LR1

The primary aim of this study was to assess if the probiotic Lactobacillus reuteri could be effective in the treatment of gingivitis and further to evaluate the influence of the probiotic on plaque and the lactobacilli population in the saliva. A randomised, placebo-controlled, double blind study was performed over 2 weeks. Fifty-nine patients with moderate to severe gingivitis were included and given one of two different Lactobacillus reuteri formulations (LR-1 or LR-2) at a dose of 2 x 10(8) CFU per day, or a corresponding placebo. At baseline (day 0) gingival index and plaque index were measured on two surfaces and saliva for lactobacilli determination was collected. The patients were instructed how to brush and floss efficiently and study treatment was started.The patients returned on day 14 for final assessment of gingivitis and plaque and saliva was collected. 20 patients were randomised to LR-1, 21 to LR-2 and 18 to placebo. Gingival index fell significantly in all 3 groups (p < 0.0001). LR-1, but not LR-2 improved more than placebo (p < 0.0001). Plaque index fell significantly in LR-1 (p < 0.05) and in LR-2 (p < 0.01) between day o and day 14 but there was no significant change in the placebo group. At day 14, 65% of the patients in LR-1 were colonised with Lactobacillus reuteri and 95% in the LR-2 group. Lactobacillus reuteri was efficacious in reducing both gingivitis and plaque in patients with moderate to severe gingivitis.

There are seven pathotypes of soybean mosaic virus (SMV) representing seven strain groups (G1-G7) in the United States. Soybean genotypes [Glycine max (L.) Merr.] may exhibit resistant (R), susceptible (S), or necrotic (N) reactions upon interacting with different SMV strains. This research was conducted to investigate whether reactions to two SMV strains are controlled by the same gene or by separate genes. Two SMV-resistant soybean lines, LR1 and LR2, were crossed with the susceptible cultivar Lee 68. LR1 contains a resistance gene Rsv1-s and is resistant to strains G1-G4 and G7. LR2 contains the Rsv4 gene and is resistant to strains G1-G7. Two hundred F(2:3) lines from LR1 x Lee 68 and 262 F(2:3) lines from LR2 x Lee 68 were screened for SMV reaction. Seeds from each F2 plant were randomly divided into two subsamples. A minimum of 20 seeds from each subsample were planted in the greenhouse and plants were inoculated with either G1 or G7. G1 is the least virulent, whereas G7 is the most virulent strain of SMV. The results showed that all the F(2:3) lines from both crosses exhibited the same reaction to G1 and G7. No recombinants were found in all the progenies for reactions to G1 and G7 in either cross. The results indicate that reactions to both G1 and G7 are controlled by either the same gene or very closely linked genes. This research finding is valuable for studying the resistance mechanism and interactions of soybean genotypes and SMV strains and for breeding SMV resistance to multiple strains.