Characterization of osmotolerant rhizobacteria for plant growth promoting activities in vitro and during plant-microbe association under osmotic stress

Osmotic stress has a detrimental effect on growth and plant growth promoting activities (PGP) of rhizobacteria. Thus, before exploring the potential of a rhizobacterium as bioinoculant for drought prone areas, it is essential to understand the effect of osmotic stress on their PGP traits. Here, we characterized two osmotolerant bacteria Bacillus sp. and Bacillus cereus for their PGP activities with Brassica sp. under osmotic stress conditions. Osmotic stress did not appear to have any deleterious effect on their growth. Lower level of osmotic stress (20% PEG 6000) in fact improved their growth. Both the rhizobacterial strains possessed multiple PGP activities. Lower level of osmotic stress had beneficial effect on most of the PGP activities, while higher level of osmotic stress (40% PEG 6000) had a detrimental effect on ACC deaminase activity and GA production. Variable effect of osmotic stress on the different PGP activities of the osmotolerant rhizobacteria during plant-microbe association was observed. Lower level of osmotic stress enhanced IAA and exopolysaccharide production while GA production was reduced. Further increase in osmotic stress had a detrimental effect on IAA production, while exopolysaccharide production was enhanced. However, ethylene production by the inoculated plants was reduced under stressed conditions. Inoculation with the osmotolerant rhizobacterial strains enhanced seed germination and seedling fresh weight in mustard under osmotic stress conditions. Thus, these osmotolerant Bacillus sp. and Bacillus cereus strains have potential as bioinoculants for mitigation of water deficit stress in plants in drought affected regions.

Bilateral fusion of primary mandibular lateral incisors and canines: A report of a rare case / Fusão bilateral de dentes decíduos incisivo e canino inferior: relato de um caso raro

Purpose: Synodontia or fusion is a developmental anomaly of shape of tooth formed by union of two independently developing primary or secondary teeth. Prevalence of tooth fusion is estimated at 0.5-2.5% in the primary dentition and less in permanent dentition. The bilateral type of fusion in the primary dentition is rare and is about 0.02%. This paper describes a rare case of bilateral fusion of primary mandibular lateral and canine teeth. Case description: An 8 year old girl had a complaint of unusually large sized teeth in her mandible. After physical examination and use of periapical radiographs and study models bilateral fused teeth in the mandibular lateral incisor and canine region was diagnosed. Conclusion: The bilateral fusion of primary mandibular lateral and canine teeth is a rare condition and should be carefully evaluated to diagnose any associated pathology.

Objetivo: Sinodontia ou fusão é uma anomalia de desenvolvimento da forma do dente formado pela união de dois dentes decíduos ou permanentes em desenvolvimento de forma independente. A prevalência de fusão dental é estimada em 0,5 a 2,5% na dentadura decídua e menor na permanente. O tipo de fusão bilateral na dentadura decídua é rara e aproximadamente de 0,02%. Este artigo descreve um caso raro de fusão bilateral de dentes decíduos incisivos laterais e caninos inferiores. Descrição do caso: Uma menina de 8 anos de idade tinha uma queixa clínica de dentes de tamanho grande anormal em sua mandíbula. Após exame físico e uso de radiografias periapicais e modelo de estudo, a fusão bilateral de dentes decíduos incisivos laterais e caninos inferiores foi diagnosticada. Conclusão: A fusão bilateral de dentes decíduos incisivos laterais e caninos na mandíbula é uma condição rara e deve ser cuidadosamente avaliada para diagnosticar quaisquer patologias associadas.