BackgroundMacrophomina phaseolina is one of the most destructive necrotrophic fungal pathogens that infect more than 500 plant species throughout the world. It can grow rapidly in infected plants and subsequently produces a large amount of sclerotia that plugs the vessels, resulting in wilting of the plant.ResultsWe sequenced and assembled ~49 Mb into 15 super-scaffolds covering 92.83% of the M. phaseolina genome. We predict 14,249 open reading frames (ORFs) of which 9,934 are validated by the transcriptome. This phytopathogen has an abundance of secreted oxidases, peroxidases, and hydrolytic enzymes for degrading cell wall polysaccharides and lignocelluloses to penetrate into the host tissue. To overcome the host plant defense response, M. phaseolina encodes a significant number of P450s, MFS type membrane transporters, glycosidases, transposases, and secondary metabolites in comparison to all sequenced ascomycete species. A strikingly distinct set of carbohydrate esterases (CE) are present in M. phaseolina, with the CE9 and CE10 families remarkably higher than any other fungi. The phenotypic microarray data indicates that M. phaseolina can adapt to a wide range of osmotic and pH environments. As a broad host range pathogen, M. phaseolina possesses a large number of pathogen-host interaction genes including those for adhesion, signal transduction, cell wall breakdown, purine biosynthesis, and potent mycotoxin patulin.ConclusionsThe M. phaseolina genome provides a framework of the infection process at the cytological and molecular level which uses a diverse arsenal of enzymatic and toxin tools to destroy the host plants. Further understanding of the M. phaseolina genome-based plant-pathogen interactions will be instrumental in designing rational strategies for disease control, essential to ensuring global agricultural crop production and security.

Jute (Corchorus sp.) is one of the most important sources of natural fibre, covering ∼80% of global bast fibre production1. Only Corchorus olitorius and Corchorus capsularis are commercially cultivated, though there are more than 100 Corchorus species2 in the Malvaceae family. Here we describe high-quality draft genomes of these two species and their comparisons at the functional genomics level to support tailor-designed breeding. The assemblies cover 91.6% and 82.2% of the estimated genome sizes for C. olitorius and C. capsularis, respectively. In total, 37,031 C. olitorius and 30,096 C. capsularis genes are identified, and most of the genes are validated by cDNA and RNA-seq data. Analyses of clustered gene families and gene collinearity show that jute underwent shared whole-genome duplication ∼18.66 million years (Myr) ago prior to speciation. RNA expression analysis from isolated fibre cells reveals the key regulatory and structural genes involved in fibre formation. This work expands our understanding of the molecular basis of fibre formation laying the foundation for the genetic improvement of jute.

Jute fibre is the second most important fibre next to cotton. It is obtained from the bark of plant through microbial retting process. Here we report optimized microbial retting protocol that can lower retting period and produce high fibre quality. A total of 451 bacterial colonies have been isolated from five jute retting water samples in Bangladesh. Higher pectinolytic bacterial isolates were predominant in the later stage of jute retting. Out of these, 168 isolates have been screened by both semi-quantitative and quantitative pectinase, xylanase and cellulase enzyme assay. Among them, 144 isolates have been selected on the basis of extra cellular enzyme activity of these three enzymes. 16 s ribosomal gene sequencing analysis identified 2 phyla-Firmicutis (80.55%) and Proteobacteria (19.45%). To check the synergistic and antagonistic effect 10 selected isolates were tested in 167 different combinations. Three best combinations were identified that lowered retting period from 18-21 days to 10 days producing high quality fibre in both laboratory and field trial. This improved retting technology can be adopted in industrial scale for the production of quality jute fibre in a controlled condition in reduced water quantity without polluting the environment.Jute, second most important natural fibre after cotton, is cultivated in East Asia and some parts of Latin America 1-3 . Jute is a bast or phloem fibre in the bark of stems, cemented together by pectin and gummy substances 4 . Commercial extraction of jute fibre is water based microbiological retting where jute bundles are submerged into slow running river water and subjected to decomposition of pectin, hemicelluloses, and other mucilaginous substances 2,5 . In this process, pectin is depolymerized by pectinases, primarily comprising four enzymes: Polygalacturonase (PG), Pectin Lyase (PNL), Pectate lyase and Pectin esterase. However, PG 6 , and PNL 7 are primary retting enzymes. In addition, xylanase makes jute fibre softer by selective removal of non-fibrous hemicelluloses without affecting strength of cellulosic fibre. Pectinolytic microorganisms having xylanase activity devoid of cellulase activity is an additional beneficial aspect to improve fibre quality 8 . The quality of fibre is largely determined by the efficiency of retting process 1,2,9,10 and various factors are responsible for proper retting as well as improved fibre quality. Most promising water based microbiological retting process mostly involves bacteria along with various fungi, protozoa, algae and diatoms 10-13 . Main aerobic retting bacteria belong to genus Bacillus viz., B. subtilis, B. polymyxa, B. mesentericus, B.pumilus, B. cereus, B. megaterium and B. macerans, initiate retting 14-18 along with large numbers of gram-negative genera such as Erwinia and Pseudomonas 9,19 . At the later stage of retting some anaerobic bacteria from genus Clostridium -Clostridium acetobutylicum, Clostridium stercorarium, Clostridium tertium come to carry on the retting process 20 . As microorganisms are the ma...

The enzymatic activity of Thermomyces lanuginosus BPJ-10 and Rhizomucor pusillus BPJ-2 were observed through qualitative screening programme which was demonstrated by the hydrolysis of substrate on solid media. Both the fungi exhibited potential xylanolytic and pectinolytic activities whereas no cellulase activity was observed in T. lanuginosus BPJ-10 and very low cellulase activity was found in R. pusillus BPJ- 2. The optimum temperature for mycelial growth of T. lanuginosus BPJ-10 and R. pusillus BPJ-2 were found to be 50 and 45°C, respectively, whereas the optimum pH for both of them were 6.5 and 5, respectively. Out of five culture media used, both the fungi showed maximum radial mycelia growth on Potato Dextrose Agar. DOI: http://dx.doi.org/10.3329/bjb.v42i2.18021 Bangladesh J. Bot. 42(2): 207-213, 2013 (December