Classical taxonomic studies of the bamboos are based on floral morphology and growth habit, which can cause problems in identification due to erratic flowering. Identification and genetic relationships in 12 species of bamboo were investigated using random amplified polymorphic DNAs (RAPD) technique. Analysis started by using thirty 10-mer primers that allowed us to distinguish 12 species and to select a reduced set of primers. The selected primers were used for identification and for establishing a profiling system to estimate genetic diversity. A total of one hundred thirty seven distinct polymorphic DNA fragments (bands), ranging from 0.4-3.3 kb were amplified by using 10 selected primers. The genetic similar analysis was conducted based on presence or absence of bands, which revealed a wide range of variability among the species. Cluster analysis clearly showed two major clusters belonging to 12 species of bamboo. Two major clusters were further divided into three minor clusters. The species of Bambusa vulgaris and Bambusa vulgaris var. striata were the most closely related and formed the first minor cluster along with Bambusa ventricosa. The variety of Bambusa multiplex var. Silver stripe and Bambusa multiplex were very closely related and there was no variation with Bambusa ventricosa. Another minor cluster was obtained between Bambusa arundinacea, Cephalostachyum pergracil and Bambusa balcooa. The RAPD technique has the potential for use in species identification and genetic relationships between taxa and species of bamboo for breeding program.

Isolation and characterization of microsatellites was analysed in Bambusa arundinacea and cross species amplification studied in other bamboos. Microsatellites, tandem repeats of short nucleotide (1-6 bp) sequences, are the DNA marker of choice because of their highly polymorphic, ubiquitous distribution within the genome, ease of genotyping through Polymerase chain reaction, selectively neutral, codominant and multiallelic nature. Six microsatellites, three polymorphic and three monomorphic have been characterized for the first time in a bamboo species, Bambusa arundinacea belonging to the family Poaceae. The numbers of alleles per locus ranged from 2 to 13. Cross species amplification was tested in 18 other bamboo species. Monomorphic simple sequence repeats (SSRs) were found to be cross amplified in most of the species tested and polymorphic ones in only three to four species. The utility of SSR loci in a genetic diversity study of B. arundinacea and other cross-amplified bamboo species has been discussed. This study will help in population genetic studies in bamboo species.

Alpha amylases have various applications in food processing industries, for example, baking, brewing and distillery industries. Studies of the Ca 2+ independent α-amylase production were carried out by a strain of Bacillus brevis MTCC 7521 isolated from a brick kiln soil. The optimum temperature, pH and incubation period for amylase production were 50°C, 6.0 and 36 h, respectively. The enzyme secretion was at par in the presence of any of the carbon sources (soluble starch, cassava starch and cassava flour). B. brevis produced more amylase in presence of beef extract as nitrogen source in comparison to other organic nitrogen sources (peptone, yeast extract and casein) and asparagine, potassium nitrate, ammonium sulphate, ammonium nitrate and urea reduced the enzyme activity. The addition of Ca 2+ (10-40 mM) or surfactants (Tween 20, Tween 40, Tween 60, Tween 80, and sodium lauryl sulphate at 0.02% concentration) in culture medium did not result in further improvement in the enzyme production. The purified enzyme had a molecular mass of 205 kDa in native SDS-PAGE.

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Fusarium species mainly produce fumonisins group of mycotoxins which are classified as Group 2B human carcinogen by International Agency for Research on Cancer (IARC). In poor storage conditions, Fusarium species producing fumonisins can infect rice or paddy (Oryza sativa L.) which is the highest produced and consumed staple food in India. A rapid molecular method using primer Fum5F and Fum6R detected 85% fumonisin producers among 28 Fusarium isolates from Indian rice cultivars. Genetic variability of the isolates was studied by PCR based RAPD assay using 13 random primers. A total of 169 polymorphic bands were obtained by 13 markers with an average polymorphism information content (PIC) of 0.665 and overall polymorphism of 88%. Primer 3B showed a polymorphism of 96% with PIC value of 0.66 and it amplified 26 scorable fragments hence may be useful for the analysis of genetic variation among Fusarium isolates. Four strains (F47, F90, F92 and F96) in which fum gene wasn't amplified by Fum5F and Fum6R and supposed to be non producer of fumonisin have been consistently placed in one separate group by RAPD primers. Genetic variation of toxic Fusarium in rice from India is less studied. RAPD proved to be a suitable tool for depicting Polymorphism among the isolates. The high genetic variability among the Fusarium isolates used in the current study is a matter of concern considering the importance of Rice in India. Highlights• Fumonisins are Group 2B human carcinogen produced by Fusarium species.• Fum5F and Fum6R primer pair detected fumonisin producers.• RAPD primers deciphered 88% polymorphism among 26 Fusarium isolates.

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Rice blast is a devastating disease which is caused by the heterothallic fungus Magnaporthe oryzae. Compatible sexual recombination which occurs between two M. oryzae strains of different mating types, can enhance genetic variability. Assessment of mating type alleles is used as a marker to measure population diversity. Forty six isolates of M. oryzae were collected from infected rice leaves from various ecosystems of coastal Odisha, India, and the mating type analysis using molecular markers was carried out. MAT1-1 mating type was dominating in all the ecosystems and MAT1-2 was found to be present in uplands as well as in irrigated fields. Both mating types could be found in the same field in irrigated ecosystem. The disease spread was very fast vertically as well as horizontally in those fields resulting in blast lesions looking as 'green islands (gi) produced in senescence leaves', and MAT1-2 was found to be associated with all gi lesions. Consequently, the management of the disease in those plots was very difficult. Interestingly, ribosomal RNA IGS region could not be amplified in MAT1-2 isolates but consistent amplification was obtained in MAT1-1 mating type isolates.