Salinity reduces fertility in rice {Oryza sativa L.), but littie is known of the underlying cause(s). In order to determine the relative irmportance of pollen viability and stigmatic receptivity for seed setting, plants of the rice cultivar IR36 were treated with 'artificial' sea water (0,10, 25 or 50mol m with respect to NaCl) from 1 month after germination until the main tiller flowered.An increase in the salinity in the medium resulted in a decrease in the number of fertile fiorets and in the viability ot pollen as determined both hy pollen germination and hy pollen staining with the tetrazolium salt 3-(4,5-dimethylithyazolyl),.2,5-diphenyl monotetrazolium hromide.In order to assess the effects of salt on stigmas, seed production was measured for salt-grown and non-salt-grown female plants pollinated with viahle pollen (from plants grown in the ahsence of salt). The percentage of seed set was reduced hy 38% when the female plants were grown in 10 mol m~^ Na and hy 72% at 25 mol m~' Na: no seed setting was recorded for plants grown in 50 mol m""^ Na. Comparisons between crosses involving male and female parents grown at different salinities indicated that etfects on the female plants dominated those on pollinator plants.Mineral analysis of leaves of different ages showed that there was a gradient of K concentration from leaf to leaf which was opposite to that of Na and CI at all levels of applied salinity: K was maximal in the flag leaf, where Na and CI were minimal. Analysis also revealed that there was an increase in the concentrations of Na and CI and a decrease in the concentration of K in the pollen grains and stigmas of plants subjected to saline conditions. Correlations between the concentration of Na knd CI in pollen and pollen staining and pollen germination in vitro suggest that Na and C\perse were responsible for the poor viability. The change in ionic concentrations in pollen and stigmas was much larger than that in the younger leaves, and in particular very much larger than that in the lemmas and paleas.

No abstract

The effect of salinity on the reproductive physiology of five rice genotypes (IR54, IR26, IR2153-26-3-5-2, IR 15324-117-3-2-2 and BR6), was investigated by treatment from panicle initiation with sodium concentrations of 20, 35 or 50 mol m -3 in an 'artificial seawater'. In an experiment conducted in a glasshouse, plant height and dry weight were little affected by the treatments. There was, however, genotypic variation in the extent of the sodium accumulation, with IR15324-117-3-2-2 containing the highest and IR2153-26-3-5-2 the lowest concentrations: sodium concentrations were higher in older than younger leaves.Salinity delayed flowering, reduced the number of productive tillers, the number of fertile florets per panicle, the weight per grain and the grain yield: effects on grain yield were very much more severe than on vegetative growth. Panicle length was also reduced as was the number of primary branches in a panicle: again there was genotypic variation in the response of these characters to salinity, with the number of branches in IR2153-26-3-5-2 being particularly sensitive.The concentration of sodium increased in the pollen, stigmas, lemmas and paleas with each increment of external salinity. The highest concentrations of sodium in pollen and stigmas was recorded in IR54 and IR15324-117-3-2-2. Pollen viability, whether tested with the tetrazolium salt thiazolyl blue (3-{4,5-dimethylthiazolyl-2}-2,5-diphenyl monotetrazolium bromide or MTT), germination on stigmas, growth through the stylar tissue or F1 seed set, was reduced particularly in those genotypes accumulating most sodium. At all three salt levels, a genotype which accumulated more Na in its pollen produced less-viable pollen than those with less Na in their pollen. Since the amount of Na in the pollen was highly correlated with the Na in the flag leaf, assessment of flag leaf Na should prove a useful indicator of the likely pollen viability. Stigmatic receptivity was also reduced, when estimated either from germination of viable pollen on stigmas of salt-grown plants, its growth through the stylar tissue or Fl seed set. The reduction of seed set in crosses suggested that the overall consequences of salinity are dominated by effects on panicle development, stigmas and grain filling rather than on pollen.Analysis of the data suggests that genotypic variation exists in the extent to which salinity affects aspects of the plants reproductive physiology and development: this variation might be used in attempts to enhance the resistance of rice to salinity.

Eleven dead or sick birds submitted from farms in the year 2010 with a history of sudden death with respiratory and/or diarrhoeal signs were used for isolation and identification of Newcastle disease virus (NDV). All samples were subjected to routine necropsy. Pooled respiratory tissues were inoculated in embryonated chicken eggs and chicken embryo fibroblast (CEF) cell culture. The growth of NDV was confirmed by embryo mortality, cytopathic effects (CPE) in cell culture, haemagglutination (HA) and haemagglutination inhibition (HI) test. The presence of NDV was confirmed by reverse transcriptionpolymerase chain reaction (RT-PCR). At necropsy seven cases were tentatively diagnosed as Newcastle disease (ND). Out of seven ND-suspected samples, four yielded virus in both embryos and cell culture, while one was positive only in embryos, one only in cell culture and one sample was negative in both embryos and cell culture. RT-PCR successfully amplified a 766 bp fragment covering parts of Matrix and Fusion protein genes of NDV from the samples that were positive either in embryos or in cell culture. It is suggested that RT-PCR could be a rapid and sensitive tool for the detection of NDV.

West Nile Virus (WNV) is a life threatening flavivirus that causes significant morbidity and mortality worldwide. No preventive therapeutics including vaccines against WNV are available for human use. In this study, immunoinformatics approach was performed to design a multi epitope-based subunit vaccine against this deadly pathogen. Human (HLA) and Mice (H-2) allele specific potential T-cell and B-cell epitopes were shortlisted through a stringent procedure. Molecular docking showed selected epitopes that have stronger binding affinity with human TLR-4. Molecular dynamics simulation confirmed the stable nature of the docked complex. Furthermore, in silico cloning analysis ensures efficient expression of desired gene in the microbial system. Interestingly, previous studies showed that two of our selected epitopes have strong immune response against WNV. Therefore, selected epitopes could be strong vaccine candidates to prevent WNV infections in human. However, further in vitro and in vivo investigations could be strengthening the validation of the vaccine candidate against WNV.