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Root cap cuticles (RCCs), comprising mainly very-long-chain fatty acids (VLCFAs), promote salt tolerance by preventing ion influx. Glycosylphosphatidylinositol-anchored lipid transfer protein (LTPG)1 and LTPG2 participate in VLCFA deposition in the extracellular region, aiding RCC formation in the lateral roots. In this study, we investigated whether LTPG1 and LTPG2 have similar functions in the primary roots of young Arabidopsis thaliana. Phenotypic analyses, fluorescence microscopy, and quantitative real-time reverse transcription polymerase chain reaction confirmed that NaCl exposure induced LTPG1 and LTPG2 expression and promoted RCC formation in young primary roots. The loss of RCC in the ltpg1 and ltpg2 mutants resulted in increased NaCl sensitivity of root elongation. NaCl also upregulated the expression of several NaCl-responsive genes in ltpg1 and ltpg2. We conclude that RCC formation via LTPG function is pivotal in enhancing salt tolerance in young primary roots. [ABSTRACT FROM AUTHOR]

Copyright of Listy Cukrovarnicke a Reparske is the property of VUC Praha a.s. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To evaluate the prevalence of pulp stones in a Turkish paediatric cohort from the Isparta district using panoramic radiographs. Methods: Panoramic radiographs of 19,857 children and adolescents between the ages of 9 and 18 years were retrospectively analysed to determine the prevalence and distribution of pulp stones. Teeth with pulp stones were classified in terms of dentition, location, dental status and complete or incomplete root formation. Statistical analysis was carried out by applying Chi‑square and Mann–Whitney U. Univariate logistic regression analysis was applied to determine the factors affecting pulp stone status. Differences were considered as significant when p < 0.05. Results: Out of a total of 19,857 patients, pulp stones were identified in 6.5%. Among the 548,415 teeth examined, 0.96% had pulp stones. The incidence of pulp stones in girls (7.4%) was higher than in boys (5.7%) (p < 0.001). The prevalence of pulp stones increased with age and was significantly higher in molar teeth. A significant difference existed in the incidence of pulp stones according to the jaws (p < 0.001). In both jaws, no statistically significant difference was observed in terms of teeth with pulp stones being on the right and left (p = 0.834). Of molars with pulp stones, 91.8% had completed root formation. The majority of patients (37.7%) had pulp stones in four teeth. Conclusion: Knowing the incidence of pulp stones in paediatric patients by dentists, endodontists, and paediatric dentists will help prevent complications that may occur during applications by facilitating the determination of appropriate methods, especially during endodontic procedures. [ABSTRACT FROM AUTHOR]

Copyright of China Journal of Oral & Maxillofacial Surgery is the property of Shanghai Jiao Tong University, College of Stomatology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of RGO: Revista Gaúcha de Odontologia is the property of RGO: Revista Gaucha de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the relationship between chronological age and third molar root development for a Peruvian population. In this retrospective analytical study, the sample comprised 1367 panoramic radiographs from people of known chronological age and sex. The root development was classified through Demirjian's stages. Intra-observer agreement was determined using Kappa statistics. Simple and multiple linear regression was used to predict the chronological age from the root development of the third molars. Symmetry in root development of right and left third molars within the same jaw was 78.54% (Kappa: 0.72; p0.05). However, there was only 57.94% concordance between the maxillary and mandibular third molars (Kappa: 0.47). Root formation was completed earlier in males than in females, in stages F, G and H. The probability that a person was at least 18 years old was high when their third molars were completely formed (stage H), and there was an increased probability that subjects with root development between stages A and E were underage. These empirical probabilities and regression formulas can be provided for forensic and médicolegal purposes. The mean difference between chronological and dental age was about 1.50 years when any molar was used, this difference decreased to 1.39 years when four molars were assessed. Third molars root development occurred earlier in the Peruvian population than in the German, Japanese, South African and mixed American populations, but later than the Spanish population; it was similar to the Canadian, US Hispanic, and French-Canadian populations. [ABSTRACT FROM AUTHOR]

To investigate the molecular mechanism of the ADVENTITIOUS ROOTING RELATED OXYGENASE 1 (ARRO-1) gene in adventitious rooting of tree peony, the PsARRO-1 gene was isolated from Paeonia ostii. Subsequently, a yeast two-hybrid (Y2H) cDNA library using the split-ubiquitin yeast membrane system was constructed, the insert fragments lengths of pPR3-N membrane Y2H library were mainly concentrated between 500 and 3,000 bp, and the library capacity reached 1.3 × 107 CFUs, with an efficiency of recombinant of 100%, which met the requirements for subsequent screening of PsARRO-1-interacting proteins. Finally, 15 candidate PsARRO-1-interacting proteins were screened out by pBT3SUC-ARRO, among them potassium transporter 2, cytochrome b5 isoform E, and high mobility group B protein 3 (HMGB3) might be involved in the formation of roots. Both direct Y2H and bimolecular fluorescence complementation assays confirmed that PsARRO-1 interacted with PsHMGB3, which shared high identity with EgHMGB3 and MiHMGB3. The expression of PsHMGB3 was significantly up-regulated in the root outgrowth stage, and the overexpression of PsHMGB3 in Arabidopsis resulted in lengthened primary roots, more lateral roots. In short, the Y2H library provides a large number of useful resources for functional genomics research on roots of tree peony. [ABSTRACT FROM AUTHOR]

Background: Dimocarpus longan is a tropical tree that produces edible fruit. It is a neglected plant species that is listed as near threatened. In spite of its economic value, the propagation of longan cultivar using conventional methods is extremely difficult. The goal of this research is to produce and conserve this plant through in vitro propagation. Results: In order to form new shoots, sterilized shoot tip explants were cultured on Murashige and Skoog (MS) medium supplemented with benzyl adenine (BA) or 2-isobentenyl-adenine (2ip). For direct organogenesis, young leaves of new shoots were cultured on MS medium fortified with various concentrations of Thidiazuron (TDZ) or 6-(4-Hydroxy-3-methylbut-2-enylamino purine) (Zeatin). Gibbrellic acid (GA3) at different levels alone or in combination was used for shoot elongation. Also, indole-3-butyric acid (IBA) and naphthalene acetic acid (NAA) were used for root formation. MS medium supplemented with 1.00 mg/l 2ip was suitable for inducing axillary shoots from shoot tips (4.0 axillary shoots/explant). The highest significant 76% and numbers of adventitious buds from leaf base were achieved on MS medium containing 1.0 mg/l TDZ. These buds developed into the longest plantlets on GA3 at 3.0 mg/l and rooted well in ½MS containing 1.50 mg/l IBA plus 0.50 mg/l (NAA). About 70% in vitro plants were successfully acclimatized. The AFLP profile illustrated the genetic stability of gene expression action. The amplified fragment length polymorphisms (AFLPs) profile illustrated the progenies were extremely similar to the mother plants. According to our findings, MS medium containing 25 ppm salicylic acid (SA) and 5 ppm methyl jasmonate (MeJA) produced the highest percentage of apigenin in longan calli (77.09 and 2.637%, w/w). Conclusion: A successful and efficient micropropagation protocol has been developed and described here for the first time, and it will be very useful for the clonal propagation and conservation of the near-threatened Dimocarpus longan plant. Micropropagated plants are genetically identical to the donor plant using the AFLP technique. The usefulness of salicylic acid and methyl jasmonate as elicitors for increasing in vitro production of secondary metabolites in plants is demonstrated in this work. [ABSTRACT FROM AUTHOR]

Aim: To describe features of maxillary permanent canines in the late mixed stage as seen in panoramic radiograph (PTG) that later needed treatment to erupt into the oral cavity and to compare them with naturally erupted canines. Methods: The cross-sectional part of this retrospective register-based study consisted of 1454 PTGs of children (mean age 9.3 years) living in Eastern Finland, while the longitudinal part involved patient data on 184 treated maxillary canines. The variables examined were treatment needs, overlapping and inclination of the maxillary canines, the development stage of the canines and lateral incisors and dental age. Results: Only 11.6% of the maxillary canines needed treatment, including interceptive procedures. The treated canines significantly more often had overlapping (p < 0.001), larger inclination (p = 0.001) and incomplete lateral incisors (p = 0.002) than did the naturally erupted canines. The children treated significantly more often had a delayed dental age (p = 0.035). Clear overlapping was closely associated with all treatment modalities, whereas some overlapping and a large inclination angle (≥ 25°) were associated especially in cases of late treatment. An incomplete lateral incisor and delayed dental age were associated with treatment. Conclusion: An association with treatment needs was found especially in the case of overlapping and a large inclination angle of the maxillary canine a couple of years before eruption into the oral cavity. These features can be early signs and indications for instant or later treatment of a maxillary canine and underline the importance of monitoring space conditions and erupting canines. [ABSTRACT FROM AUTHOR]

The present work is a biomarker-based analysis to understand reduction in arsenic toxicity in rice plants due to co-application of iron and silicon. Both iron and silicon have been co-applied in the soil of the potted rice plants with a specific dose of arsenic. The results showed, increase in root arsenic content with only Fe application (E1) as 115% and decrease in shoot arsenic content as 35.4% against control, with Fe + Si application (E2) the root arsenic increased 44% compared to E1 and shoot arsenic content decreased almost 50%, 73% and 25% increase in root Fe content in E1 and E2 is due to formation of Fe-plaque on the root surface which is further justified by the SEM image. The increased arsenic content in the plant root is due to deposition of arsenic in the root Fe-plaque. Plant health parameters revealed that 18% increase in Carbohydrate in E1 compared to control and 9% increase in E2 compared to E1, chlorophyll and protein content followed a similar trend. Malonaldehyde (MDA) content revealed a decrease of 20% in E1 and E2 plants. Super Oxide-dismutase (SOD), an antioxidant enzyme, the unique biomarker to understand the plant stress, showed a decreasing trend of 11% in E1 compared to control and more than 50% in E2 compared to E1, the expression study of the SOD-gene also showed a positive correlation with the biochemical data. [ABSTRACT FROM AUTHOR]

Chinese fir is the most important evergreen coniferous species for afforestation in subtropical China due to rapid growth and excellent timber quality. Plant cutting propagation plays key role in the vegetative propagation, and is more practical for rejuvenation. This study was focused on understanding the influencing mechanism of adventitious root formation, and we investigated rooting capacity of different scion methods in two different cutting orchards. The results showed that TC (the cuttings from the cutting orchard of "burying trunk with crown") has highest rooting capacity, indicating the cutting orchard has better rejuvenation effect. The ascorbate peroxidase (APX activity), Jasmonic acid (JA) and N-((-)-jasmonoyl)-S-isoleucine [JA-Ile] of cutting phloem were correlated to rooting capacity. The genes involved in the plant hormone signal pathway showed different regulation to rejuvenation, differentially expressed genes (DEGs) in indole-3-acetic acid (IAA) and Brassinosteroid (BR)-related pathway were mostly upregulated, while DEGs in abscisic acid (ABA) and gibberellins (GA)-related pathway were mostly downregulated. Phenylpropanoid biosynthesis and terpenoid backbone biosynthesis genes were significantly up-related in roots, the DFR (dihydroflavonol 4-reductase) genes in flavonoid biosynthesis were upregulated in seedlings submitted to treatments with higher degree of rejuvenation with respect to seedlings submitted to lower degree of rejuvenation. Through weighted gene co-expression network analysis (WGCNA) analysis, we identified key genes including SAUR, A-ARR , HDR , HDS and POX. The SEM model indicated different scions directly positively affected rooting, APX activity and HDR gene, and cutting phloem JA negatively affected rooting. These results lay the foundation for further studies on rejuvenation in woody plants, and open new avenues for increasing the efficiency of vegetative propagation of other woody species. • The cuttings from cutting orchard of "burying trunk with crown" showed highest rooting capacity. • Cuttings stem phloem JA and APX activity significantly affected rooting capacity. • DEGs in IAA and BR-related pathways were mostly upregulated, while DEGs in ABA and GA-related pathways were mostly downregulated. • Genes involved in phenylpropanoid biosynthesis and terpenoid backbone biosynthesis were upregulated. [ABSTRACT FROM AUTHOR]

The primary aim was to evaluate the degree of root development of permanent canines at the time of alveolar eruption. We also aimed to assess whether differences in the degree of root development at alveolar eruption exist between permanent canines and premolars and between maxilla and mandible. A cross-sectional study. Barts and The London School of Medicine and Dentistry, Queen Mary University of London. Two hundred dental panoramic radiographs taken as part of routine dental care. Radiographs were assessed for canine and premolar root development stage and eruption level with calibration and repeat measurements undertaken. Two hundred and sixty teeth were identified as being at the level of alveolar eruption. The majority of maxillary canines reached alveolar eruption when root formation was complete. Most premolars and mandibular canines reached alveolar eruption when roots were three-quarters developed. At alveolar eruption, canines were statistically more mature than premolars (p<0.001) and maxillary teeth were more mature than mandibular teeth (p<0.05). Root development appears to be particularly advanced for maxillary permanent canines, being essentially root-complete at alveolar eruption, while premolars and mandibular permanent canines appear to have three-quarters root development at this stage. This information may be used to inform whether and when to extract primary teeth for orthodontic reasons. [ABSTRACT FROM AUTHOR]

Anterior crossbite interferes with appearance, causing a lack of self-confidence, especially for women. Although the prevalence of anterior crossbite is small, the anterior teeth have an important aesthetic role due to being related to smiling, laughing, and speaking. This study aims to review of four cases of anterior crossbite treatment. Clinical related presentation and intervention: an acrylic tool with a posterior bite riser is used to correct the anterior crossbite and align the incisors. Another case of anterior dental crossbite was treated using a composite inclined plane and fixed appliance. The final result of the treatment showed that the occlusion between the maxilla and mandible was quite good, and the anterior crossbite was corrected. What is unique about this case report is that the anterior crossbite differs in its treatment due to the difference in age and the difference in space available in the maxilla. In conclusion, anterior crossbite accompanied by incomplete root formation can be treated using a composite inclined plane. Whereas, complete root formation can be treated using a posterior bite riser or fixed appliance. Proper management of anterior crossbite from both functional and aesthetic perspectives is of utmost importance for the overall success of orthodontic treatment. [ABSTRACT FROM AUTHOR]

Aim: To describe the variation of eruption pattern of maxillary canines in the late mixed stage of dentition seen in PTG when eruption was later natural. Methods: Material for this longitudinal and retrospective register-based study consisted of 1454 PTGs of children living in Eastern Finland (mean age 9.3 years, SD 0.6). Natural eruption of a canine consisted of 744 PTGs (336 girls and 408 boys) including 1488 maxillary canines. The variables examined were treatment/natural eruption, overlapping, inclination, dental age, developmental stage of the canine and lateral incisor. Results: Only 2.0% of maxillary canines had clear overlapping and 56.2% no overlapping was detected at the age of 8.5–10.5 years. Large inclination angle (≥ 25°) was found for 5.5% of examined canines. Overlapping of canine with lateral incisor root decreased as the development of canine root exceeded 1/3. Larger inclinations occurred at earlier stages but decreased significantly as the root developed from 1/3 to 1/2. Mean inclination was significantly larger at children with normal dental age and/or incomplete lateral incisors when overlapping occurred. Regardless overlapping mean inclination was larger if dental age was delayed and/or lateral incisors incomplete. Conclusion: Some overlapping and larger inclination in maxillary canine are features of normal eruption pattern at an earlier stage of canine development and while lateral incisor is incomplete in PTG (8.5–10.5 years). In addition to the overlapping and inclination, stages of canine and lateral incisor root as well as dental age should be observed radiologically when evaluating erupting maxillary canine in children of this age. [ABSTRACT FROM AUTHOR]

As the number of patients with osteoporosis requiring orthodontic treatment is increasing with the aging of society, it is necessary to evaluate the relations between bone metabolism in old age and orthodontic tooth movement (OTM). However, the effects of changes in bone metabolism due to osteoporosis on OTM and root resorption are still unclear. Therefore, we investigated the effects of OTM and root resorption in a mouse ovariectomy (OVX)-induced osteoporosis model. Eight-week-old female wild-type mice underwent OVX or sham surgery (Sham) as controls. One month after treatment, a nickel titanium coil spring was used to apply a mesial force to the maxillary left first molars of OVX or Sham mice for 12 days. The distance between the maxillary first molar and the second molar changed due to OTM and osteoclast formation was evaluated. The odontoclast formation and root resorption along the root surface of the distobuccal root of the first molar was also evaluated by histological analysis and scanning electron microscopy. Distance of tooth movement and osteoclast formation were significantly increased in OVX mice compared to Sham controls. Furthermore, root resorption in the mesial surface of the distal molars induced by orthodontic force was significantly increased in OVX mice. The amount of OTM was significantly increased, and the accompanying root resorption was also increased in OVX mice. Therefore, attention should be paid to the risk of root resorption associated with orthodontic treatment in patients with osteoporosis. [ABSTRACT FROM AUTHOR]

The autotransplantation of a third molar represents an alternative treatment solution for filling an edentulous space that may exist because of traumatic avulsion, agenesis, large carious processes, or other reasons, particularly in young patients. Autotransplantation can offer many benefits, including maintenance of a normally functioning periodontium, preservation of pulp vitality, and completion of root formation. This case report describes a successful autotransplantation of an open-apex maxillary third molar germ to replace a hopeless mandibular first molar in a growing patient. After 24 months of follow-up, the donor tooth showed physiological mobility, absence of infection and ankylosis, positive pulp vitality, and fully formed periodontal integration. Radiographic examination confirmed a remarkable radicular edification. [ABSTRACT FROM AUTHOR]

Aim: The aim of this case series study is to classify deviations in mandibular and maxillary premolar eruption according to aetiology, with a focus on the resorption pattern in the preceding primary molars. The purpose is also to give treatment guidance based on aetiology. Materials and methods: Radiographic material from 64 cases with abnormal premolar eruptions were grouped into three eruptions phases: Phase 1, from tooth bud to early root formation, sub-grouped according to "ankylosis" or "not ankylosis" of the primary molars; Phase 2, from start of eruption to the penetration of gingiva, sub-grouped according to normal or abnormal resorption of the primary molars and Phase 3, eruption after penetration of gingiva. Results: Phase 1: early ankylosis of primary molars, ectopic locations of the premolar crown, including occlusally displacement in relation to the primary molar, are demonstrated. Not ankylosed primary molar: different positions, even an upside-down position of the premolar, are demonstrated. The conditions are explained in relation to the early migration pattern of the premolar tooth bud. Regarding treatment, in cases with ankylosed primary molars these should be extracted as soon as diagnosed and in cases with not ankylosed primary molars these should be extracted when root formation of the premolars has started. The premolars should be observed and saved if possible. Phase 2: non-exfoliation of primary molar, aetiology and treatment of premolars depend on tissue types involved. In bone dysplasia, the eruption of premolars is delayed. In these cases, the primary molars should be extracted when eruptive movements of the premolars have started. In cases with ectoderm deviation, the crown follicle does not function normally during the resorption of the primary molars and the recommended treatment is extraction of primary molars before root closure of premolars. In cases in Phase 2 where the premolars were ankylosed these should be surgical removed. Phase 3: different aetiologies are highlighted, with focus on abnormal innervation and enzyme defects. The premolars are seemingly ankylosed, and surgery might be the only treatment. Conclusion: The case series presented demonstrate how ectopic and arrested premolars have different aetiologies and as a consequence, different treatments. The study highlights several aspects in pathological eruption, which still need to be elucidated. [ABSTRACT FROM AUTHOR]

Ankylosis of a molar during active growth leads to a significant vertical bone defect, extrusion of the opposing molar, and inclination of adjacent teeth. Treatment timing is an essential factor for the patient's quality of life. Early extraction of the ankylosed molar and protraction of the second molar is challenging because of the difficulty of tooth movement and the uncertainty of the normal eruption of the third molar. In view of the uncertainty of eruption of the mandibular third molar, it is essential to assess the potential for eruption according to the developmental stage of the third molar and to secure sufficient space for eruption. In this case report, a girl with an ankylosed right mandibular first molar and an advanced vertical bone defect was treated via early extraction of the ankylosed molar along with the intrusion of the maxillary molar and mesial root movement of the second molar before the initiation of third molar root formation. Restoration of the vertical bone defect was noted at the end of treatment. In addition, spontaneous eruption of the third molar was observed, which was in contrast to the mesioangular impaction of the contralateral third molar. This case emphasizes the importance of treatment timing to increase the chance of utilization of the third molar. [ABSTRACT FROM AUTHOR]

Effects of silver diamine fluoride preparations (SDFs) on cariogenic biofilm formation on root dentin (RD) were investigated. Streptococcus mutans (S. mutans) biofilms were formed on bovine RD blocks coated with one of three the SDFs (38%-SDF, 3.8%-SDF and 35%-SDF+potassium-iodide; SDF+KI) and a non-coated Control which were quantified (spectrometric-measurement) and thickness measured (optical coherence tomography) after 20 h. Bacterial viability test (BacLight) and biofilm-morphometry (SEM) of 2 h biofilms were also performed. The amounts of biofilms (bacteria and water insoluble glucan) and the thickness of biofilm were minimum on 38%-SDF specimen; 3.8%-SDF and SDF+KI had significantly more than that, but had significantly less than Control (p<0.05). Most S. mutans cells found dead and morphology damaged by 38%-SDF. Some dead bacteria and remarkably damaged biofilms were observed in case of 3.8%-SDF and SDF+KI. Inhibition potential of 3.8%-SDF and SDF+KI on S. mutans biofilm formation is almost similar, although not equivalent to 38%-SDF. [ABSTRACT FROM AUTHOR]

Oftentimes, social work education is in denial of its seductive and pervasive relationship with White Supremacy, as if it is exempt in power relations rooted in racial formation. The present paper investigates the historical legacy of racial formation within the United States context and its inception in the field of social work. This paper provides comprehensive definitions of the key terms used in teaching social work practice from an anti-racist social justice lens. Whiteness theory is used to highlight the way social work has perpetuated White Supremacy in the evolution of the profession and Black feminist standpoint is used to examine the experiences of non-White women as they interface with racist and oppressive social systems. I advocate for the use of a social justice pedagogy in social work education to help students think critically and reflectively about their future practice to better understand the oppressive power structures in many of today’s agencies, organizations, and institutions. [ABSTRACT FROM AUTHOR]

Soil cadmium (Cd) causes toxicity and oxidative stress, alters biochemical processes and root knot formation in rice. Irrigation of exogenous peroxidase (POX) together with its co-substrate H 2 O 2 (POX Rice + H 2 O 2), is likely to have protective effect upon the biochemical and nodular changes in rice grown in Cd-rich soil. Exposure to Cd concentration of 1.00 mg/L increased oxidative stress, loss of cell viability, electrolyte leakage and root knot formation, whereas it significantly lowered the chlorophyll level and rhizobium growth in rice. Irrigation of exogenous POX Rice + H 2 O 2 to Cd-stressed rice seedlings reversed the Cd-induced alterations in rice to levels similar in control (non-stressed) seedlings. Results provided strong evidence of exogenous POX Rice + H 2 O 2 -mediated reversal and restoration of physiological and biochemical processes as well as increased resistance of rice seedlings to root knot formation. Irrigation with POX Rice + H 2 O 2 appeared to contribute towards bringing normoxic conditions in the otherwise hypoxic soil environment by enhancing the O 2 in pot-experiments due to reduced Cd uptake, enhanced mineral homeostasis of essential elements viz. P, Fe, Mo, Mg and Mn for maintenance of root architecture damaged by lipid peroxidation and reduction in oxidative stress by reducing Cd-induced reactive oxygen species generation. Therefore, the mitigation of Cd-toxicity in rice through this novel approach appeared to be a promising mode to limit Cd-uptake, modulate protective and tolerance mechanisms for sustainable rice yield in Cd-contaminated rice-croplands and prevent nematode attack in rice, however, more detailed studies are needed prior to large scale applications. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effects of unilateral loss of the lower first permanent molar (L6) on the position and development of the lower third molar (L8). Material and Methods: Fifty-four panoramic radiographs of subjects with unilateral loss of L6 were examined. The L8 on the side of the L6 loss was compared with the L8 in the hemiarch without L6 loss (contralateral). The effect of L6 loss on the positioning of L8 was examined in all the samples (n=54), whereas the effect on the development of the third molar was examined in 38 patients with L8 with incomplete root formation. The Signs statistical test was used to evaluate the comparison between loss and contralateral hemiarches. Results: In 20 (37%) of 54 subjects, the L8 was better positioned in the hemiarch with loss of the lower first molar (p<0.001) compared with the control side. In the remaining 34 subjects, no difference was found. When only the L8 considered as impacted on the control side was examined (n=30), the cases with better positioning on the side with L6 loss increased to 66.6% (p<0.001). Conclusion: The loss of lower first molars improves the position of the lower third molar during its active eruption, mainly when the lower third molar is impacted. However, L6 loss does not affect the root development of lower third molars. [ABSTRACT FROM AUTHOR]

The paper presents the results of research conducted during 2018-2019, regarding the root nodules formation at soybean, by applying different tillage systems, under the conditions of the Agricultural Research and Development Station Turda situated in the Transylvanian Plain. The development of root nodules in soybean differs from one variety to another, the highest value of 103 nodules/plant is recorded in the Onix variety and lower in the Cristina and Felix variety with 66 and 69 nodules respectively. Also at the weight of the nodules/plant it seems to maintain the same trend, the Onix variety (0.86 g) being superior to the other two varieties (Felix 0.83 g, Cristina 0.80 g). The highest soybean average yield was registered at the Cristina variety cultivated in the minimum tillagechisel (2548 kg/ha) and the lowest yield at the Felix variety in the no tillage (1592 kg/ha). [ABSTRACT FROM AUTHOR]

The paper presents the results of research conducted during 2018-2019, regarding the root nodules formation at soybean, by applying different tillage systems, under the conditions of the Agricultural Research and Development Station Turda situated in the Transylvanian Plain. The development of root nodules in soybean differs from one variety to another, the highest value of 103 nodules/plant is recorded in the Onix variety and lower in the Cristina and Felix variety with 66 and 69 nodules respectively. Also at the weight of the nodules/plant it seems to maintain the same trend, the Onix variety (0.86 g) being superior to the other two varieties (Felix 0.83 g, Cristina 0.80 g). The highest soybean average yield was registered at the Cristina variety cultivated in the minimum tillagechisel (2548 kg/ha) and the lowest yield at the Felix variety in the no tillage (1592 kg/ha). [ABSTRACT FROM AUTHOR]

The purpose of this retrospective study was to evaluate risk factors for external root resorption (ERR) on maxillary second molars (MxM2) in association with impacted third molars (MxM3) using cone beam computed tomography (CBCT) scans. The angles between the axes of MxM2/MxM3 (inclination) were measured. Further, ERR on MxM2 was classified as absent, slight, moderate, or severe. Contact location between MxM3 and MxM2, the size of the dental follicle, type of impaction, root formation, and patient demographic characteristics were also assessed. Half of the 84 MxM2 showed ERR (slight 36.9%, moderate 6.0%, severe 7.1%). Patient age was a significant factor for the presence of ERR (P = 0.03). The inclination was also a relevant factor, with transverse MxM3 exhibiting the highest risk of ERR (P = 0.02). The cervical third (28.6%) showed a significantly lower risk percentage of ERR compared to the apical (73.7%) and middle thirds (60.6%) of the root (P = 0.004). Based on these findings, clinicians assessing the need for surgical removal should be able to selectively identify impacted MxM3 at risk of causing ERR on MxM2 early on, especially when the MxM3 is located in close contact with the apical and middle thirds of the MxM2 roots and has a transverse inclination. [ABSTRACT FROM AUTHOR]

This study compared the effect of a novel zinc containing, Caredyne Shield (CS), and a fluoroaluminocalciumsilicate-based, Nanoseal (NS) desensitizers on dentin tubule occlusion, inhibition of Streptococcus mutans (S. mutans) biofilm growth, and resistance to bacterial demineralization. Desensitizers were applied to simulated hypersensitive bovine dentin, with distilled water used as a control. S. mutans biofilms were grown on the surface of each specimen in an oral biofilm simulator. CS showed the least bacterial count and water insoluble glucan amount followed by NS. Transverse micro radiography revealed that both CS and NS showed significant reduction in mineral loss and lesion depth of the associated lesion. Scanning electron micrographs showed that the two desensitizers formed obvious depositions on the dentin surfaces, occlusion of tubules and mineral tag formation. [ABSTRACT FROM AUTHOR]

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Abstract Introduction The aim of this study was to assess the frequency of root crack formation caused by the use of manual instrumentation, 2 rotary systems, and 1 reciprocating system using light-emitting diode transillumination. Methods One hundred fifty mandibular premolars were randomly divided into 5 groups (n = 30): control 1, no intervention; control 2, instrumented with hand files; group 3, instrumented with ProTaper Universal rotary files (Dentsply Maillefer, Ballaigues, Switzerland); group 4, instrumented with OneShape rotary files (Micro-Mega, Besancon, France); and group 5: instrumented with the WaveOne reciprocal system (Dentsply Maillefer, Ballaigues, Switzerland). After root canal preparations, the roots were sectioned at 3, 6, and 9 mm from the apex with water irrigation. The slices were inspected under a stereomicroscope with light-emitting diode transillumination from the buccal, lingual, mesial, and distal directions at ×40 magnification to determine the presence/absence of cracks (dentinal defects). The chi-square test was used to analyze the data. Results There was a significant difference among the groups in crack frequency (P <.05). The 2 single systems had significantly higher cracks than the other 3 groups. At 3 mm from the apex, there were significantly more cracks in groups 4 and 5 than in groups 1, 2, and 3 (P <.05). At 6 mm from the apex, no significant difference was noted (P >.05). At 9 mm from the apex, the frequency of cracks in group 3 was significantly higher (P <.05). Conclusions According to the results, using rotary instrumentation can result in some dentinal defects, and single-file systems, regardless of motion type, can cause significantly higher crack formation in the apical third of root canals. [ABSTRACT FROM AUTHOR]

The objective of this study was to identify the parasite causing the formation of root hair galls on eelgrass (Zostera marina) in Puget Sound, WA. Microscopic and molecular analyses revealed that a novel protist formed plasmodia that developed into sporangia in root hair tip galls and released biflagellate swimming zoospores. Root hair galls were also observed in the basal section of root hairs, and contained plasmodia or formed thick-walled structures filled with cells (resting spores). Phylogenetic analyses of 18S rDNA sequence data obtained from cells in sporangia indicated that the closest relative of the parasite with a known taxonomic identification was Plasmodiophora diplantherae (86.9% sequence similarity), a phagomyxid parasite that infects the seagrass Halodule spp. To determine the local geographic distribution of the parasite, root and soil samples were taken from four eelgrass populations in Puget Sound and analyzed for root hair galls and parasite DNA using a newly designed qPCR protocol. The percent of root hairs with galls and amount of parasite DNA in roots and sediment varied among the four eelgrass populations. Future studies are needed to establish the taxonomy of the parasite, its effects on Z. marina, and the factors that determine its distribution and abundance. [ABSTRACT FROM AUTHOR]

Endodontic biofilms and the complexity of root canal systems are considered as major causes of primary and secondary root canal infection. Unfortunately, these biofilms contain bacteria which are well within dentinal tubules and are inaccessible to the conventional instrumentation, irrigants, intracanal medicaments, and sealers. Nanoparticles (NPs) are microscopic particles with one or more dimensions in the range of 1-100 nm. It has been observed that the size of nanoparticulates used in disinfection of the root canal, plays an important role in their antibacterial activity by overcoming microbial challenges, mechanical integrity of diseased dentin matrix, and tissue regeneration. This purpose of this review article is to provide the application of various nanoparticles in the control of biofilm formation with the root canal system. [ABSTRACT FROM AUTHOR]

Purpose: Dens invaginatus is a developmental dental malformation generally thought to occur as a result of an infolding of the enamel organ into the dental papilla prior to calcification. This study reports a case of regenerative endodontic procedure of immature type I dens invaginatus with a 4-year follow-up. Case report: A 9-year-old girl was referred to a private dental clinic. Clinical examination revealed fistula on the buccal face of the maxillary left lateral incisor. Radiographic and tomographic images showed incomplete root formation, with extremely thin dentinal walls and the presence of type I dens invaginatus. Regenerative endodontic procedure was chosen because of pulp necrosis. During the access procedure, the dens invaginatus was removed under a clinical microscope using ultrasound. Calcium hydroxide and 2% chlorhexidine gel were used as intracanal medicaments for 14 days. MTA was used for sealing of the middle-cervical thirds and composite resin for coronal sealing. Conclusion: The present report showed the successful regenerative endodontic procedure of immature teeth with type I dens invaginatus using calcium hydroxide and 2% chlorhexidine gel as intracanal dressings for 14 days. The follow-up at 4 years showed no signs and symptoms and the radiographic images showed periodontal tissues in good condition with continuous root formation and apical closure. [ABSTRACT FROM AUTHOR]

Dens evaginatus is a developmental tooth anomaly in which an extra cusp or tubercle protrudes on the occlusal surface of the tooth along with some pulpal tissue. Because of the fragile nature of the protrusion, these teeth are often at risk of pulpal exposure. When this occurs in an immature tooth, regenerative endodontic treatment may be a good treatment approach to promote root formation. There is limited literature that documents the occurrence of orthodontic treatment in teeth that have undergone regenerative endodontic therapy using triple antibiotic paste. Here we present a case of an immature premolar tooth with dens evaginatus that was diagnosed with pulp necrosis and chronic apical abscess. The tooth was treated with regenerative endodontic treatment; after which, the patient received orthodontic treatment with fixed appliances for 2 years. The tooth responded favorably to the regenerative endodontic treatment and orthodontic tooth movement. Clinically and radiographically, all the follow-up examinations revealed an asymptomatic tooth with evidence of periapical healing with stunted root development. The tooth remained asymptomatic even after 4 years. The regenerative endodontic procedure (REP) was successful in treating an immature permanent premolar with pulp necrosis and apical periodontitis with dens evaginatus. In this case, the tooth treated with an REP responded to orthodontic treatment similar to the nonendodontically treated teeth. Further studies are recommended to clarify the precise effects of orthodontic treatment on teeth treated with an REP. [ABSTRACT FROM AUTHOR]

• Black spruce trees formed continuous adventitious roots in water saturated soil. • Highest radial growth was registered in the younger adventitious roots. • Survival strategy: allocation of a higher amount of energy to the root system. Large areas in boreal forests are classified as peatlands, characterized by organic soils with a high water table. Black spruce (Picea mariana (Mill.) B.S.P.) is one of the species capable of growing in this inauspicious environment, where an adaptation of the root system can be expected. We studied young black spruces growing in peat moss with two different hydrological conditions over a 19 years timespan: saturated and well-drained peat. We identified the initial and adventitious roots of the trees and compiled radial growth measurements of each root. The general growth pattern of the roots was identified and compared to the annual radial growth within the stem. We observed growth reductions during the first years after the planting shock, followed by a growth increase in the roots and stems for both hydrological conditions. The continuous formation of adventitious roots in trees growing in the saturated environment was the main adaptation noticed. The largest radial growth values were registered in the younger adventitious roots growing in saturated conditions. The lowest radial growth in the adventitious roots were registered in the well-drained condition. PCA analyses revealed the influence of root depth with regard to stem height and diameter at soil level. The black spruce trees displayed the required plasticity to form adventitious roots outside the range of the water table, allowing them a better access to oxygen and nutrients. This survival strategy implies to allocate a higher amount of energy to the root system instead of the aerial part of the tree in which overall productivity is low. [ABSTRACT FROM AUTHOR]

Any disturbance in the primary tooth can lead to an altered eruption pattern of the corresponding permanent tooth. This article presents a case of a carious permanent second premolar with an immature root that erupted prematurely following extraction of the infected primary second molar. The carious premolar was treated with a stepwise excavation, and a primary stainless steel crown was adapted to prevent microleakage and restoration failure. A follow-up evaluation at 4 years showed remarkable healing and complete root formation. To the authors' knowledge, this is the first case report in the literature that describes successful conservative management of a rootless premolar treated by pulp capping and restored with a primary stainless steel crown. [ABSTRACT FROM AUTHOR]

Nano silver has positive effects on the growth and development of in vitro plants. The current study was carried out to investigate the effect of adding different concentrations of nano silver nitrate (0.0, 1.0, 2.0, 3.0 and 4.0 ml/l) to the culture medium in multiplication and rooting stage of the date palm cv. Hayani. The results showed that there was a significant difference of Ag NPs concentrations in regeneration stage as it increased the number and length of shoots at 3.0 ml/l concentrations compared to the control treatment. The outcome of shoots multiplication experiment indicated that Ag NPs concentration had a significant positive effect on studied traits, when the 3.0 ml/l of Ag NPs added to MS basal medium supplemented with BA at 2.0, GA 3 at 0.5 and NAA at 0.1 (mg/l) gave the highest shoots and leaves number as it reached 10.74 shoots and 30.11 leaf/culture with length 6.60 cm, respectively in comparison with lowest results recorded 2.50 shoot/culture, 10.70 leaf/culture with length 2.00 cm, respectively with the control treatment. All shoots were cultivated in a new medium supplemented with NAA at 1.0 mg/l and various concentrations of Ag NPs to study root formation. The findings indicated that the optimal medium for root formation was one that included Ag NPs at 3.0 ml/l which resulted in the highest rooting percentage (85.4%), root number (8.4 root/culture) with length 6.3 cm. In concentration 3.0 ml/l of Ag NPs recorded that, chlorophyll A, chlorophyll B and carotenoids increases to 1.50, 1.10 and 2.33 (mg/g). Also, occurred increase in carbohydrate content to 26.33 mg/g, the proline was enhanced and increased gradually to 3.31 mg/g and protein content to 0.77 mg/g. • Nano silver has positive effects on the growth and development of in vitro date palm cove. Hayani. • The findings indicated that the optimal medium for root formation, rooting percentage, root number and length. • Chlorophyll A, chlorophyll B, carotenoids, carbohydrate content, proline and protein content were enhanced and increased. [ABSTRACT FROM AUTHOR]

Objective: To assess the association between formation stages of the mandibular third molars and the space distal to the permanent molars (retromolar space). Materials and Methods: The material included pretreatment lateral cephalographs of 96 orthodontic patients (49 males, 47 females; 8-18 years old). The molar formation stage was assessed through the method of Nolla, which rates the degree of calcification on a scale of 10 stages. The retromolar space was measured from the most concave point of the anterior border of the ramus to the distal surface of the first molar (used because the second molars had not yet erupted in the younger patients). Statistical analyses included f-tests and analyses of variance for group differences and the Pearson product moment to gauge associations among variables. Results: The formation stage advanced with age, but wide standard deviations were noted. Similarly, the retromolar distance increased with age and was greatest between 10 and 12 years. The correlation between retromolar space and developmental stage was high (r = 0.85). On average, an increase of 5 mm of retromolar space corresponds to a 1.8 stage in tooth maturation. Conclusions: The correlation between third molar mineralization and available retromolar space essentially represents the association between one biologic age (dental formation) and another growth-related event (mandibular skeletal growth). The findings do not necessarily reflect successful emergence or nonimpaction of the molars. Longitudinal data are needed to determine such outcomes. (Angle Orthod. 2014;84:946-950.) [ABSTRACT FROM AUTHOR]

Ethylene regulates plant root growth and resistance to environment stress. However, the role and mechanism of ethylene signaling in response to Cd stress in rice remains unclear. Here, we revealed that ethylene signaling plays a positive role in the resistance of rice to Cd toxicity. Blocking the ethylene signal facilitated root elongation under normal conditions, but resulted in severe oxidative damage and inhibition of root growth under Cd stress. Conversely, ethylene signal enhancement by EIN2 overexpression caused root bending, similar to the response of roots to Cd stress, and displayed higher Cd tolerance than the wildtype (WT) plants. Comparative transcriptome analysis indicated EIN2-mediated upregulation of genes involved in flavonoid biosynthesis and peroxidase activity under Cd stress. The synthesis of phenolic acids and flavonoids were positively regulated by ethylene. Thus, the ein2 (ethylene insensitive 2) mutants displayed lower ROS scavenging capacity than the WT. Moreover, a significant increase in Cd accumulation and relatively increased apoplastic flow were observed in the root apex of the ein2 mutant compared with the WT plants. Overall, EIN2-mediated Cd resistance in rice is mediated by the upregulation of flavonoid biosynthesis and peroxidase activity to induce ROS scavenging, and apoplastic transport barrier formation reduces Cd uptake. [Display omitted] • Ethylene signal blocking caused severe oxidative damage to roots under Cd stress. • Ethylene signal positively regulated PRX activity to scavenge ROS under Cd stress. • EIN2-mediated Cd resistance is mediated by upregulation of flavonoid synthesis. • EIN2-mediated apoplastic transport barrier formation in roots reduced Cd uptake. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the effects of glucose and glycerol (provided as principal fermentable supplements) on alkaline tolerance and biofilm-forming capabilities of root canal–derived strains of Enterococcus faecalis and those from other environments. The planktonic growth kinetics and the biofilm-forming capabilities of E. faecalis isolates (identified by 16S ribosomal DNA sequencing) were compared when supplied with glucose and glycerol at pH levels of 8 and 11 in a microtiter plate. The metabolic activity of the biofilms plate that formed at a neutral pH level (supplied with either glucose or glycerol) was measured after subsequent adjustment to a pH level of 11. Ten isolates (7 from root canals and 3 from other sources) were examined. The lag phase and the doubling time increased under elevated alkalinity irrespective of either the fermentable supplement (glucose or glycerol) or the origin of the isolate. Biofilm formation and metabolic activity varied among strains, but neither was related to the source of isolation. In general, biofilm formation was enhanced when grown in glucose compared with glycerol and at a pH of 8 compared with a pH of 11 (irrespective of the fermentable supplement). The provision of glycerol did not increase either the planktonic growth rate or biofilm development compared with glucose but significantly increased the metabolic activity of biofilms, especially at a pH of 11 compared with a pH of 8. In the nutrient-deprived environment of a necrotic or root-filled root canal, glycerol may be an alternative energy source that can promote increased metabolic activity of E. faecalis under alkaline treatment conditions. [ABSTRACT FROM AUTHOR]

The article presents a study which compares the biochemical, cytological, and histological effects of cyanobacterial toxins cylindrospermopsin (CYN) and microcystin-LR (MCY-LR) in white mustard seedlings. It states that zone of lateral root formation and apical meristems of main roots were used for cytological analysis. Results show that both CYN and MCY-LR inhibited the full lateral roots development formation.

Abstract: Purple passion fruit is an important fresh table fruit. At present, the production of passion fruit is decreasing because of the spread of viral diseases throughout the planting area. The aim of this research was to propagate virus-free plants using a tissue culture technique involving the apical meristem of purple passion fruit. Shoot tips were excised to a length of 2 mm and the shoots were regenerated by culturing on Murashige and Skoog medium supplemented with different concentrations of benzyladenine (BA) (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mg/l) and 1-naphthaleneacetic acid (NAA) (0.2, 0.5, 1.0, 1.5 and 2.0 mg/l). Root formation was promoted using different concentrations of indole-3-butyric acid (IBA) (0.0, 0.2, 0.4, 0.6, 0.8 and 1.2 mg/l). A greater number of shoots were produced with BA concentrations of 1.0 and 1.5 mg/l than with any other BA concentrations tested (less than 1.0 mg/l or greater than 1.5 mg/l). However, when NAA at any concentration was included in the medium, no shoots were produced in culture. The cultures including 1.0 mg/l and 1.5 mg/l BA were then subcultured four times every two weeks. Initially, the tissue cultured in the 1.5 mg/l BA medium grew faster than that cultured in the 1.0 mg/l BA medium. The tissue cultured with 1.5 mg/l BA generated many short shoots, whereas the tissue cultured with 1.0 mg/l BA, generated long shoots that could be subcultured into individual plants. These regenerated shoots were assayed for the presence of the passion fruit woodiness virus using ELISA or a test strip kit; only virus-free shoots were used for further propagation. Root formation was very good in IBA concentrations of 0.4 and 0.6 mg/l. Thus, virus-free plants could be successfully regenerated directly from the apical meristem. [Copyright &y& Elsevier]

We have developed a two-step procedure for rooting of tea microshoots in vitro. The effectiveness of different auxin treatments for root formation was found to differ. Among the auxins tested, 25 μM α-naphthalene acetic acid (NAA) gave the best results, with 100% rooting, compared to 25 μM indole-3-butyric acid (IBA) or 25 μM indole-3-acetic acid (IAA), which induced 17% and 58% rooting, respectively. Incubation of tea microshoots on 0.33X Murashige and Skoog (MS) medium, supplemented with 25.0 μM NAA or 175.0 μM IBA for 10 d, followed by transfer to auxin-free 0.33X MS medium resulted in 100% rooting, whereas 50.0 μM IAA induced 91.7% rooting. Besides the different auxin treatments, the strength of the MS medium, the duration of incubation of microshoots in auxin-containing medium, the sucrose concentration, the gelling agent, the pH of the medium, the incubation temperature, the light intensity, and the quality of the shoots also played a significant role during in vitro rooting of micropropagated tea shoots. Among the combinations tested, the most effective results were obtained when green microshoots were incubated on 0.33X MS medium supplemented with 25.0 μM NAA, 50.0 mM sucrose, pH 5.5, gelled with 0.2% (w/v) Phytagel™ for 10 d at 25° - 30°C at a light intensity of 40 μmol m-2 s-1, followed by transfer of shoots to auxin-free 0.3X MS medium. This resulted in 100% rooting and, on average, 11 long roots were formed per shoot. Anatomical changes during adventitious rooting of micropropagated tea shoots in vitro were also studied to understand the process of rooting. [ABSTRACT FROM AUTHOR]

Abstract: The effects of ethephon on the constitutive aerenchyma formation in roots were studied with a rice variety Yangdao 6 as material. The number of air spaces formed by disintegrated cells in mediopellis increased significantly with the rising ethephon concentrations, whereas superoxide dismutase (SOD) activity showed downward trends. Compared with the control, the expression levels of xyloglucan endotransglycosylase (XET) gene were markedly higher both at the apical 10 mm and distal parts of roots in 100 mg/L ethephon treated plants. The accumulation of XET was supposed to be associated with the aerenchyma development. Furthermore, earlier cortical cell death was observed under the ethephon treatments, and most of nuclei of cells at 4 mm from the root apex disintegrated with many Golgi apparatus, mitochondria and membrane- bound vesicles around the cell wall. [Copyright &y& Elsevier]

At low concentrations zinc (Zn) is essential for plants and animals, but it becomes toxic when it exceeds a critical level. This study aimed to explore the effects of biochar on the remediation of Zn-polluted soil and the distribution of Zn in rice plants using pot experiments. Various amounts of biochar (0% (control), 2.5%, and 5% w/w) derived from rice straw were mixed with Zn-contaminated soil collected from farmland near a mine. The results showed that biochar enhanced the biomass of rice tissues and significantly reduced the concentration of Zn in brown rice. These results could be attributed to the combination of several effects: (1) Biochar increased the soil pH and organic carbon content, resulting in a reduction in the concentration of soil available Zn and transforming forms of immobilized Zn from acid soluble to reducible. (2) Biochar addition decreased the amorphous iron and complex iron concentrations in the soil solution and reduced the formation of root Fe plaques as well as the storage of Zn in iron plaques, thus diminishing the probability of Zn transfer from root surfaces to tissues. (3) Biochar played a key role in abating the toxic effect of Zn in rice plants as it decreased the transfer of Zn from roots to leaves and promoted Zn storage in the vacuoles of root cells. These results suggest that the application of biochar to Zn-contaminated soil is effective in reducing Zn accumulation in rice grains and can enhance rice production. [Display omitted] • Biochar enhanced plant biomass and decreased Zinc (Zn) accumulation in rice grain. • Biochar decreased the bioavailability of Zn in soils. • Biochar reduced the storage of Zn in iron plaques. • Biochar reduced the transfer of Zn from root to leaf. [ABSTRACT FROM AUTHOR]

Bensulfuron-methyl (BSM) residues in soil threaten the rotation of BSM-sensitive crops. Microbial biofilms formed on crop roots could improve the ability of microbes to survive and protect crop roots. However, the research on biofilms with the purpose of mitigating or even eliminating BSM damage to sensitive crops is very limited. In this study, one BSM-degrading bacterium, Hansschlegelia zhihuaiae S113, colonized maize roots by forming a biofilm. Root exudates were associated with increased BSM degradation efficiency with strain S113 in rhizosphere soil relative to bulk soil, so the interactions among BSM degradation, root exudates, and biofilms may provide a new approach for the BSM-contaminated soil bioremediation. Root exudates and their constituent organic acids, including fumaric acid, tartaric acid, and l -malic acid, enhanced biofilm formation with 13.0–22.2% increases, owing to the regulation of genes encoding proteins responsible for cell motility/chemotaxis (fla/che cluster) and materials metabolism, thus promoting S113 population increases. Additionally, root exudates were also able to induce exopolysaccharide production to promote mature biofilm formation. Complete BSM degradation and healthy maize growth were found in BSM-contaminated rhizosphere soil treated with wild strain S113, compared to that treated with loss-of-function mutants ΔcheA -S113 (89.3%, without biofilm formation ability) and ΔsulE -S113 (22.1%, without degradation ability) or sterile water (10.7%, control). Furthermore, the biofilm mediated by organic acids, such as l -malic acid, exhibited a more favorable effect on BSM degradation and maize growth. These results showed that root exudates and their components (such as organic acids) can induce the biosynthesis of the biofilm to promote BSM degradation, emphasizing the contribution of root biofilm in reducing BSM damage to maize. [Display omitted] • Strain S113 can degrade BSM, but also forms a biofilm on maize root surface. • Root exudates enhance S113 biofilm formation by different mechanisms. • Adding L-malic acid to induce biofilm formation increases BSM bioremediation efficiency. • Biofilm formation on roots by S113 promoted the elimination of BSM injury to maize. [ABSTRACT FROM AUTHOR]

The article presents a study on the synthesis of the new fluorinated auxin, 4-triflouromethylindole-3-acetic acid (4-CF3-IAA) for the development of new compounds for the root formation of tree cuttings. It says that a strong root formation-promoting activity was shown by (4-CF3-IAA) through bioassay. However, several factors including chemical stability, facility for transport, and metabolic stability may influence the auxin activity of compounds.

Abstract: Fine roots are the most important plant organs for water and nutrient acquisition. Water and ion uptake is most sensitively altered by the formation of new roots in favourable sites. Fine root turnover, i.e. shedding and replacing fine roots, is therefore important in maximizing root system efficiency. Some evidence exists that accelerating fine root turnover is appropriate to counterbalance negative effects caused by drought albeit formation of new roots in drying soil is a high-risk investment. In the present study, fine root (≤2mm diameter) dynamics in a stand of mature Fagus sylvatica (European beech) was observed during summer 2003 that was extraordinary dry in Central Europe. Depth-related fine root formation and mortality (between 3.4 and 41.6cm soil depth) were observed and related to soil water content and soil temperature. The environmental parameters measured appeared as significant but surprisingly weak determinants for fine root formation and none of them influenced fine root mortality significantly. Fine root mortality was not counterbalanced by root formation but pronounced fine root shedding was found for non-suberized and superficial fine roots. Despite severe soil drying, fine roots were primarily invested in upper and thus unfavourable soil strata. The fine root system of F. sylvatica underlay an almost continuous replacement but there was no evidence for altered fine root turnover as an important response to soil drying. Rather the relative conservative fine root investment pattern and the large losses of fine roots indicate high construction costs at low benefits on the whole plant level and thus may limit the vigour of F. sylvatica if comparable drought periods occur frequently. [Copyright &y& Elsevier]