease on Poaceae. The ability of Ustilago maydis and Sporisorium reilianum, a maize root infecting species, to penetrate maize roots was compared. Root infection was investigated by using different microscopic techniques and PCR detection. We observed that U. maydis have similar behavior than S. reilianum on maize root, but also on non host plant. Maize root infection by U. maydis didn't lead to symptom apparition in our experimental conditions. We correlated the root infecting ability of three Ustilaginaceae species (Moesziomyces penicillariae, U. maydis, S. reilianum) to their propensity to generate solopathogenic infectious strains. The strict aerial species M. penicillariae generates far more solopathogenic cells than the telluric species. It could then be proposed that solopathogeny is an adaptative mechanism to aerial dispersal on long distance. We showed that U. maydis and S. reilianum could perceive root exuded molecules, strigolactones. The addition of GR24, a synthetic analog of strigolactone, induced on these species a previous induction of genes involved in cell respiration and an increase of the cell respiration. These results give a new insight on the role of the strigolactones in the rhizosphere

Antibacterial activity of Marrubium vulgare L. against antibiotic resistance Klebsiella pneumoniae strains

Background and aims: Herbal medicines are the major remedy in traditional medical systems and have a great contribution in maintaining human health and preventing many infectious diseases. The aim of this study was to assay antibacterial potential of Marrubium vulgare L. extract against Klebsiella pneumoniae resistant strains to current antibiotics and also GC/MS analysis to better understanding the extract composition. Methods: In this experimental research, 30 K. pneumoniae strains isolated from urine culture of hospitalized patients were used. The essential oil of Marrubium vulgare L. was obtained by hydro distillation for 2 hours using the Celevenger with yield of 75. Methanolic extract from M. vulgare L. was prepared using Rotary apparatus. In order to determine chemical composition of essential oil, gas chromatography coupled with mass spectrometry (GC-MS) was performed. The minimum inhibitory concentrations and minimum bacterial concentrations were investigated to characterize the antimicrobial activities of this essential oil and its extract. Data were analyzed using analysis of variance (one-way) to determine the statistical differences between different tests. Results: The results showed that K. pneumoniae strains were resistant to 4 or 3 agents including: Ampicillin (65), Gentamicin (30), Sulfamethoxazol (25). The lowest and the highest MIC value of M. vulgare L. extract were 2.5 and 10 mg/mL, respectively. The highest and the lowest MIC value of M. vulgare L. essential oil was 5 and 1/25 mg/m respectively. Conclusion: The present study confirmed that essential oil and extract of this plant could be served as an antibacterial agent in pharmaceutical industry

Global, regional, and national cancer incidence, mortality, years of life lost, years lived with disability, and disability-Adjusted life-years for 29 cancer groups, 1990 to 2017 : A systematic analysis for the global burden of disease study

Importance: Cancer and other noncommunicable diseases (NCDs) are now widely recognized as a threat to global development. The latest United Nations high-level meeting on NCDs reaffirmed this observation and also highlighted the slow progress in meeting the 2011 Political Declaration on the Prevention and Control of Noncommunicable Diseases and the third Sustainable Development Goal. Lack of situational analyses, priority setting, and budgeting have been identified as major obstacles in achieving these goals. All of these have in common that they require information on the local cancer epidemiology. The Global Burden of Disease (GBD) study is uniquely poised to provide these crucial data. Objective: To describe cancer burden for 29 cancer groups in 195 countries from 1990 through 2017 to provide data needed for cancer control planning. Evidence Review: We used the GBD study estimation methods to describe cancer incidence, mortality, years lived with disability, years of life lost, and disability-Adjusted life-years (DALYs). Results are presented at the national level as well as by Socio-demographic Index (SDI), a composite indicator of income, educational attainment, and total fertility rate. We also analyzed the influence of the epidemiological vs the demographic transition on cancer incidence. Findings: In 2017, there were 24.5 million incident cancer cases worldwide (16.8 million without nonmelanoma skin cancer [NMSC]) and 9.6 million cancer deaths. The majority of cancer DALYs came from years of life lost (97%), and only 3% came from years lived with disability. The odds of developing cancer were the lowest in the low SDI quintile (1 in 7) and the highest in the high SDI quintile (1 in 2) for both sexes. In 2017, the most common incident cancers in men were NMSC (4.3 million incident cases); tracheal, bronchus, and lung (TBL) cancer (1.5 million incident cases); and prostate cancer (1.3 million incident cases). The most common causes of cancer deaths and DALYs for men were TBL cancer (1.3 million deaths and 28.4 million DALYs), liver cancer (572000 deaths and 15.2 million DALYs), and stomach cancer (542000 deaths and 12.2 million DALYs). For women in 2017, the most common incident cancers were NMSC (3.3 million incident cases), breast cancer (1.9 million incident cases), and colorectal cancer (819000 incident cases). The leading causes of cancer deaths and DALYs for women were breast cancer (601000 deaths and 17.4 million DALYs), TBL cancer (596000 deaths and 12.6 million DALYs), and colorectal cancer (414000 deaths and 8.3 million DALYs). Conclusions and Relevance: The national epidemiological profiles of cancer burden in the GBD study show large heterogeneities, which are a reflection of different exposures to risk factors, economic settings, lifestyles, and access to care and screening. The GBD study can be used by policy makers and other stakeholders to develop and improve national and local cancer control in order to achieve the global targets and improve equity in cancer care. © 2019 American Medical Association. All rights reserved.Peer reviewe

Adaptation à la pénétration racinaire de deux Ustilaginaceae parasites du mais (ustilago maydis et Sporisorium reilianum)

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Original Article. Identification of Cercospora species in southwestern Iran

Cercospora species are associated with leaf spot symptoms on various host plants. In this research, nine species of the genus on some medicinal and economic crops were found in diff erent locations in Kohgiluyeh and Boyerahmad Provinces (southwestern Iran) and examined according to morphological characteristics of stromata, conidiophores, conidiogenous cells and conidia. Results showed that Cercospora species on Cichorium intybus (C. cichorii) and Nasturtium offi cinale (C. nasturtii) are new for the mycobiota of Iran. However, characteristics of Cercospora on Plantago lanceolata are very similar to the description of C. plantaginis, but morphologically indistinguishable from C. apii s. lat. Other species have already been reported from other parts of Iran, but are new in southwestern Iran. Furthermore, Rumex crispus and Trifolium resupinatum are new hosts for C. apii and C. zebrina in Iran, respectively

Identification of Cercospora species in southwestern Iran

Cercospora species are associated with leaf spot symptoms on various host plants. In this research, nine species of the genus on some medicinal and economic crops were found in different locations in Kohgiluyeh and Boyerahmad Provinces (southwestern Iran) and examined according to morphological characteristics of stromata, conidiophores, conidiogenous cells and conidia. Results showed that Cercospora species on Cichorium intybus (C. cichorii) and Nasturtium officinale (C. nasturtii) are new for the mycobiota of Iran. However, characteristics of Cercospora on Plantago lanceolata are very similar to the description of C. plantaginis, but morphologically indistinguishable from C. apii s. lat. Other species have already been reported from other parts of Iran, but are new in southwestern Iran. Furthermore, Rumex crispus and Trifolium resupinatum are new hosts for C. apii and C. zebrina in Iran, respectively

Jasmonic Acid Induced Systemic Resistance in Infected Cucumber by Pythium aphanidermatum

Damping-off disease of cucumber is one of the most destructive diseases of cucumber in worldwide. In this work, the potential of jasmonic acid (JA) for induce resistant against damping off disease was investigated. The effect of JA on activity of Polyphenol oxidase (PPO), Peroxidase (PO) and Catalase (CAT) enzymes and total phenol was assayed by spectrophotometric method. Expression level of three plant defense genes as Lipoxygenase, Cupi4 and Phenylalanine ammonia-lyase genes was analyzed using qRT-PCR method. Drop-plate method was used to assay inhibitory effect of JA on radial growth of fungi. Exogenic application of JA decreased disease severity in the infected plants but did not inhibit mycelia growth on solid medium compared to control. Our results showed that JA application substantially increased the activity of oxidative enzymes at different concentration. The highest enzyme activity was recorded after 48 hours post infection (hpi) at a concentration of 400 mg L-1 of JA. Gene expression analysis revealed that JA is differentially able to increase the mRNA transcripts of all tested genes at 48 hpi. The expression level of Cupi4 gene was higher than the other genes in treated plants. Induced systemic resistance by JA was mediated through an enhanced expression of ISR marker genes and increase of antioxidant enzymes activity. Based on these results, we suggest that exogenic application of JA could be considered as plant resistance inducer.&nbsp

The Effect of Chitosan on the Induction Systemic Resistance against Pythium aphanidermatum in Cucumber

Introduction: Land use change, deforestation, grazing, intentional and unintentional fire and invasive pests and diseases are all the major cause of damage to the Zagros forest ecosystem. The green oak leaf roller (Tortrix viridana L.) is one of the important pests of Zagros forests. Larvae of the pest significantly damage the oak forests with feeding on leaves and buds of different species of oaks each year. Larvae enter 2'd instar after eating the internal contents of oak buds, then the third and 4th instars larvae consume whole buds and even oak leaves. After development to the 5th larval instar, they roll the leaves and enter the pupal stage. The attacked trees revitalize by creating new leaves from early May onwards. New leaves, pale green and are smaller than normal leaves. Continuation of the pest activity on Quercus species causes gradual weakness the trees and readiness to accept a variety of secondary pests and diseases in later years. Based on the status of Zagros forests and their importance in the conservation of soil and water sources, the nutritional indices of Tortrix viridana larvae of two species of Oak i.e. Quercus infectoria and Q. libani were determined to get a better understanding of this pest. Materials and Methods: Since early April, with regular visits, last instar larvae (5th instar) of T. viridana in oak forests in Perdanan areas (around the village Ghabr Hossein) were collected and transferred to the laboratory chamber. The larvae were fed on the two oak species. The leaves of these species were collected and transported to the laboratory in a room at a temperature of 25°C and suitable photoperiod conditions. The larvae were fed individually or in a group. In a grouping method, 10 larvae in two replicates and in individually method 40 larvae (one larva per replicate) for each host were considered. Larval weight, amount of consumed food and weight of feces were estimated by using a sensitive digital Carriage scale (0.001 gr). Relative consumption rate (RCR), relative growth rate (RGR), the efficiency of conversion of ingested food (ECI), the efficiency of conversion of digested food (ECD) and approximate digestibility (AD) were also calculated. For statistical analysis t-test and SPSS17 software were used to compare the mean of the data. Results and Discussion: Results of t-test (α=5%) indicated that the larval biomass, RGR, ECI, and AD were significantly different among the hosts in both methods of grouping and individually rearing of the larvae. In this study, Q. libani showed the lowest rate of digestibility. The larvae fed on Q. infectoria have the higher rate of AD than Q. libani because of high RCR, RGR, ECD and ECI. Also, the results related to the comparison of two methods (grouping and individually rearing of the larvae), on nutritional indices were significantly different and in both host trees, the rate of RGR, ECI and ECD in grouping method was more than individually rearing method. RCR is the indication of the insect's exploitation speed of food. In the other words, it shows feeding rate regarding insect's weight at the specific point of time depending on the amount of water and other nutrition physicochemical characteristics in insects. The result showed that this index rate in group rearing method on two host species is equal, but in individual rearing method on Q. infectoria, it is more than Q. libani. The possible reasons are more feeding of larvae in individual rearing method due to the lack of competition stress, the more likelihood of the desirability of Q. infectoria compared to Q. libani, the probability of the existence of antixenosis in Q. libani. The similar study investigating individual and group rearing methods in one insect species is not available. This result confirms that T. viridana larvae’s has a tendency toward social life and in the group situation, they eat effectively. In fact, although larvae in individual form feed more because of lack of competition stress, but in the group they make use of that little food in the best way. Conclusion: In this study, Q. libani had low food quality. As a result, its relative consumption rate, relative growth rate, the efficiency of conversion of ingested food and efficiency of conversion of digested food was less than Q. infectoria. According to the results, Q. infectoria is an appropriate host for this pest. Also, it shows that the larvae were more considering the rate of larval biomass, RCR, RGR, ECI and ECD in grouping method than the single method