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The development of nutrient-use efficient rice lines is a priority amidst the changing climate and depleting resources viz., water, land, and labor for achieving sustainability in rice cultivation. Along with the traditional transplanted irrigated system of cultivation, the dry direct-seeded aerobic system is gaining ground nationwide. The root-related traits play a crucial role in nutrient acquisition, adaptation and need to be concentrated along with the yield-attributing traits. We phenotyped an association panel of 118 rice lines for seedling vigour index (SVI) traits at 14 and 21 days after sowing (DAS), root-related traits at panicle initiation (PI) stage in polythene bags under controlled aerobic condition, yield and yield-related traits under the irrigated condition at ICARIIRR, Hyderabad, Telangana; irrigated and aerobic conditions at ARS, Dhadesugur, Raichur, Karnataka. The panel was genotyped using simple sequence repeats (SSR) markers and genome-wide association studies were conducted for identifying marker-trait associations (MTAs). Significant correlations were recorded for root length, root dry weight with SVI, root volume at the PI stage, number of productive tillers per plant, spikelet fertility, the total number of grains per panicle with grain yield per plant under irrigated conditions, and the total number of grains per panicle with grain yield per plant under aerobic condition. The panel was divided into three sub-groups (K = 3) and correlated with the principal component analysis. The maximum number of MTAs were found on chromosomes 2, 3, and 12 with considerable phenotypic variability. Consistent MTAs were recorded for SVI traits at 14 and 21 DAS (RM25310, RM80, RM22961, RM1385), yield traits under irrigated conditions (RM2584, RM5179, RM410, RM20698, RM14753) across years at ICAR-IIRR, grain yield per plant (RM22961, RM1146) under the aerobic condition, grain yield per plant at irrigated ICAR-IIRR and SVI (RM5501), root traits at PI stage (RM2584, RM80, RM410, RM1146, RM18472). Functionally relevant genes near the MTAs through in-silico expression analysis in root and panicle tissues viz., HBF2 bZIP transcription factor, WD40 repeat-like domain, OsPILS6a auxin efflux carrier, WRKY108, OsSCP42, OsMADS80, nodulin-like domain-containing protein, amino acid transporter using various rice expression databases were identified. The identified MTAs and rice lines having high SVI traits (Langphou, TI-128, Mouli, TI-124, JBB-631-1), high yield under aerobic (Phouren, NPK-43, JBB-684, Ratnamudi, TI-112), irrigated conditions (KR-209, KR-262, Phouren, Keibi-Phou, TI-17), robust root traits like root length (MoirangPhou-Angouba, Wangoo-Phou, JBB-661, Dissi, NPK-45), root volume (Ratnachudi, KJ-221, Mow, Heimang-Phou, PUP-229) can be further employed in breeding programs for the targeted environments aimed at improving seedling vigour, yield-related traits under irrigated condition, aerobic condition as adaptability to water-saving technology. [ABSTRACT FROM AUTHOR]

Wild introgressions play a crucial role in crop improvement by transferring important novel alleles and broadening allelic diversity of cultivated germplasm. In this study, two stable backcross alien introgression lines 166s and 14s derived from Swarn/ Oryza nivara IRGC81848 were used as parents to generate populations to map quantitative trait loci (QTLs) for yield-related traits. Field evaluation of yield-related traits in F2, F3, and F4 population was carried out in normal irrigated conditions during the wet season of 2015 and dry seasons of 2016 and 2018, respectively. Plant height, tiller number, productive tiller number, total dry matter, and harvest index showed a highly significant association to single plant yield in F2, F3, and F4. In all, 21, 30, and 17 QTLs were identified in F2, F2:3, and F2:4, respectively, for yield-related traits. QTLs qPH6.1 with 12.54% phenotypic variance (PV) in F2, qPH1.1 with 13.01% PV, qTN6.1 with 10.08% PV in F2:3, and qTGW6.1 with 15.19% PV in F2:4 were identified as major effect QTLs. QTLs qSPY4.1 and qSPY6.1 were detected for grain yield in F2 and F2:3 with PV 8.5 and 6.7%, respectively. The trait enhancing alleles of QTLs qSPY4.1 , qSPY6.1, qPH1.1 , qTGW6.1 , qTGW8.1, qGN4.1 , and qTDM5.1 were from O. nivara. QTLs of the yield contributing traits were found clustered in the same chromosomal region. qTGW8.1 was identified in a 2.6 Mb region between RM3480 and RM3452 in all three generations with PV 6.1 to 9.8%. This stable and consistent qTGW8.1 allele from O. nivara can be fine mapped for identification of causal genes. From this population, lines C212, C2124, C2128, and C2143 were identified with significantly higher SPY and C2103, C2116, and C2117 had consistently higher thousand-grain weight values than both the parents and Swarna across the generations and are useful in gene discovery for target traits and further crop improvement. [ABSTRACT FROM AUTHOR]

Background: Diabetic macular edema (DME) is the most common cause of vision loss in diabetic patients. As India has the second largest population of diabetic patients worldwide, availability of various treatment options for DME is essential. This postmarketing surveillance study was conducted to fulfill a commitment to the Regulatory Authority of India to examine the safety of dexamethasone intravitreal (DEX) implant over 1 year in Indian patients with DME receiving ≥1 DEX implant for DME-related visual impairment in clinical practice.Methods: This observational, prospective, non-interventional study enrolled patients aged ≥18 years scheduled to receive DEX implant for DME-related visual impairment. Baseline demographics, medical history, date of last DEX implant injection, detailed information about adverse events (AEs), AEs of special interest (AESIs), serious AEs (SAEs), and adverse drug reactions (ADRs) reported during postinjection visits and investigator telephone calls were collected. Primary outcome measures were treatment-emergent AE (TEAE), AESI, SAE, and ADR occurrences.Results: Of the enrolled patients (19 sites throughout India; n = 250), 84 had received DEX implant previously; mean (standard deviation; SD) duration between prior and study entry dose was 199.4 (156.0) days, and 91 (36.4%) had ≥1 prior ophthalmic condition. Over a mean of 182.6 (88.6) follow-up days (min-max: 0-364 days), 22 TEAEs were reported by 7 (2.8%) patients, 6 of whom had previously received DEX. AESIs of increased IOP (n = 3, 6 events) and glaucoma (n = 1, 1 event) were considered non-serious, of mild/moderate severity, and related to DEX treatment. Eyelid ptosis was reported in 1 patient (1 event). Nonocular AEs included cardiac AEs (n = 3, 4 events), pyrexia (n = 1, 2 events), and dyspnea (n = 1, 2 events). Three (1.2%) patients had 12 serious AEs; most were cardiac disorders; all were unrelated to DEX treatment. Two (0.8%) deaths were considered unrelated to treatment.Conclusions: Based on voluntary reporting of adverse events in this surveillance study, DEX implant for treatment of DME-related visual impairment in the Indian population demonstrated a favorable safety profile with few treatment-related TEAEs (none were considered serious) during the 1-year follow-up. These data supplement previous findings and confirm the safety of DEX implant in this population during usual clinical practice.Trial Registration: World Health Organization Clinical Trials Registry: CTRI/2017/04/008396 . Registered 24 April 2017. [ABSTRACT FROM AUTHOR]