Identification and expression analysis of Fragaria vesca MLO genes involved in interaction with powdery mildew (Podosphaera aphanis)

Strawberry powdery mildew, caused by Podosphaera aphanis is a major fungal disease that affects strawberry yield and quality. In the model plant species Arabidopsis and the crop plants barley, tomato and pea, the Mildew resistance locus O (MLO) proteins have been found to be required for powdery mildew susceptibility. The present study, based on the sequence of a wild plum (Prunus americana) MLO protein, identified 16 MLO genes within the genome of woodland strawberry, Fragaria vesca and examined their expression pattern in response to powdery mildew infection in three diploid strawberry cultivars. Phylogenetic analysis showed that the FvMLO genes can be classified into six clades. Four FvMLO genes were grouped into clade III, which comprises MLO genes from Arabidopsis, tomato and grapevine that mediate powdery mildew susceptibility. A RNA-seq analysis of two diploid strawberry cultivars, F. vesca ssp. vesca accession Hawaii 4 (HW) and F. vesca f. semperflorens line “Yellow Wonder 5AF7” (YW) at 1 d (1 DAI) and 8 d (8 DAI) after infection showed the expression of 12 out of the 16 FvMLO genes. The comparison of Fragments Per Kilobase of transcript per Million mapped reads (FPKM values) detected by RNA-seq and expression values of qRT-PCR for FvMLO genes showed substantial agreement. The FvMLO3 gene, which was grouped in clade III and orthologous to the Arabidopsis, tomato and grapevine genes, was highly expressed in YW compared to other FvMLO genes across varieties. The results showed that FvMLO genes can be used as potential candidates to engineer powdery mildew resistance in strawberry based on MLO suppression or genome editing

Global transcriptome analysis and identification of differentially expressed genes after infection of Fragaria vesca with powdery mildew (Podosphaera aphanis)

Background: Podosphaera aphanis, the causal agent of strawberry powdery mildew causes significant economic loss worldwide. Methods: We used the diploid strawberry species Fragaria vesca as a model to study plant pathogen interactions. RNA-seq was employed to generate a transcriptome dataset from two accessions, F. vesca ssp. vesca Hawaii 4 (HW) and F. vesca f. semperflorens Yellow Wonder 5AF7 (YW) at 1 d (1 DAI) and 8 d (8 DAI) after infection. Results: Of the total reads identified about 999 million (92%) mapped to the F. vesca genome. These transcripts were derived from a total of 23,470 and 23,464 genes in HW and YW, respectively from the three time points (control, 1 and 8 DAI). Analysis identified 1,567, 1,846 and 1,145 up-regulated genes between control and 1 DAI, control and 8 DAI, and 1 and 8 DAI, respectively in HW. Similarly, 1,336, 1,619 and 968 genes were up-regulated in YW. Also 646, 1,098 and 624 down-regulated genes were identified in HW, while 571, 754 and 627 genes were down-regulated in YW between all three time points, respectively. Conclusion: Investigation of differentially expressed genes (log2 fold changes �5) between control and 1 DAI in both HW and YW identified a large number of genes related to secondary metabolism, signal transduction; transcriptional regulation and disease resistance were highly expressed. These included flavonoid 3´-monooxygenase, peroxidase 15, glucan endo-1,3-β-glucosidase 2, receptor-like kinases, transcription factors, germin-like proteins, F-box proteins, NB-ARC and NBS-LRR proteins. This is the first application of RNA-seq to any pathogen interaction in strawberr

Mass transfer coefficient evaluation for lab scale fermenter using sodium sulphite oxidation method

Oxygen transfer is often the rate-limiting step in the aerobic bioprocess due to the low solubility of oxygen inside the aqueous solution. The rate of reaction is such that as oxygen enters the liquid phase, it is immediately consumed to oxidize the sulfite so that the rate of oxidation is equivalent to the oxygen-transfer rate.  Reaction rate often determined by titration is much faster than oxygen transfer rate so that gas- liquid mass transfer is the rate controlling step. The current study involves using central composite design, a statistical technique to find out the parameter conditions for the optimum volumetric mass transfer coefficient in a lab scale (2L) fermentor. The optimum volumetric mass transfer coefficient was found to lie outside the range of parameters studied and analytical expressions was obtained to predict the volumetric mass transfer coefficients for the parameter ranges studied using response surface methodology.  The analytical expression was found to be significantly valid based on ANOVA results. Keywords: Aerobic bioprocess; Sodium sulphite oxidation process; Mass transfer coefficient; Central composite desig

Economic valuation of marine ecosystem services: Methodological issues and challenges

The economy has a complex relationship with the environment. The environment not only provides the raw materials and energy for the production of goods and services that support people’s lifestyles, but also sustains damage through the activities of households and businesses. Environmental economics, being a sub-field of economics, is concerned with environmental issues. According to the quoting from the National Bureau of Economic Research Environmental Economics program, “Environmental Economics undertakes theoretical or empirical studies of the economic effects of national or local environmental policies around the world. Particular issues include the costs and benefits of alternative environmental policies to deal with air pollution, water quality, toxic substances, solid waste, and global warming’’. Environmental economics seeks to assess various losses due to the economic activities and to fix upon the most competent way to reduce them, as well as to compare the cost of environmental damage to the cost of mitigation

4-{[(E)-(3-Phenyl-1H-pyrazol-4-yl)methyl­idene]amino}-1H-1,2,4-triazole-5(4H)-thione

In the title compound, C12H10N6S, a weak intra­molecular C—H⋯S hydrogen bond stabilizes the mol­ecular conformation. The pyrazole and triazole rings form a dihedral angle of 17.82 (8)°. The mol­ecule adopts an E configuration with respect to the central C=N double bond. In the crystal, inter­molecular N—H⋯N and N—H⋯S hydrogen bonds link mol­ecules into chains propagating in [20]