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The production and productivity of rice has been challenged due to biotic and abiotic factors. Bacterial blight (BB) disease, caused by Xanthomonas oryzae pv. oryzae, is one of the important biotic stress factors, which reduces rice production by 20%–50%. The deployment of host plant resistance is the most preferred strategy for management of BB disease, and breeding disease resistant varieties remains a very economical and effective option. However, it is difficult to develop rice varieties with durable broad-spectrum resistance against BB using conventional approaches alone. Modern biotechnological tools, particularly the deployment of molecular markers, have facilitated the cloning, characterization and introgression of BB resistance genes into elite varieties. At least 46 BB resistance genes have been identified and mapped from diverse sources till date. Among these, 11 genes have been cloned and characterized. Marker-assisted breeding remains the most efficient approach to improve BB resistance by introducing two or more resistance genes into target varieties. Among the identified genes, xa5, xa13 and Xa21 are being widely used in marker-assisted breeding and more than 70 rice varieties or hybrid rice parental lines have been improved for their BB resistance alone or in combination with genes/QTLs conferring tolerance to other stress. We review the developments related to identification and utilization of various resistance genes to develop BB resistant rice varieties through marker-assisted breeding.

Crop yield varies considerably within agroecology depending on the genetic potential of crop cultivars and various edaphic and climatic variables. Understanding site-specific changes in crop yield and genotype × environment interaction are crucial and needs exceptional consideration in strategic breeding programs. Further, genotypic response to diverse agro-ecologies offers identification of strategic locations for evaluating traits of interest to strengthen and accelerate the national variety release program. In this study, multi-location field trial data have been used to investigate the impact of environmental conditions on crop phenological dynamics and their influence on the yield of mungbean in different agroecological regions of the Indian subcontinent. The present attempt is also intended to identify the strategic location(s) favoring higher yield and distinctiveness within mungbean genotypes. In the field trial, a total of 34 different mungbean genotypes were grown in 39 locations covering the north hill zone (n = 4), northeastern plain zone (n = 6), northwestern plain zone (n = 7), central zone (n = 11) and south zone (n = 11). The results revealed that the effect of the environment was prominent on both the phenological dynamics and productivity of the mungbean. Noticeable variations (expressed as coefficient of variation) were observed for the parameters of days to 50% flowering (13%), days to maturity (12%), reproductive period (21%), grain yield (33%), and 1000-grain weight (14%) across the environments. The genotype, environment, and genotype × environment accounted for 3.0, 54.2, and 29.7% of the total variation in mungbean yield, respectively (p < 0.001), suggesting an oversized significance of site-specific responses of the genotypes. Results demonstrated that a lower ambient temperature extended both flowering time and the crop period. Linear mixed model results revealed that the changes in phenological events (days to 50 % flowering, days to maturity, and reproductive period) with response to contrasting environments had no direct influence on crop yields (p > 0.05) for all the genotypes except PM 14-11. Results revealed that the south zone environment initiated early flowering and an extended reproductive period, thus sustaining yield with good seed size. While in low rainfall areas viz., Sriganganagar, New Delhi, Durgapura, and Sagar, the yield was comparatively low irrespective of genotypes. Correlation results and PCA indicated that rainfall during the crop season and relative humidity significantly and positively influenced grain yield. Hence, the present study suggests that the yield potential of mungbean is independent of crop phenological dynamics; rather, climatic variables like rainfall and relative humidity have considerable influence on yield. Further, HA-GGE biplot analysis identified Sagar, New Delhi, Sriganganagar, Durgapura, Warangal, Srinagar, Kanpur, and Mohanpur as the ideal testing environments, which demonstrated high efficiency in the selection of new genotypes with wider adaptability.

Forty five rabi sorghum land races were evaluated along with three checks M35-1, CSV 22R and Phule Chitra for three years (2011-2013) at ARS, Tandur to identify promising and stable donors for yield and related traits to be used in crossing programmes. Analysis of variance of pooled data over three years indicated significant differences among the genotypes and environments for days to 50% flowering, days to maturity, plant height, test weight, grain yield and fodder yield. Significant GxE interaction was observed for the six traits indicating differential response of the genotypes to different seasons. Environmental indices revealed early expression of flowering and early crop maturity in 2012 and 2013 respectively. The expression of plant height was good in 2013 and test weight, grain and fodder yields in the year 2011. This study identified that the land races Jamkhed local1 and RSV 1460 for breeding early duration types, RSV 1425 for improving the test weight, RS 1449 and Pusegaon local for grain yield improvement, Dharampur local, Nimbodi local, SSRG 170, SSRG 204, SSRG 203 and SSRG 236 for forage sorghum improvement are suitable.

The present study was carried out to study the genetic divergence among 75 germplasm lines of safflower. Analysis ofvariance revealed significant variation among the genotypes for all the characters studied. Among the genotypes, GMU 3327,GMU 3279, GMU 3325 and GMU 3313 were found to be promising on the basis of per se performance for seed yield. Seedyield exhibited maximum contribution towards genetic divergence followed by number of capitula per plant, number of seedsper capitulum, oil content, days to 50% flowering and days to maturity. The genotypes were grouped into 8 clusters out ofwhich cluster II is having maximum of 23 genotypes followed by cluster I with 20 genotypes. Maximum inter cluster distancewas observed between clusters VII and VIII followed by clusters VI and VIII, clusters IV and VIII and clusters I and VIII .

Rice is a highly consumed staple cereal cultivated predominantly in Asian countries, which share 90% of global rice production. Rice is a primary calorie provider for more than 3.5 billion people across the world. Preference and consumption of polished rice have increased manifold, which resulted in the loss of inherent nutrition. The prevalence of micronutrient deficiencies (Zn and Fe) are major human health challenges in the 21st century. Biofortification of staples is a sustainable approach to alleviating malnutrition. Globally, significant progress has been made in rice for enhancing grain Zn, Fe, and protein. To date, 37 biofortified Fe, Zn, Protein and Provitamin A rich rice varieties are available for commercial cultivation (16 from India and 21 from the rest of theworld; Fe > 10 mg/kg, Zn > 24mg/kg, protein > 10% in polished rice as India target while Zn > 28 mg/kg in polished rice as international target). However, understanding the micronutrient genetics, mechanisms of uptake, translocation, and bioavailability are the prime areas that need to be strengthened. The successful development of these lines through integratedgenomic technologies can accelerate deployment and scaling in future breeding programs to address the key challenges of malnutrition and hidden hunger. [ABSTRACT FROM AUTHOR]

Ninety safflower genotypes representing diverse geographic regions were studied for genetic divergence using Mahalanobis D2 static. The genotypes were grouped into 12 clusters. Seed yield contributed maximum to the total divergence. The maximum inter cluster distance was observed between cluster VIII and cluster XI whereas minimum distance between the clusters IV and XII. The accession 41 is the distinct one which can be highly utilized in further breeding programme. Selection of the genotypes from these clusters for hybridization programme may result in good recombinants. [ABSTRACT FROM AUTHOR]

Genetic analysis for grain and fodder yield in sorghum genotypes using six generation means indicated the major role of additive genetic effects (d) for days to maturity and grain yield in both the crosses viz., EP 82 x CRS 1 and CSV 14R x SPV 1375. The cross EP 82 x CRS 1 indicated additive variance for plant height and grain yield while the cross CSV 14 R x SPV 1375 for days to maturity, plant height, panicle length, test weight and grain yield. Among the epistatic components of genetic variance, the fixable additive x additive component (i) was significant for almost all the traits except, days to 50% flowering in the cross EP 82 x CRS 1 and fodder yield in the cross CSV 14 R x SPV 1375. The characters exhibiting significant and positive additive genetic effects invariably were accompanied by additive x additive (i) interaction effects for plant height in the cross EP 82 x CRS1. However, the presence of positive and significant additive x additive interactions along with additive genetic effects for test weight in the cross EP 82 x CRS1 indicate the predominance of interaction component rather than their direct influence. Additive as well as additive x additive interaction effects with duplicate epistasis were observed in the cross EP 82 x CRS1 for plant height. Grain yield exhibited significant dominance variance in the cross CSV 14R x SPV 1375. Fodder yield exhibited significant dominance and dominance x dominance interactions in the cross CSV 14R x SPV 1375 [ABSTRACT FROM AUTHOR]

In the present investigation, sufficient variability was observed in the drought tolerant pigeonpea genotypes for the traits under study. Most of theyield contributing characters showed significant positive correlation whereas, number of primary branches per plant showed significant negativecorrelation with seed yield. Days to maturity had maximum direct effect on seed yield followed by number of pods per plant and plant height andnumber of secondary branches which had negative direct effect on seed yield. Number of secondary branches per plant, number of pods per plantand days to maturity were identified as important yield components and hence, selection should be focused on these traits to improve yield indrought tolerant genotypes of pigeonpea.

Background: Effective management of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) requires large-scale testing to identify and isolate infectious carriers. Self-administered buccal swab and saliva collection are convenient, painless, and safe alternatives to the current healthcare worker (HCW)-collected nasopharyngeal swab (NPS)., Methods: A cross-sectional single-centre study was conducted on 42 participants who had tested positive for SARS-CoV-2 via an NPS within the past 7 days. Real-time polymerase chain reaction (RT-PCR) was performed and cycle threshold (Ct) values were obtained for each test. The positive percent agreement (PPA), negative percent agreement (NPA), and overall agreement (OA) were calculated for the saliva samples and buccal swabs, and compared with NPS., Results: Among the 42 participants, 73.8% (31/42) tested positive by any one of the three tests. With reference to NPS, the saliva test had PPA 66.7%, NPA 91.7%, and OA 69.0%; the buccal swab had PPA 56.7%, NPA 100%, and OA 73.8%., Conclusion: Self-collected saliva tests and buccal swabs showed only moderate agreement with HCW-collected NPS. Primary screening for SARS-CoV-2 may be performed with a saliva test or buccal swab, with a negative test warranting a confirmatory NPS to avoid false-negatives, minimize discomfort, and reduce the risk of spread to the community and HCWs., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Rescue cervical cerclage (RCC), also known as emergency cerclage, has long been the subject of controversy. Its use in women who have a dilated cervix has been ambivalent. RCC is often considered as a salvage measure for pregnancies which are at a high risk of severe preterm delivery (PTD) or mid-trimester miscarriage. This study aims to examine and assess the efficacy of RCC and its ability to prolong pregnancy until neonatal viability is achieved. The current data suggest that RCC is associated with a longer latency period frequently resulting in better pregnancy outcomes (Namouz S, Porat S, Okun N, Windrim R, Farine D. Emergency cerclage: literature review. Obstet Gynecol Surv. 2013;68:379-88). This is supported by the Royal College of Obstetricians and Gynaecologists (RCOG) which states that the insertion of a rescue cerclage may delay delivery by a further 5 weeks on average as compared with expectant management or bed rest alone (Shennan AH. To MS: RCOG Green Top Guidelines: Cervical Cerclage RCOG.2011. Available from: www.rcog.org.uk). It further states that it may be associated with a two-fold reduction in the possibility of delivery before 34 weeks of gestation (Shennan AH. To MS: RCOG Green Top Guidelines: Cervical Cerclage RCOG.2011. Available from: www.rcog.org.uk). Our study reveals that the average insertion to delivery interval at our centre was 71.2 days with a live birth rate of 92.5%. A total of 89.1% of women delivered beyond 24 weeks of gestation.

Histone lysine methylation by histone lysine methyltransferases (HKMTs) has been implicated in regulation of gene expression. While significant progress has been made to understand the roles and mechanisms of animal HKMT functions, only a few plant HKMTs are functionally characterized. To unravel histone substrate specificity, degree of methylation and catalytic activity, we analyzed Arabidopsis Trithorax-like protein (ATX), Su(var)3-9 homologs protein (SUVH), Su(var)3-9 related protein (SUVR), ATXR5, ATXR6, and E(Z) HKMTs of Arabidopsis, maize and rice through sequence and structure comparison. We show that ATXs may exhibit methyltransferase specificity toward histone 3 lysine 4 (H3K4) and might catalyse the trimethylation. Our analyses also indicate that most SUVH proteins of Arabidopsis may bind histone H3 lysine 9 (H3K9). We also predict that SUVH7, SUVH8, SUVR1, SUVR3, ZmSET20 and ZmSET22 catalyse monomethylation or dimethylation of H3K9. Except for SDG728, which may trimethylate H3K9, all SUVH paralogs in rice may catalyse monomethylation or dimethylation. ZmSET11, ZmSET31, SDG713, SDG715, and SDG726 proteins are predicted to be catalytically inactive because of an incomplete S-adenosylmethionine (SAM) binding pocket and a post-SET domain. E(Z) homologs can trimethylate H3K27 substrate, which is similar to the Enhancer of Zeste homolog 2 of humans. Our comparative sequence analyses reveal that ATXR5 and ATXR6 lack motifs/domains required for protein-protein interaction and polycomb repressive complex 2 complex formation. We propose that subtle variations of key residues at substrate or SAM binding pocket, around the catalytic pocket, or presence of pre-SET and post-SET domains in HKMTs of the aforementioned plant species lead to variations in class-specific HKMT functions and further determine their substrate specificity, the degree of methylation and catalytic activity., (© 2017 Wiley Periodicals, Inc.)