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The prized Red banana, selected for superior qualities, demands strong genetic uniformity for successful clonal propagation and preservation. Ensuring this uniformity early in the growth of in vitro Red banana plants is essential, as gene mutations and chromosome rearrangements during tissue culture can jeopardize both cloning and germplasm conservation. In this situation, molecular markers play a pivotal role in confirming genetic stability. Thus the study aims to discover a marker that identifies tissue-cultured Red bananas from their virescent variants during initial sub-culturing. A marker linked to anthocyanin has been identified which effectively differentiated Red bananas from virescent variants and it was further validated in various banana cultivars, ornamental Musa species and their interspecific hybrids. The PCR-based marker showed remarkable specificity, discerning Red bananas from virescent variants during tissue culture. It also distinguished green and red offspring, cutting time and resource costs, and shortening the banana breeding cycle. [ABSTRACT FROM AUTHOR]

Magnaporthe oryzae is one of the most devastating pathogenic fungi that affects a wide range of cereal plants, especially rice. Rice blast disease causes substantial economic losses around the globe. The M. oryzae genome was first sequenced at the beginning of this century and was recently updated with improved annotation and completeness. In this review, key molecular findings on the fungal development and pathogenicity mechanisms of M. oryzae are summarized, focusing on fully characterized genes based on mutant analysis. These include genes involved in the various biological processes of this pathogen, such as vegetative growth, conidia development, appressoria formation and penetration, and pathogenicity. In addition, our syntheses also highlight gaps in our current understanding of M. oryzae development and virulence. We hope this review will serve to improve a comprehensive understanding of M. oryzae and assist disease control strategy designs in the future. [ABSTRACT FROM AUTHOR]

Despite popular usage of medicinal plants, their effects as cardiovascular protective agents have not been totally elucidated. We hypothesized that treatment with aqueous extract from Prosopis strombulifera (AEPs) and Tessaria absinthioides (AETa), Argentinian native plants, produces antioxidant effects on vascular smooth muscle cells (VSMCs) and attenuates atherogenesis on apolipoprotein E-knockout (ApoE-KO) mice. In VSMCs, both extracts (5–40 μg/ml) inhibited 10% fetal calf serum-induced cell proliferation, arrested cell in G2/M phase, reduced angiotensin II-induced reactive oxygen species (ROS) generation, and decreased NADPH oxidase subunit expression. In ApoE-KO mice, extracts significantly reduced triglycerides and lipid peroxidation [plasma thiobarbituric acid reactive substances (TBARS)], increased plasma total antioxidant status (TAS), and improved glutathione peroxidase activity in the liver. Under high-fat diet (HFD), both extracts were able to inhibit O2– generation in the aortic tissue and caused a significant regression of atheroma plaques (21.4 ± 1.6% HFD group vs. 10.2 ± 1.2%∗ AEPs group and 14.3 ± 1.0%∗ AETa group; ∗ p < 0.01). Consumption of AEPs and AETa produces antioxidant/antimitogenic/anti-atherosclerotic effects, and their use may be beneficial as a complementary strategy regarding cardiovascular disease therapies. Schematic representation of the effect of P. strombulifera or T. absinthioide decoctions on VSMC and ApoE-KO mice. The combination of antimitogenic effect and antioxidant capacity of the extracts is effective to increase antioxidant status and reduce atheroma development modulating NADPH oxidase expression. [ABSTRACT FROM AUTHOR]

Disease spread of Pseudocercospora fijiensis, causal agent of the black Sigatoka disease of banana, depends on ascospores produced through the sexual reproductive cycle. We used phylogenetic analysis to identify P. fijiensis homologs (PKS8-4 and Hybrid8-3) to the PKS4 polyketide synthases (PKS) from Neurospora crassa and Sordaria macrospora involved in sexual reproduction. These sequences also formed a clade with lovastatin, compactin, and betaenone-producing PKS sequences. Transcriptome analysis showed that both the P. fijiensis Hybrid8-3 and PKS8-4 genes have higher expression in infected leaf tissue compared to in culture. Domain analysis showed that PKS8-4 is more similar than Hybrid8-3 to PKS4. pPKS8-4:GFP transcriptional fusion transformants showed expression of GFP in flask-shaped structures in mycelial cultures as well as in crosses between compatible and incompatible mating types. Confocal microscopy confirmed expression in spermagonia in leaf substomatal cavities, consistent with a role in sexual reproduction. A disruption mutant of pks8-4 retained normal pathogenicity on banana, and no differences were observed in growth, conidial production, and spermagonia production. GC-MS profiling of the mutant and wild type did not identify differences in polyketide metabolites, but did identify changes in saturated fatty acid methyl esters and alkene and alkane derivatives. To our knowledge, this is the first report of a polyketide synthase pathway associated with spermagonia. [ABSTRACT FROM AUTHOR]

The fungal high osmolarity glycerol (HOG) pathway is composed of a two-component system (TCS) and Hog1-type mitogen-activated protein kinase (MAPK) cascade. A group III (Nik1-type) histidine kinase plays a major role in the HOG pathway of several filamentous fungi. In this study, we characterized a group III histidine kinase, NikA/TcsC, in the life-threatening pathogenic fungus, Aspergillus fumigatus. A deletion mutant of nikA showed low conidia production, abnormal hyphae, marked sensitivity to high osmolarity stresses, and resistance to cell wall perturbing reagents such as congo red and calcofluor white, as well as to fungicides such as fludioxonil, iprodione, and pyrrolnitrin. None of these phenotypes were observed in mutants of the SskA response regulator and SakA MAPK, which were thought to be downstream components of NikA. In contrast, in response to fludioxonil treatment, NikA was implicated in the phosphorylation of SakA MAPK and the transcriptional upregulation of catA, dprA, and dprB, which are regulated under the control of SakA. We then tested the idea that not only NikA, but also the other 13 histidine kinases play certain roles in the regulation of the HOG pathway. Interestingly, the expression of fos1, phkA, phkB, fhk5, and fhk6 increased by osmotic shock or fludioxonil treatment in a SakA-dependent manner. However, deletion mutants of the histidine kinases showed no significant defects in growth under the tested conditions. Collectively, although the signal transduction network related to NikA seems complicated, NikA plays a crucial role in several aspects of A. fumigatus physiology and, to a certain extent, modulates the HOG pathway. [ABSTRACT FROM AUTHOR]

The hemibiotrophic fungus Mycosphaerella fijiensis is the causal agent of black Sigatoka (BS), the most devastating foliar disease in banana (Musa spp.) worldwide. Little is known about genes that are important during M. fijiensis-Musa sp. interaction. The fungal cell wall is an attractive area of study because it is essential for maintenance of cellular homeostasis and it is the most external structure in the fungal cell and therefore mediates the interaction of the pathogen with the host. In this manuscript we describe the in silico identification of glycosyl phosphatidylinositol-protein (GPI) family in M. fijiensis, and the analysis of two β-1,3-glucanosyltrans-ferases (Gas), selected by homology with fungal pathogenicity factors. Potential roles in pathogenesis were evaluated through analyzing expression during different stages of black Sigatoka disease, comparing expression data with BS symptoms and fungal biomass inside leaves. Real-time quantitative RT-PCR showed nearly constant expression of MfGAS1 with slightly increases (about threefold) in conidia and at speck-necrotrophic stage during banana-pathogen interaction. Conversely, MfGAS2 expression was increased during biotrophy (about seven times) and reached a maximum at speck (about 23 times) followed by a progressive decrease in next stages, suggesting an active role in M. fijiensis pathogenesis. [ABSTRACT FROM AUTHOR]

In the current study, the antioxidant and anti-inflammatory potential of hydroethanolic extract of T. foenum-graecum seeds was evaluated. Phenolic profiling of T. foenum-graecum was conducted through high-performance liquid chromatography-photodiode array (HPLC-PDA) as well as through the mass spectrometry technique to characterize compounds responsible for bioactivity, which confirmed almost 18 compounds, 13 of which were quantified through a chromatographic assay. In vitro antioxidant analysis of the extract exhibited substantial antioxidant activities with the lowest IC50 value of both DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) inhibition assays. The extract was found to be non-toxic against human RBCs and murine macrophage RAW 264.7 cells. Moreover, the extract significantly (p < 0.001) reduced the lipopolysaccharide (LPS)-induced tumor necrosis factor alpha (TNF-α), intrlukin-6 (IL-6), prostaglandin E2 (PGE2), and nitric oxide (NO) in RAW 264.7 cells in a concentration-dependent manner. The hydroethanolic extract of T. foenum-graecum exhibited considerable anti-inflammatory potential by decreasing the cellular infiltration to the inflammatory site in both carrageenan-induced peritonitis and an air pouch model of inflammation. Pretreatment with T. foenum-graecum extract caused significant improvement in antioxidants such as superoxide dismutase (SOD), CAT (catalase), malondialdehyde (MDA), and myeloperoxidase (MPO) against oxidative stress induced by carrageenan. Based on our results of in vivo and in vitro experimentation, we concluded that hydroethanolic extract of T. foenum-graecum is a potential source of phenolic compounds with antioxidant and anti-inflammatory potential. [ABSTRACT FROM AUTHOR]

Zingiber zerumbet (L) Smith, a wild clonal species related to the cultivated ginger ( Zingiber officinale Roscoe), is a potential resistance donor for soft rot disease in ginger caused by Pythium aphanidermatum (Edson) Fitzp. In this study we evaluated the genetic diversity and P. aphanidermatum resistance of 74 Z. zerumbet accessions belonging to 15 populations from eight districts in Kerala state, India. The disease index (DI) of the accessions varied from 0% to 72.24% and the accessions could be separated into six frequency classes according to their DI values. More than 65% of the accessions had a DI < 20%. Eight accessions were found to be immune to the infection. The relative frequency of resistant accessions was higher in the central and northern regions of Kerala. Amplified fragment length polymorphism (AFLP) analysis of Z. zerumbet accessions using five primer combinations yielded 215 bands in total, of which 175 (81.4%) were polymorphic. Nei’s genetic diversity (h) of 0.2738 and Shannon information index (I) of 0.4012 revealed a high genetic diversity in Z. zerumbet unexpected for a clonal species. In the UPGMA dendrogram, accessions were clustered mostly according to their geographical origin and no clear correspondence was observed between the clustering pattern of accessions and their responses to Pythium aphanidermatum. The study revealed high genetic diversity and variability for pathogen resistance among Z. zerumbet accessions and confirmed the value of Z. zerumbet as a potential donor for soft rot resistance for the genetic improvement of ginger. [ABSTRACT FROM AUTHOR]

The extracts of two mangrove species, Bruguiera cylindrica and Laguncularia racemosa, have been analyzed at sub-lethal concentrations for their potential to modulate biofilm cycles (i.e., adhesion, maturation, and detachment) on a bacterium, yeast, and filamentous fungus. Methanolic leaf extracts were also characterized, and MS/MS analysis has been used to identify the major compounds. In this study, we showed the following. (i) Adhesion was reduced up to 85.4% in all the models except for E. coli, where adhesion was promoted up to 5.10-fold. (ii) Both the sum and ratio of extracellular polysaccharides and proteins in mature biofilm were increased up to 2.5-fold and 2.6-fold in comparison to the negative control, respectively. Additionally, a shift toward a major production of exopolysaccharides was found coupled with a major production of both intracellular and extracellular reactive oxygen species. (iii) Lastly, detachment was generally promoted. In general, the L. racemosa extract had a higher bioactivity at lower concentrations than the B. cylindrica extract. Overall, our data showed a reduction in cells/conidia adhesion under B. cylindrica and L. racemosa exposure, followed by an increase of exopolysaccharides during biofilm maturation and a variable effect on biofilm dispersal. In conclusion, extracts either inhibited or enhanced biofilm development, and this effect depended on both the microbial taxon and biofilm formation step. [ABSTRACT FROM AUTHOR]