Salinity screening of 24 rice genotypes was performed at the reproductive stage for evaluating their salt tolerance level. On the basis of yield and yield components, genotypes were categorized as tolerant, susceptible and moderately tolerant. PBRC-30, Ashfal, Horkuch, STL-20 and Pokkali were found as tolerant while Binadhan-7, S-39 L-11, S-37 L-27, S-37 L-36 and S-37 L-39 were found as susceptible. Selected three SSR markers viz. RM336, RM21 and RM510 were used to determine salinity tolerance. The genetic diversity was ranges from 0.8194 to 0.8854 with an average of 0.8530. The highest PCI value was 0.8742 and the lowest was 0.8004 from RM510 and RM21, respectively. The UPGMA clustering system generated six genetic clusters. The highest genetically dissimilarity of (Cluster 1) vs (Cluster 2 sub-cluster A) and the crossing would be helpful for salt tolerant rice development. Thus, selected SSR primers and genotypes would be useful in marker assisted breeding, quantitative trait loci (QTL) mapping and gene pyramiding in breeding programmed for improvement of rice for salt tolerance.

Three long and 1 short reversed-phase C18 columns were compared for separation of deoxynivalenol (DON) in extracts of naturally contaminated wheat samples using liquid chromatography with ultraviolet detection and liquid chromatography/mass spectrometry (LC/MS). Among the 3 long columns used, a Symmetry C18 column with an isocratic solvent mixture of wateracetonitrilemethanol (90 + 5 + 5, v/v/v) gave the best separation for DON without interferences from other compounds in the wheat extracts. The Symmetry short (75 mm) column was comparable with the long column (250 mm) in resolving DON but significantly reduced retention time (i.e., 5.8 versus 16.3 min). Increasing the column temperature from 25 to 45C resulted in a further reduction in retention time. Identity of DON in the wheat extracts and standard solutions was confirmed by LC/MS in the positive ion mode, whereby DON appeared with an (M+1)+ ion at a mass-to-charge ratio of 297 plus fragment ions associated with loss of water and/or a 30 atomic mass unit (amu) CH2O fragment. The Symmetry short column was also capable of separating a mixture of the mycotoxins DON, 15-acetyl-DON, nivalenol, and zearalenone by use of a combination of an isocratic and gradient solvent system. The overall method showed high precision, exhibiting a relative standard deviation of 4.8%, limit of detection of 50 ng/g, and limit of quantitation of 165 ng/g. It was significantly correlated with enzyme-linked immunosorbent assay analysis, indicating its appropriateness for safety and quality assurance of wheat and related grains.

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Embryogenic calli from mature seeds of four indica rice genotypes were used to observe their regeneration potentiality and establish a suitable in vitro plantlet regeneration protocol. MS medium supplemented with different phytohormone combinations were used to observe the callus induction ability of the explant. The highest callus induction (73.19%), biggest size of callus (3.133mm) and higher callus weight (0.7167g) were observed in Binadhan-6 in MS medium supplemented with 1.0 mg L-1 2,4-D over all the genotypes and MS medium supplemented with 1.5 mg L-1 2,4-D was the best over all the treatments (66.83%). Among the phytohormone combinations, MS + 8 mg L-1 Kinetin + 0.5 mg L-1 NAA showed the highest shoot regeneration (50.67%) and shoot length (13.7cm). Among the genotypes, Binadhan-6 was highly responsive to shoot regeneration (55.83%). The best root formation from regenerants (87.889%), maximum number of roots per plant (20) and the highest length (4.467 cm) of roots were in MS media supplemented with 0.5 mg L-1 IAA in Binadhan-6. In pot and soil, Binadhan-6 showed the highest survival rate of the plantlet 91.30% and 85%, respectively. This callus induction and in vitro regeneration protocol will be widely applicable for the tissue culture of indica rice.