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1.
J Laparoendosc Adv Surg Tech A ; 33(11): 1081-1087, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37844063

ABSTRACT

Objective: To determine the importance of a critical view of safety (CVS) techniques and Rouviere's sulcus (RS) in laparoscopic cholecystectomy (LC) and its relation to biliary duct injuries (BDIs) and to determine the frequency and the type of RS. Design, Setting, and Participants: A descriptive study was carried out among 76 patients presenting to the surgery department of a tertiary care center in Nepal. The study population included all patients in the age group 16-80 years undergoing LC. Outcome Measures: The main outcome of interest was to calculate the percentage of BDIs along with the frequency and the type of RS. Results: A total of 76 patients were enrolled in the study, out of which 57(75%) were female patients with a male-to-female ratio of 1:3 and a mean age of 45.87 ± 15.33 years. Seventy-one (93.4%) patients were diagnosed with symptomatic gallstone disease. The CVS was achieved in 75 (98.7%) of the cases, whereas in 1 case, the CVS could not be achieved, and in the same patient routine LC was converted into open cholecystectomy owing to the difficult laparoscopic procedure. In 56 (73.7%) cases, RS was first visible to the operating surgeons after port installation, alignment, and adequate traction of the gallbladder; in 20 (26.3%) cases, RS was not originally apparent. Conclusion: According to the findings of this study and the literature's critical assessment of safety, this method will soon become a gold standard for dissecting gall bladder components. The technique needs to be extended further, especially for training purposes. Major difficulties can be avoided by identifying RS before cutting the cystic artery or duct during LC.


Subject(s)
Bile Duct Diseases , Cholecystectomy, Laparoscopic , Cholelithiasis , Humans , Male , Female , Adult , Middle Aged , Adolescent , Young Adult , Aged , Aged, 80 and over , Cholecystectomy, Laparoscopic/methods , Gallbladder , Cholelithiasis/surgery , Dissection , Hepatic Artery , Bile Duct Diseases/surgery
2.
J Nepal Health Res Counc ; 21(2): 238-242, 2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38196214

ABSTRACT

BACKGROUND: Oral Pathology curriculum is taught as didactic lectures which promotes rote learning. This study intends to introduce and assess the impact of Case based Learning in student's performance and to obtain the perception of students towards it. METHODS: This cross-sectional study was conducted from March 2021 to January 2022 among dental undergraduate students (N=25) of Gandaki Medical College, Pokhara. The syllabus of Potentially Malignant Oral Lesions and Oral Cancer were covered for BDS third year students by didactic lectures, followed by Case Based Learning sessions (session I- Oral Leukoplakia, session II- Oral Squamous Cell Carcinoma). A pre-test and post-test, containing Multiple Choice questions relevant to the topics, were administered before and after the interventions. Students' perceptions were collected using feedback questionnaire. The scores obtained in the pre and post-test were compared by Wilcoxon pair test and Mann Whitney U test. The level of significance was set at p <0.05. RESULTS: Twenty and 21 students participated in session I and II respectively, and all (100%) of them felt that the case scenarios made the subject more interesting, and 19 (90.5%) students felt more such sessions should be added and be used along with lectures. Post test score after case-based learning was significantly higher (For Oral Leukoplakia p=0.028, for Oral Squamous Cell Carcinoma p<0.001) in comparison to didactic lectures. CONCLUSIONS: As case-based learning was positively perceived and preferred along with lectures, an attempt to incorporate it along with lectures in clinically important topics should be made.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Mouth Neoplasms , Humans , Cross-Sectional Studies , Pathology, Oral , Squamous Cell Carcinoma of Head and Neck , Nepal , Students , Leukoplakia, Oral
3.
Ann Med Surg (Lond) ; 82: 104702, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36268452

ABSTRACT

Introduction and importance: Cutaneous Squamous cell carcinoma(cSCC) represents approximately 16% of scalp tumors. Overall, cSCC is significantly more common in the oropharyngeal mucosa than the skin. Smoking is a risk factor for mucosal lesions, risk factors for developing cutaneous SCC include age, ultraviolet light exposure, chronic scarring, history of ionizing radiation, androgenetic alopecia (in men), and immunosuppression. The rates of bone invasion in cutaneous SCC have not been well noted in the literature. Case report: We report a case of 57-year-old man with invasive squamous cell carcinoma of scalp with extension into bone, cortex and dura mater. Gross total removal of the tumor with extension of bony defect followed by repair of dura and repair of skin defect by VY advancement flap was done under general anaesthesia. At a 3-month follow-up, his wound is well healed. No evidence of metastasis is noted. Discussion: Cutaneous squamous cell carcinoma (cSCC) is the second most common non-melanoma skin cancer, and its incidence is steadily increasing. Although the majority of cSCCs are successfully eradicated by surgical excision, advanced cSCC poses a significant risk in terms of morbidity, impact on quality of life, and risk of death. Conclusions: Invasive cutaneous squamous cell carcinoma of scalp is a rare entity. Invasion to bone, cortex, and dura mater is furthermore rare. Therefore, proper management of advanced cSCC is of the utmost importance since local invasion, delayed diagnosis, and metastasis contribute to increased costs and morbidity. A multi-disciplinary team approach is recommended.

4.
Ann Med Surg (Lond) ; 80: 104232, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36045778

ABSTRACT

Introduction: Erdheim-Chester Disease (ECD) is a rare non-Langerhans cell histiocytosis with a propensity to involve multiple organs. Case presentation: We report a case of a patient in mid-60s with occipital headache and ataxia. Following the radiological and immunohistochemical investigations and genomic studies, a diagnosis of ECD was made with two intracerebral lesions. Brain lesions were resected and the patient was discharged with the medication Vemurafenib. After 3 years of diagnosis and 13 years of initial presentation, patient passed away. Discussion: ECD frequently presents with Diabetes Insipidus as initial presentation, long bone osteosclerosis as the most common presentation, and has multi-system predisposition. ECD can be differentiated from Langerhans Cell Histiocytosis (LCH) with immunohistochemistry images of the biopsy specimens. Further, with genomic analysis of ECD, the neoplastic nature has been highlighted and targeted therapies like Vemurafenib and Cobimetinib are shown to be effective. Conclusion: Good clinical judgement and supporting investigations can aid in diagnosing rare entities like ECD even in resource-limited settings.

6.
Int J Surg Case Rep ; 90: 106635, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34974353

ABSTRACT

INTRODUCTION AND IMPORTANCE: Ileosigmoid knotting is a surgical emergency. Common in Asian males, it is presented with signs and symptoms of diffuse peritonitis. Aggressive resuscitation with intravenous fluids and antibiotics followed by workup enable the patient hemodynamically stable. Explorative laparotomy followed by colo-colic anastomosis and double barrel ileostomy is curative. CASE PRESENTATION: A 32-year-old-male from Nepal with a chief complain of diffuse abdominal pain for a day and signs of peritonitis presented to Emergency room. After assessing and stabilizing the patient, explorative laparotomy was performed. Ileal and sigmoid resection followed by colo-colic anastomosis and double barrel ileostomy was done. On regular follow-up, he is in his usual state of health. DISCUSSION: The incidence of ileosigmoid knotting is reported to be about 1.6 cases per year. It is often misdiagnosed as non-specific intestinal obstruction which confers poor prognostic value to the patient. It should be identified promptly and intervened timely. CONCLUSION: Ileosigmoid knotting is a rare but dangerous differential of acute abdomen not to be missed. Early assessment and quick decision making is the key to provide excellent prognosis to the patient in need, provided adequate surgical skills are demonstrated.

7.
Article in English | MEDLINE | ID: mdl-34511344

ABSTRACT

OBJECTIVE: This review focused on comparing the anesthetic efficacy of intraosseous injection and conventional inferior alveolar nerve block in mandibular third molar surgery. STUDY DESIGN: Three electronic databases (PubMed, Scopus, and Web of Science) were accessed to identify randomized controlled trials comparing intraosseous injection with conventional inferior alveolar nerve block in mandibular third molar surgery. The outcome measures included onset of anesthesia, success of anesthetic technique, pain during injection of anesthesia, pain during surgery, and duration of anesthesia. RESULTS: Four studies met the inclusion criteria and consisted of 242 mandibular third molar surgeries. No significant differences were found between the anesthetic techniques in terms of onset of anesthesia, success of anesthetic technique, pain during injection of anesthesia, and pain during surgery. However, the intraosseous technique revealed a significantly shorter duration of anesthesia than the inferior alveolar nerve block (mean difference, -56.34 minutes; 95% confidence interval, -70.72 to -41.97; P < .001). CONCLUSIONS: Despite having anesthetic efficacy similar to that of the conventional inferior alveolar nerve block, intraosseous injection has an added benefit of early recovery of sensation owing to its shorter duration of anesthesia.


Subject(s)
Anesthesia, Dental , Nerve Block , Anesthesia, Dental/methods , Anesthetics, Local , Double-Blind Method , Humans , Lidocaine , Mandibular Nerve , Molar, Third/surgery
8.
J Nepal Health Res Counc ; 19(2): 259-263, 2021 Sep 06.
Article in English | MEDLINE | ID: mdl-34601513

ABSTRACT

BACKGROUND: An impacted tooth is a tooth which does not reach the occlusal plane even after two-thirds root formation. Conditions associated with impacted teeth include trismus, cystic lesions, and cervical caries of second molars. The objective of this study was to evaluate the occurrence of carious lesions in the distal aspect of the mandibular second molar and its association with the presence of mandibular third molars. METHODS: A cross-sectional study was conducted from September 2018 to September 2020. Approval was taken from the Institutional Review Committee with reference number 90/77/78. Orthopantomograms of patients aged 18 years or older were studied. Information on age, gender, mandibular second and third molars were recorded. Convenient sampling was done. Statistical analysis was done using Statistical Package for Social Sciences version 21. RESULTS: A total of 626 radiographs were studied of which mesioangular impaction (35.3%) was the most prominent type and followed by horizontal impaction, causing distal caries in second molars. The age group between 20-40 years and female gender had the higher prevalence of distal caries in second molar teeth. There was a significant correlation between gender and cavity existence (p=0.00), between impaction and existence of decay (p=0.00), and depth of impaction with cavity formation (p=0.004). CONCLUSIONS: A total of 31.8% of the patients with impacted mandibular third molars had distal cervical caries in second molars. Mesioangular type, female gender, type A were the prominent factors associated with distal caries in second molar teeth due to impacted third molars.


Subject(s)
Dental Caries , Tooth, Impacted , Adult , Cross-Sectional Studies , Dental Caries/epidemiology , Female , Humans , Molar, Third/diagnostic imaging , Nepal , Prevalence , Tooth, Impacted/diagnostic imaging , Tooth, Impacted/epidemiology , Young Adult
9.
Clin Case Rep ; 9(9): e04804, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34532050

ABSTRACT

Creutzfeldt-Jakob disease, though rare, should be considered in the clinical picture of rapidly progressive dementia and absence of verbal response as evident in our case despite the absence of typical radiological picture.

10.
Int J Surg Case Rep ; 85: 106189, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34280876

ABSTRACT

INTRODUCTION AND IMPORTANCE: Strangulation of penis, a surgical emergency, is often encountered in patients with psychiatric disorders and patients attempting to increase sexual arousal. Materials ranging from metallic to non-metallic like plastic bottles are used by the patients. The important factors to be considered for the successful treatment include the availability of instruments and the surgical skills of the doctor. CASE PRESENTATION: A 45 year-old man with a comorbidity of severe depression presented to Emergency with a two months long history of penile strangulation with a plastic bottle neck. The gross appearance of the penis showed edema and proliferative growths. He was intervened with a cable wire cutter as standard instrument failed to do so. The patient was discharged on the same day of intervention. However, he was lost to subsequent follow up. DISCUSSION: Penile strangulation which is common in people with mental disorders should be considered as a surgical emergency as it can present with devastating complications. No specific methods and tools have been recommended for the removal of those objects. The shame felt by patient is the root cause for late surgical consultation and are prone to develop complications. Simple instruments can be used for the intervention provided good surgical skills are demonstrated. CONCLUSION: Common in psychiatric patients who deny medical attention due to shame, penile strangulation should be intervened quickly and simple instruments not routinely used in surgical practice can be effectively used to remove the offending objects.

11.
J Exp Bot ; 72(14): 5208-5220, 2021 07 10.
Article in English | MEDLINE | ID: mdl-33989419

ABSTRACT

By responding to the variable soil environments in which they are grown, the roots of rice crops are likely to contribute to yield stability across a range of soil moistures, nutrient levels, and establishment methods. In this study, we explored different approaches to quantification of root plasticity and characterization of its relationship with yield stability. Using four different statistical approaches (plasticity index, slope, AMMI, and factor analytic) on a set of 17 genotypes including several recently-developed breeding lines targeted to dry direct-seeding, we identified only very few direct relationships between root plasticity and yield stability. However, genotypes identified as having combined yield stability and root plasticity showed higher grain yields across trials. Furthermore, root plasticity was expressed to a greater degree in puddled transplanted trials rather than under dry direct-seeding. Significant interactions between nitrogen and water resulted in contrasting relationships between nitrogen-use efficiency and biomass stability between puddled-transplanted and direct-seeded conditions. These results reflect the complex interaction between nitrogen, drought, and even different types of drought (as a result of the establishment method) on rice root growth, and suggest that although rice root plasticity may confer stable yield across a range of environments, it might be necessary to more narrowly define the targeted environments to which it will be most beneficial.


Subject(s)
Oryza , Droughts , Edible Grain , Oryza/genetics , Plant Breeding , Seeds
12.
Clin J Gastroenterol ; 14(2): 577-580, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33475969

ABSTRACT

Abdominal cocoon syndrome coexistent with military tuberculosis is a very rare entity, and its occurrence in a young adult male has not been previously reported. The disease in combination with military tuberculosis is associated with significant morbidity and mortality if underdiagnosed and untreated; hence, a high index of suspicion is required in a patient with tuberculosis presenting with intestinal pseudo-obstruction. The ideal treatment of the combination is surgical excision of cocoon along with oral anti-tubercular therapy (ATT), when the initial conservative management fails. However, surgery is frequently complicated by iatrogenic enterotomy due to the fibrinous cocoon. The best option in these cases may be a bail-out method of diverting jejunostomy. This helps relieve intestinal pseudo-obstruction and promotes early initiation of ATT as has been demonstrated in the present case.


Subject(s)
Intestinal Obstruction , Military Personnel , Tuberculosis , Conservative Treatment , Humans , Intestinal Obstruction/etiology , Intestinal Obstruction/surgery , Male , Tuberculosis/complications , Tuberculosis/diagnosis , Tuberculosis/drug therapy , Young Adult
13.
J Nepal Health Res Counc ; 19(3): 424-429, 2021 Dec 14.
Article in English | MEDLINE | ID: mdl-35140426

ABSTRACT

BACKGROUND: Neoplastic as well as non-neoplastic lesions commonly involve oral mucosa. It had been observed that benign lesions were more common than malignant ones. The present study was done to evaluate the pattern of distribution of various oral mucosal lesions in a tertiary care hospital. METHODS: This retrospective cross-sectional study reviewed the archival records in the Department of Pathology, Gandaki Medical College, Nepal from January 2017 to December 2020. The records of patients with histopathologic diagnosis of oral mucosal lesions were obtained. The histopathological diagnosis, age, gender, and the site of involvement were collected using a prepared form. Descriptive statistics was applied using SPSS 20 software. RESULTS: Oral mucosal lesions included 3.7% (180 out of total 4895) of cases diagnosed histopathologically. The cases were common among females (101cases/56.1%). Most of the oral mucosal lesions were diagnosed in more than 45 years old patients (75cases/41.7%). The non-neoplastic oral lesions (106cases/58.9%) were the most common lesions followed by neoplastic oral lesions (52cases/28.9%). Among non-neoplastic oral lesions, reactive hyperplastic oral lesions were the most common (50cases/27.8%). Reactive hyperplastic oral lesions frequently affected gingiva (18cases/36%). Neoplastic lesions (Benign neoplasm: 12cases/44.4%; Malignant lesions; 10cases/40%) frequently affected the tongue. CONCLUSIONS: Oral lesions were mostly non-neoplastic and reactive hyperplasia being the most commonest presentation Keywords: Neoplastic; non-neoplastic; oral mucosal lesions; reactive.


Subject(s)
Retrospective Studies , Cross-Sectional Studies , Female , Humans , Hyperplasia , Middle Aged , Nepal/epidemiology , Tertiary Care Centers
14.
Dent Traumatol ; 37(2): 314-320, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33190403

ABSTRACT

INTRODUCTION: The retromandibular transparotid approach provides the shortest and the most direct access to mandibular sub-condylar fractures. However, this approach is less preferred due to the fear of facial nerve injury. The aim of this study was to evaluate the safety and morbidity of the retromandibular transparotid approach for open reduction and internal fixation of sub-condylar mandibular fractures. METHODS: A retrospective cohort study of 29 patients with 35 sub-condylar mandibular fractures who underwent open reduction and internal fixation through the retromandibular transparotid approach was conducted. The primary study variable was facial nerve palsy, whereas the secondary variables were infection, sialocele, salivary fistula, stability of the fractured segments, post-operative malocclusion, Frey's syndrome, and unesthetic scar. All patients were followed up for 6 months. Predictor variables included age, gender, side, location, displacement, etiology, concomitant maxillofacial fractures, and healing status. Fisher's exact test was calculated to find the association between primary variables and predictor variables. RESULT: Out of 35 sub-condylar fractures (29 patients; 23 male, 6 female), four (11.42%) developed transient facial nerve palsy. Fractures at the condylar neck level (P = .045) and with displacement (P = .026) were significantly associated with the development of facial nerve palsy. Four patients (13.8%) developed slight malocclusion, two had surgical site infections, two developed sialoceles, and one had a salivary fistula. CONCLUSION: The retromandibular transparotid approach is safe and effective with rare major complications in the management of sub-condylar fractures of the mandible. Condylar neck fractures and displaced fractured segments are associated with an increased risk of development of facial nerve palsy.


Subject(s)
Facial Nerve Injuries , Mandibular Fractures , Female , Fracture Fixation, Internal , Humans , Male , Mandible , Mandibular Condyle , Mandibular Fractures/diagnostic imaging , Mandibular Fractures/surgery , Retrospective Studies , Treatment Outcome
15.
J Nepal Health Res Counc ; 18(1): 70-74, 2020 Apr 20.
Article in English | MEDLINE | ID: mdl-32335596

ABSTRACT

BACKGROUND: Oral biopsy procedures are rarely practiced by dental surgeons around the world though they should be able to perform the biopsies for the diagnosis of oral lesions. Our objective was to access the knowledge, attitude and practice of oral biopsy procedures among the dental surgeons who are members of Nepal Dental Association. METHODS: A cross sectional study was conducted from December 2018 to March 2019, among the dental surgeons who were registered in Nepal Dental Association till September 2018. A standard pretested questionnaire was prepared using Google forms, was emailed to 374 dental surgeons. Two reminder emails were sent at an interval of 1 month. The non-responding dental surgeons who were reachable through mobile number (N=274) were contacted after the third 3rd email. Out of 274, 10 dental surgeons had completed postgraduation, so 264 of them were included in the study. A reminder call was made after one week. The data was entered in SPSS version 20 software and analyzed using descriptive statistics. RESULTS: There were 160 responses to the emails after the conversation through mobile phone. The response rate was 60.6% with the predominance of female responders (66.9%). Though the majority of dental surgeons (96.2%) had encountered one or the other lesions requiring biopsy, only few of them (7.5%) had performed the biopsy which was mainly due to lack experience and skill (75.6%). CONCLUSIONS: Most of the dental surgeon are not comfortable performing biopsy with majority seem to lack expereice and skill. There is need to organize training to Dental Surgeons to enhance their practical skills.


Subject(s)
Biopsy/methods , Health Knowledge, Attitudes, Practice , Oral and Maxillofacial Surgeons/psychology , Adult , Cross-Sectional Studies , Female , Humans , Male , Nepal , Surveys and Questionnaires
16.
BMC Genomics ; 20(1): 471, 2019 Jun 10.
Article in English | MEDLINE | ID: mdl-31182016

ABSTRACT

BACKGROUND: Puddled transplanted system of rice cultivation despite having several benefits, is a highly labor, water and energy intensive system. In the face of changing climatic conditions, a successful transition from puddled to dry direct seeded rice (DDSR) cultivation system looks must in future. Genome-wide association study was performed for traits including, roots and nutrient uptake (14 traits), plant-morphological (5 traits), lodging-resistance (4 traits) and yield and yield attributing traits (7 traits) with the aim to identify significant marker-trait associations (MTAs) for traits enhancing rice adaptability to dry direct-seeded rice (DDSR) system. RESULTS: Study identified a total of 37 highly significant MTAs for 20 traits. The false discovery rate (FDR) ranged from 0.264 to 3.69 × 10- 4, 0.0330 to 1.25 × 10- 4, and 0.0534 to 4.60 × 10- 6 in 2015WS, 2016DS and combined analysis, respectively. The percent phenotypic variance (PV) explained by SNPs ranged from 9 to 92%. Among the identified significant MTAs, 15 MTAs associated with the traits including nodal root, root hair length, root length density, stem and culm diameter, plant height and grain yield were reported to be located in the proximity of earlier identified candidate gene. The significant positive correlation of grain-yield with seedling establishment traits, root morphological and nutrient-uptake related traits and grain yield attributing traits pointing towards combining target traits to increase rice yield and adaptability under DDSR. Seven promising progenies with better root morphology, nutrient-uptake and higher grain yield were identified that can further be used in genomics assisted breeding for DDSR varietal development. CONCLUSIONS: Once validated, the identified MTAs and the SNPs linked with trait of interest could be of direct use in genomic assisted breeding (GAB) to improve grain yield and adaptability of rice under DDSR.


Subject(s)
Oryza/genetics , Adaptation, Physiological , Genetic Markers , Genome-Wide Association Study , Genomics , Linkage Disequilibrium , Oryza/anatomy & histology , Phenotype , Seedlings
17.
Sci Rep ; 9(1): 9334, 2019 06 27.
Article in English | MEDLINE | ID: mdl-31249338

ABSTRACT

In the face of global water scarcity, a successful transition of rice cultivation from puddled to dry direct-seeded rice (DDSR) is a future need. A genome-wide association study was performed on a complex mapping population for 39 traits: 9 seedling-establishment traits, 14 root and nutrient-uptake traits, 5 plant morphological traits, 4 lodging resistance traits, and 7 yield and yield-contributing traits. A total of 10 significant marker-trait associations (MTAs) were found along with 25 QTLs associated with 25 traits. The percent phenotypic variance explained by SNPs ranged from 8% to 84%. Grain yield was found to be significantly and positively correlated with seedling-establishment traits, root morphological traits, nutrient uptake-related traits, and grain yield-contributing traits. The genomic colocation of different root morphological traits, nutrient uptake-related traits, and grain-yield-contributing traits further supports the role of root morphological traits in improving nutrient uptake and grain yield under DDSR. The QTLs/candidate genes underlying the significant MTAs were identified. The identified promising progenies carrying these QTLs may serve as potential donors to be exploited in genomics-assisted breeding programs for improving grain yield and adaptability under DDSR.


Subject(s)
Edible Grain , Nutrients/metabolism , Oryza/physiology , Plant Development/genetics , Plant Roots/anatomy & histology , Plant Roots/genetics , Quantitative Trait, Heritable , Biological Variation, Population , Chromosome Mapping , Cluster Analysis , Genetic Association Studies , Genetics, Population , Genome-Wide Association Study , Linkage Disequilibrium , Phenotype , Plant Breeding , Polymorphism, Single Nucleotide , Quantitative Trait Loci , Seedlings , Seeds
18.
Front Plant Sci ; 8: 1879, 2017.
Article in English | MEDLINE | ID: mdl-29163604

ABSTRACT

Reducing water requirements and lowering environmental footprints require attention to minimize risks to food security. The present study was conducted with the aim to identify appropriate root traits enhancing rice grain yield under alternate wetting and drying conditions (AWD) and identify stable, high-yielding genotypes better suited to the AWD across variable ecosystems. Advanced breeding lines, popular rice varieties and drought-tolerant lines were evaluated in a series of 23 experiments conducted in the Philippines, India, Bangladesh, Nepal and Cambodia in 2015 and 2016. A large variation in grain yield under AWD conditions enabled the selection of high-yielding and stable genotypes across locations, seasons and years. Water savings of 5.7-23.4% were achieved without significant yield penalty across different ecosystems. The mean grain yield of genotypes across locations ranged from 3.5 to 5.6 t/ha and the mean environment grain yields ranged from 3.7 (Cambodia) to 6.6 (India) t/ha. The best-fitting Finlay-Wilkinson regression model identified eight stable genotypes with mean grain yield of more than 5.0 t/ha across locations. Multidimensional preference analysis represented the strong association of root traits (nodal root number, root dry weight at 22 and 30 days after transplanting) with grain yield. The genotype IR14L253 outperformed in terms of root traits and high mean grain yield across seasons and six locations. The 1.0 t/ha yield advantage of IR14L253 over the popular cultivar IR64 under AWD shall encourage farmers to cultivate IR14L253 and also adopt AWD. The results suggest an important role of root architectural traits in term of more number of nodal roots and root dry weight at 10-20 cm depth on 22-30 days after transplanting (DAT) in providing yield stability and preventing yield reduction under AWD compared to continuous flooded conditions. Genotypes possessing increased number of nodal roots provided higher yield over IR64 as well as no yield reduction under AWD compared to flooded irrigation. The identification of appropriate root architecture traits at specific depth and specific growth stage shall help breeding programs develop better rice varieties for AWD conditions.

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