Genetic diversity and structure in hill rice (Oryza sativa L.) landraces from the North-Eastern Himalayas of India.

BACKGROUND: Hill rices (Oryza sativa L.) are direct seeded rices grown on hill slopes of different gradients. These landraces have evolved under rainfed and harsh environmental conditions and may possess genes governing adaptation traits such as tolerance to cold and moisture stress. In this study, 64 hill rice landraces were collected from the state of Arunachal Pradesh of North-Eastern region of India, and assessed by agro-morphological variability and microsatellite markers polymorphism. Our aim was to use phenotypic and genetic diversity data to understand the basis of farmers' classification of hill rice landraces into two groups: umte and tening. Another goal was to understand the genetic differentiation of hill rices into Indica or japonica subspecies. RESULTS: According to farmers' classification, hill rices were categorized into two groups: umte (large-grained, late maturing) and tening (small-grained, early maturing). We did not find significant difference in days to 50 % flowering between the groups. Principal component analysis revealed that two groups can be distinguished on the basis of kernel length-to-width ration (KLW), kernel length (KL), grain length (GrL), grain length-to-width ration (GrLW) and plant height (Ht). Stepwise canonical discriminant analysis identified KL and Ht as the main discriminatory characters between the cultivar groups. Genetic diversity analysis with 35 SSR markers revealed considerable genetic diversity in the hill rice germplasm (gene diversity: 0.66; polymorphism information content: 0.62). Pair-wise allelic difference between umte and tening groups was not statistically significant. The model-based population structure analysis showed that the hill rices were clustered into two broad groups corresponding to Indica and Japonica. The geographic distribution and cultivars grouping of hill rices were not congruent in genetic clusters. Both distance- and model-based approaches indicated that the hill rices were predominantly japonica or admixture among the groups within the subspecies. These findings were further supported by combined analysis hill rices with 150 reference rice accessions representing major genetic groups of rice. CONCLUSION: This study collected a valuable set of hill rice germplasm for rice breeding and for evolutionary studies. It also generated a new set of information on genetic and phenotypic diversity of hill rice landraces in North-Eastern region of India. The collected hill rices were mostly japonica or admixture among the subpopulations of Indica or Japonica. The findings are useful for utilization and conservation of hill rice germplasm.

Stress-inducible expression of AtDREB1A transcription factor greatly improves drought stress tolerance in transgenic indica rice.

The cultivation of rice (Oryza sativa L.), a major food crop, requires ample water (30 % of the fresh water available worldwide), and its productivity is greatly affected by drought, the most significant environmental factor. Much research has focussed on identifying quantitative trait loci, stress-regulated genes and transcription factors that will contribute towards the development of climate-resilient/tolerant crop plants in general and rice in particular. The transcription factor DREB1A, identified from the model plant Arabidopsis thaliana, has been reported to enhance stress tolerance against drought stress. We developed transgenic rice plants with AtDREB1A in the background of indica rice cultivar Samba Mahsuri through Agrobacterium-mediated transformation. The AtDREB1A gene was stably inherited and expressed in T1 and T2 plants and in subsequent generations, as indicated by the results of PCR, Southern blot and RT-PCR analyses. Expression of AtDREB1A was induced by drought stress in transgenic rice lines, which were highly tolerant to severe water deficit stress in both the vegetative and reproductive stages without affecting their morphological or agronomic traits. The physiological studies revealed that the expression of AtDREB1A was associated with an increased accumulation of the osmotic substance proline, maintenance of chlorophyll, increased relative water content and decreased ion leakage under drought stress. Most of the homozygous lines were highly tolerant to drought stress and showed significantly a higher grain yield and spikelet fertility relative to the nontransgenic control plants under both stressed and unstressed conditions. The improvement in drought stress tolerance in combination with agronomic traits is very essential in high premium indica rice cultivars, such as Samba Mahsuri, so that farmers can benefit in times of seasonal droughts and water scarcity.

Evaluating ChatGPT to test its robustness as an interactive information database of radiation oncology and to assess its responses to common queries from radiotherapy patients: A single institution investigation.

PURPOSE: Commercial vendors have created artificial intelligence (AI) tools for use in all aspects of life and medicine, including radiation oncology. AI innovations will likely disrupt workflows in the field of radiation oncology. However, limited data exist on using AI-based chatbots about the quality of radiation oncology information. This study aims to assess the accuracy of ChatGPT, an AI-based chatbot, in answering patients' questions during their first visit to the radiation oncology outpatient department and test knowledge of ChatGPT in radiation oncology. MATERIAL AND METHODS: Expert opinion was formulated using a set of ten standard questions of patients encountered in outpatient department practice. A blinded expert opinion was taken for the ten questions on common queries of patients in outpatient department visits, and the same questions were evaluated on ChatGPT version 3.5 (ChatGPT 3.5). The answers by expert and ChatGPT were independently evaluated for accuracy by three scientific reviewers. Additionally, a comparison was made for the extent of similarity of answers between ChatGPT and experts by a response scoring for each answer. Word count and Flesch-Kincaid readability score and grade were done for the responses obtained from expert and ChatGPT. A comparison of the answers of ChatGPT and expert was done with a Likert scale. As a second component of the study, we tested the technical knowledge of ChatGPT. Ten multiple choice questions were framed with increasing order of difficulty - basic, intermediate and advanced, and the responses were evaluated on ChatGPT. Statistical testing was done using SPSS version 27. RESULTS: After expert review, the accuracy of expert opinion was 100%, and ChatGPT's was 80% (8/10) for regular questions encountered in outpatient department visits. A noticeable difference was observed in word count and readability of answers from expert opinion or ChatGPT. Of the ten multiple-choice questions for assessment of radiation oncology database, ChatGPT had an accuracy rate of 90% (9 out of 10). One answer to a basic-level question was incorrect, whereas all answers to intermediate and difficult-level questions were correct. CONCLUSION: ChatGPT provides reasonably accurate information about routine questions encountered in the first outpatient department visit of the patient and also demonstrated a sound knowledge of the subject. The result of our study can inform the future development of educational tools in radiation oncology and may have implications in other medical fields. This is the first study that provides essential insight into the potentially positive capabilities of two components of ChatGPT: firstly, ChatGPT's response to common queries of patients at OPD visits, and secondly, the assessment of the radiation oncology knowledge base of ChatGPT.

Salivary and urinary assessment of fluoride and silver ion concentrations after silver diamine fluoride application in children: a prospective cohort study.

PURPOSE: The purpose of the study was to determine the fluoride (F) and silver (Ag) ions levels in the saliva and urine of healthy children after silver diamine fluoride (SDF) application on dental carious lesions. METHODS: Sixty children (4-6 years with ≥ 3 caries lesions) were recruited from the outpatient department of Pediatric Dentistry. From each child, 3 ml unstimulated saliva samples were collected at baseline, one hour, and 24 h after SDF application. Similarly, 3 ml urine samples were collected prior to and after 24 h of SDF application. F and Ag ion concentrations were determined by fluoride ion-selective electrode (ISE) and inductively coupled plasma mass spectrometry (ICPMS), respectively. RESULTS: The mean ± standard deviation (SD) baseline, 1-h, and 24-h salivary F concentrations (ppm) were 0.07 ± 0.07, 0.93 ± 0.48, and 0.19 ± 0.19, respectively, while the mean baseline and 24-h urinary F concentrations (ppm) were 0.33 ± 0.20 ppm and 0.43 ± 0.25 ppm, respectively. The mean baseline, 1-h, and 24-h salivary Ag concentrations (ppb) were 4.22 ± 3.15, 4198 ± 350, and 56.93 ± 37, respectively. The mean baseline and 24-h urinary Ag concentrations (ppb) were 2.80 ± 2.93 ppb and 4.72 ± 4.0 ppb, respectively. There were statistically elevated F and Ag ion concentrations at 1 h and 24 h after SDF application as compared to the baseline. CONCLUSION: Salivary and urinary F and Ag ions concentrations elevated significantly at 24 h following SDF applications in children. A significant high recovery of these ions in urine indicates minimal systemic absorption, thus intermittent topical application of 38% SDF has a minimal risk of toxicity.

Efficacy of periarticular local infiltrative anaesthesia (modified Ranawat cocktail regimen) for postoperative pain control and reducing morbidity in total knee arthroplasty: a tertiary centre retrospective study.

INTRODUCTION: surgical pain is managed with multi-modal anesthesia in total knee arthroplasty (TKA). It is dubious whether including local infiltrative anaesthesia (LIA) before wound closure provides adequate pain control and decreases morbidity. MATERIAL AND METHODS: this was a retrospective conducted to assess postoperative pain control, morbidity index, and opioid consumption in 116 patients who underwent TKA and were divided into two groups based on LIA (Modified Ranawat Regimen) or normal saline infiltration in the wound. RESULTS: the mean NRS score was significantly lower in LIA group (3.2) as compared to the control group (3.9) in the first 24 hours. Functional milestones were relatively achieved earlier in LIA group but the values were not significant. Tramadol consumption was remarkably higher in the control group as compared to LIA group on day 1 and 2. As per the morbidity index the mean score on day one was 16.18 and 23.40 which decreased to 6.37 and 9.21 by day three in LIA and control group respectively indicating morbidity has decreased but more so in LIA group. CONCLUSION: our study concludes that use of modified cocktail regimen in the knee effectively decreased morbidity with excellent to good results, declining NRS score, minimal rescue analgesia requirement, early ambulation with better safety.

INTRODUCCIÓN: el dolor quirúrgico se trata con anestesia multimodal en la artroplastia total de rodilla (ATR). Es dudoso que incluir anestesia local infiltrativa (LIA) antes del cierre de la herida proporcione un control adecuado del dolor y disminuya la morbilidad. MATERIAL Y MÉTODOS: se realizó una retrospectiva para evaluar el control del dolor posoperatorio, el índice de morbilidad y el consumo de opioides en 116 pacientes sometidos a ATR y se dividieron en dos grupos según el LIA (régimen de Ranawat modificado) o la infiltración de solución salina normal en la herida. RESULTADOS: la puntuación media NRS fue significativamente menor en el grupo LIA (3.2) en comparación con el grupo control (3.9) en las primeras 24 horas. Los hitos funcionales se alcanzaron relativamente antes en el grupo LIA, pero los valores no fueron significativos. El consumo de tramadol fue notablemente mayor en el grupo de control en comparación con el grupo de LIA los días 1 y 2. Según el índice de morbilidad, la puntuación media el día uno fue 16.18 y 23.40, que disminuyó a 6.37 y 9.21 en el día tres en el grupo de LIA y control, respectivamente, lo que indica que la morbilidad ha disminuido, pero más en el grupo LIA. CONCLUSIÓN: nuestro estudio concluye que el uso de un régimen de cóctel modificado en la rodilla disminuyó efectivamente la morbilidad con resultados excelentes a buenos, una disminución de la puntuación NRS, un requisito mínimo de analgesia de rescate y una deambulación temprana con mayor seguridad.

Comparative evaluation of cranberry extract and sodium fluoride as mouth rinses on S. mutans counts in children: a double-blind randomized controlled trial.

BACKGROUND: Recently, research in the field of caries prevention is emphasizing upon identification of edible non-toxic compounds that can interfere with the formation of cariogenic biofilm. AIM: This trial aimed to assess the effectiveness of non-dialyzable material (NDM) containing cranberry mouth rinse (C-MR) on the Streptococcus mutans (S. mutans) counts and compare with that of a sodium fluoride (F-MR) mouth rinse. METHODS: 280 children (8-12 years old) were enrolled in this double-blind single center, parallel, one-month, IRB/IEC approved non-inferiority trial. The participants fulfilling the inclusion criteria were randomly allocated into one of the two groups: C-MR and F-MR. All participants were given verbal and written instructions about at-home mouth-rinsing regimen under parental supervision for a month. Dental plaque samples were collected before and after a month of mouth-rinsing and subjected to culture techniques. S. mutans counts were assessed and compared in both groups. Primary outcome was the difference in the S. mutans counts between two interventions. Both intention-to-treat (ITT) and per-protocol analysis were carried out using two-sample t test with equal variance. RESULTS: The mean S. mutans counts (after log transformation) in C-MR group were: 14.66 (90% CI 14.4,14.9) at baseline and 12.85 (90% CI 12.5, 13.2) colony-forming units/ml (CFU/ml) at one-month post intervention (p = 0.001); while these counts were 14.69 (90% CI 14.5, 14.9) at baseline and 12.71 (90% CI 12.3, 13.1) at one-month intervention in F-MR groups (p = 0.001). ITT analysis showed an inter- group difference of 0.14 CFU/ml (90% CI - 0.32,0.59) in post-SM counts between groups (p = 0.629). CONCLUSION: The study demonstrated that the cranberry mouth rinse was non-inferior to the fluoride mouth rinse in terms of S. mutans levels change. Cranberry-based mouth rinse can be used effectively to reduce the S. mutans counts in children. TRIAL REGISTRATION: Registration number in case of Clinical Trials-CTRI/2019/05/019395.

Description of Stenotrophomonas sepilia sp. nov., isolated from blood culture of a hospitalized patient as a new member of Stenotrophomonas maltophilia complex.

Stenotrophomonas sepilia strain SM16975 (= JCM 32102; = KCTC 62052) is a new species isolated from the blood culture of a hospitalized patient. The biochemical characterization, phenotypic criteria, phylogenomic reconstruction, and genomic analysis were carried out to differentiate it from its phylogenetic neighbours, establishing novel species status in the genus Stenotrophomonas and within Stenotrophomonas maltophilia complex (Smc).

Plastid transformation in eggplant (Solanum melongena L.).

We have developed a method for plastid transformation in eggplant (Solanum melongena L.), a solanaceous plant species. Plastid transformation in eggplant was achieved by bombardment of green stem segments with pPRV111A plastid expression vector carrying the aadA gene encoding aminoglycoside 3''-adenylyltransferase. Biolistic delivery of the pPRV111A plasmid yielded transplastomic plants at a frequency of two per 21 bombarded plates containing 25 stem explants each. Integration of the aadA gene in the plastome was verified by PCR analysis and also by Southern blotting using 16S rDNA (targeting sequence) and the aadA gene as a probe. Transplastomic expression of the aadA gene was verified by RT-PCR. The development of transplastomic technology in eggplant may open up exciting possibilities for novel gene introduction and expression in the engineered plastome for agronomic or pharmaceutical traits.

Natural history of solitary cerebral cysticercosis cases after albendazole therapy: a longitudinal follow-up study from India.

OBJECTIVES: To find out natural course of solitary cerebral cysticercosis (SCC) cases after treating them with 2 weeks albendazole therapy. MATERIAL AND METHODS: All patients with SCC were treated with 2 weeks of albendazole therapy with follow-up radiological scan at 6 months and 2 years. The evolution of lesion was noted as complete resolution, calcification or persistent active. Antiepileptic drugs (AED) prophylaxis was given for 1 year in patients with complete resolution and for 2 years in calcified lesion, respectively. AED was continued in persistent lesion group till it became calcified or resoluted completely. One-year follow-up was done in all after stopping AED. RESULTS: Among 345 cases, 226 (65.5%) had complete resolution with very low seizure relapse rate with 1 year of seizure free period on AED treatment. On the contrary, 105 (30.5%) had calcified lesion with high seizure relapse rate after stopping AED treatment with 2 years of seizure free period. Fourteen patients (4%) could not stop their antiepileptic medication at all because of active lesion. CONCLUSION: Two-third of patients with SCC have favorable outcome with complete resolution and needs short-term AED prophylaxis and the rest one-third requires long AED treatment to prevent seizures.

In vivo remineralization of artificial enamel carious lesions using a mineral-enriched mouthrinse and a fluoride dentifrice: a polarized light microscopic comparative evaluation.

BACKGROUND: Remineralization process is accelerated by the presence of fluoride ions in the oral environment, but this mechanism of caries reversal will be further enhanced if the concentration of calcium, phosphate and fluoride ions is supersaturated with respect to that of oral fluids. AIM: This in vivo study was carried out to evaluate and compare the remineralizing efficacy of a urea-based mineral-enriched mouthrinse and a fluoridated dentifrice using an in vivo intraoral appliance model and polarized light microscopic evaluation technique. MATERIALS AND METHODS: The specimens were prepared from sound teeth and artificial caries was produced using an artificial caries medium in vitro and enamel specimens were inserted in removable orthodontic appliances that were to be worn by 14 children of 10-15 years of age. They were divided into three groups - nonfluoridated dentifrice, fluoridated dentifrice and mineral-enriched mouthrinse groups. After the 6-month experimental period, during which the enamel specimens inserted in the intraoral appliance were subjected to one of the agents (either fluoride, nonfluoride dentifrice or mouthrinse) in vivo, the specimens were retrieved from the patients and were evaluated using the polarized light microscopic technique. OBSERVATIONS AND RESULTS: On analysis, mineral gain occurred in all groups, viz. nonfluoride dentifrice group, fluoride dentifrice and mineral-enriched mouthrinse group. However, it was found to be complete in the mouthrinse group, i.e. both at the surface and at the subsurface (67%), while in the fluoridated dentifrice group, 43% of the samples showed mineral gain in both zones. In the nonfluoridated dentifrice group also, remineralization occurred but was limited either to the surface or the subsurface zone. CONCLUSIONS: Urea-based mineral-enriched mouthrinse was shown to be more efficacious in the process of remineralization of artificial carious lesions.

Inhibition of TNF-alpha-induced cyclooxygenase-2 expression by Mycobacterium bovis BCG in human alveolar epithelial A549 cells.

Cyclooxygenase-2 (COX-2) is implicated in pathophysiological processes associated with the initiation or maintenance of host inflammatory responses to infection. Our results demonstrates that Mycobacterium bovis BCG (M. bovis BCG) downregulates tumour necrosis factor-alpha (TNF-alpha)-induced COX-2 gene expression in alveolar epithelial cells by inhibiting the phosphorylations of Raf-1 and p38 kinases. Further, M. bovis BCG-mediated inhibition of COX-2 or p38 mitogen-activated protein kinase could be reversed by Calyculin A, a selective inhibitor of Ser/Thr phosphatases. Moreover, M. bovis BCG inhibited the TNF-alpha-triggered NF-kappaB activation following IkappaB degradation. Taken together, these results suggest that the attenuation of COX-2 expression by vaccine strain, M. bovis BCG, represents a novel strategy to maintain robust host proinflammatory responses to subsequent challenges with virulent tuberculosis bacilli.

Development of satranidazole mucoadhesive gel for the treatment of periodontitis.

The aim of the paper was to develop satranidazole-containing mucoadhesive gel for the treatment of periodontitis. Different mucoadhesive gels were prepared, using various gelling agents like sodium carboxymethylcellulose (SCMC), poloxamer 407, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, and the mucoadhesive polymer carbopol 934P. The selected formulations (based on the mucoadhesive force) were studied for different mechanical properties, such as mucoadhesive strength, hardness, compressibility, adhesiveness, and cohesiveness through Texture Profile Analyzer. In vitro satranidazole release from the prepared formulations was also determined and compared with marketed preparation of metronidazole (Metrogyl gel). The formulation SC30 (containing SCMC 3% w/v) showed maximum mucoadhesive strength (167.72 +/- 3.76 g) and adhesiveness (-46.23 +/- 0.34 N mm), with low hardness (9.81 +/- 0.04 N) and compressibility (40.05 +/- 0.48 N mm) and moderate cohesiveness (0.87 +/- 0.01). SC30 formulation exhibited long-term release. Thus, SC30 gel was evaluated for its clinical effectiveness along with marketed metronidazole gel. At the end of the study (42 days of clinical studies), both formulations were found to significantly reduce the probing depth, plaque index, gingival index, calculus criteria, and bleeding index. However, the SC30 gel was more effective in reducing the above parameters than marketed metronidazole gel. This study confirmed the acceptability and effectiveness of satranidazole gel for treatment of periodontitis.

Sleep seizures versus wake seizures: a comparative hospital study on clinical, electroencephalographic and radiological profile.

BACKGROUND: Epileptic seizures, predominantly or exclusively during sleep had been the focus of attention for many electroencephalographers. Though few epileptic syndromes are associated with sleep seizures (SS) its frequencies in Indian patients is still unknown. AIM: To find out the patterns of epilepsies in patients having SS and compare them with patients having wake seizures (WS). SETTING AND DESIGN: Open label hospital based study. MATERIALS AND METHODS: One hundred and forty-four (13%) patients having predominantly SS were compared with 976 (87%) patients of WS by various clinical, electrophysiological and radiological factors. STATISTICAL ANALYSIS: Chi square test and student T test, using software SPSS (version 10, 1999) was applied to compare various parameters. Relative risk was calculated by 2 x 2 contingency table. RESULTS: The seizure semiology was better defined in patients with WS and GTCS was more common in SS (P=0.001). Wake-electroencephalogram (EEG) was abnormal in significantly (P=0.001) higher number of patients with WS. Symptomatic etiologies were found in more than half patients. Left lobe involvement was more common in patients having SS (P=0.000). After symptomatic, idiopathic generalized and frontal lobe epilepsy were most frequent with SS. Undetermined epilepsy was found in 37 (25.7%) patients with SS. CONCLUSION: Epilepsies associated with SS were less frequent and had symptomatic cause in most cases. Left hemispherical and frontal lobe lesion were more commonly associated with SS. Frontal lobe and idiopathic generalized epilepsy was most frequent in patients of SS. Sleep EEG should always be done in patients with sleep seizures.

Two-tier system of epilepsy evaluation: a useful method for developing countries.

PURPOSE: To test the usefulness of a simplified and clinically oriented, the Epidemiological Classification (EC), in determination of seizure types and appropriate drug selection in epileptic patients at the primary care level. METHODS: The EC was applied to all epileptic patients over 5 years then compared with the currently recommended international classifications of seizures and epilepsy (ICES/ICEES). RESULTS: A total of 1176 patients were enrolled with 2:1 male preponderance and 88% had onset of disease below 30 years of age. Based on EC, 682 (58%) had partial, 333 (28.3%) had generalized and 161 (13.7%) had undetermined seizures semiology. When ICES was applied, seizure typing was same in 86.2%, 68.5% and 26.7% patients of partial, generalized and unclassified seizures respectively. About 87% patients in generalized and partial seizure semiology had no change in selected antiepileptic drug even after the ICES, but 53.6% patients in undetermined group had change in selected AED. Only, 146 patients (12.5%) found to have symptomatic cause for seizure(s) on applying the EC system. After utilizing the ICEES on 1030 patients (87.5%) of "unknown etiology" cases after the EC system, almost 86.5% patients could be classified to a definite etiological class. CONCLUSION: The EC was found useful for determination of seizure type and appropriate AEDs selection at the primary care level. The ICES/ICEES works better at the tertiary care level. This "two-tier" system can be more effective for overall epilepsy management in developing countries with limited facilities.

Correction: Evaluation of 19,460 Wheat Accessions Conserved in the Indian National Genebank to Identify New Sources of Resistance to Rust and Spot Blotch Diseases.

[This corrects the article DOI: 10.1371/journal.pone.0167702.].

Evaluation of 19,460 Wheat Accessions Conserved in the Indian National Genebank to Identify New Sources of Resistance to Rust and Spot Blotch Diseases.

A comprehensive germplasm evaluation study of wheat accessions conserved in the Indian National Genebank was conducted to identify sources of rust and spot blotch resistance. Genebank accessions comprising three species of wheat-Triticum aestivum, T. durum and T. dicoccum were screened sequentially at multiple disease hotspots, during the 2011-14 crop seasons, carrying only resistant accessions to the next step of evaluation. Wheat accessions which were found to be resistant in the field were then assayed for seedling resistance and profiled using molecular markers. In the primary evaluation, 19,460 accessions were screened at Wellington (Tamil Nadu), a hotspot for wheat rusts. We identified 4925 accessions to be resistant and these were further evaluated at Gurdaspur (Punjab), a hotspot for stripe rust and at Cooch Behar (West Bengal), a hotspot for spot blotch. The second round evaluation identified 498 accessions potentially resistant to multiple rusts and 868 accessions potentially resistant to spot blotch. Evaluation of rust resistant accessions for seedling resistance against seven virulent pathotypes of three rusts under artificial epiphytotic conditions identified 137 accessions potentially resistant to multiple rusts. Molecular analysis to identify different combinations of genetic loci imparting resistance to leaf rust, stem rust, stripe rust and spot blotch using linked molecular markers, identified 45 wheat accessions containing known resistance genes against all three rusts as well as a QTL for spot blotch resistance. The resistant germplasm accessions, particularly against stripe rust, identified in this study can be excellent potential candidates to be employed for breeding resistance into the background of high yielding wheat cultivars through conventional or molecular breeding approaches, and are expected to contribute toward food security at national and global levels.

Genetic Diversity and Population Structure in Aromatic and Quality Rice (Oryza sativa L.) Landraces from North-Eastern India.

The North-eastern (NE) India, comprising of Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim and Tripura, possess diverse array of locally adapted non-Basmati aromatic germplasm. The germplasm collections from this region could serve as valuable resources in breeding for abiotic stress tolerance, grain yield and cooking/eating quality. To utilize such collections, however, breeders need information about the extent and distribution of genetic diversity present within collections. In this study, we report the result of population genetic analysis of 107 aromatic and quality rice accessions collected from different parts of NE India, as well as classified these accessions in the context of a set of structured global rice cultivars. A total of 322 alleles were amplified by 40 simple sequence repeat (SSR) markers with an average of 8.03 alleles per locus. Average gene diversity was 0.67. Population structure analysis revealed that NE Indian aromatic rice can be subdivided into three genetically distinct population clusters: P1, joha rice accessions from Assam, tai rices from Mizoram and those from Sikkim; P2, aromatic rice accessions from Nagaland; and P3, chakhao rice germplasm from Manipur [corrected]. Pair-wise FST between three groups varied from 0.223 (P1 vs P2) to 0.453 (P2 vs P3). With reference to the global classification of rice cultivars, two major groups (Indica and Japonica) were identified in NE Indian germplasm. The aromatic accessions from Assam, Manipur and Sikkim were assigned to the Indica group, while the accessions from Nagaland exhibited close association with Japonica. The tai accessions of Mizoram along with few chakhao accessions collected from the hill districts of Manipur were identified as admixed. The results highlight the importance of regional genetic studies for understanding diversification of aromatic rice in India. The data also suggest that there is scope for exploiting the genetic diversity of aromatic and quality rice germplasm of NE India for rice improvement.