Influence of biostimulants on growth and productivity of foxtail millet (Setaria italica L.) genotypes

A field experiment was carried out at AHRS, Bavikere, Karnataka during late kharif season of 2021to find out the “Influence of biostimulants on growth and productivity of foxtail millet (Setaria italica L.) genotypes’’. The field trial was laid out in split plot design with 12 treatment combinations. The study involves three genotypes in the main plot viz., SiA-3156 (G1), HMT-100-1 (G2) and DHFt-109-3 (G3). Foliar application of biostimulants in sub plots viz., 0.1 % humic acid (F1), 3 % panchagavya (F2), 0.1 % humic acid and 3 %panchagavya (F3) at 30 and 60 days after sowing (DAS) and recommended dose of fertilizer (RDF) as control (F4). Genotypes and Foliar application of biostimulants exhibited significant variation in growth and yield components of foxtail millet. Among the different genotypes, HMT-100-1 recorded significantly higher plant height (142.00 cm), number of tillers per meter (81.87) and leaf area (18.40 dm2/plant) at harvest and also yield components like panicle length (16.60 cm), grain weight per panicle (4.02 g) and grain yield (1701.0 kg/ha) compared to DHFt-109-3 and SiA -3156. In biostimulants, Foliar application of 0.1 % humic acid and 3 % panchagavya recorded significantly higher plant height (142.32 cm), number of tillers per metre (83.75) and leaf area (18.51 dm2/plant) at harvest and also yield components like panicle length (16.99 cm), grain weight per panicle (4.33 g) and grain yield (1781.2 kg/ha). While, they were found to be at their lowest with application of RDF alone. Interaction between genotypes and biostimulants was also found to be significant in which combination of HMT-100-1 with foliar application of 0.1 % humic acid and 3 %panchagavya recorded significantly higher growth and yield compared to other treatment combinations

Spectrum of chlorophyll mutations and morphological variations in Abelmoschus esculentus L. induced through gamma radiation

Okra [Abelmoschus esculentus (L.) Moench], is an economically exploited important traditional vegetable crop of the world. The present investigation examined the variability in induced chlorophyll mutants and othermorphological variations in okra. Seeds of two open pollinated popular varieties of okra namely Arka Anamika and Arka Abhay were irradiated with gamma doses of 30, 50 and 80 kR. The treatment 50 kR enhanced plant height, number of fruits per plant, fruit length, single fruit weight and total fruit yield per plant. Spectrum of several chlorophyll mutants were observed in the M1 generation. Other macro-mutants such as early and late flowering types, dwarf statured plants, leaf and flower mutants were also noticed at different doses of gamma radiation. The total number of visible mutation followed a trend of increasing frequency with the increase in dose of radiation

Generation Mean Analysis Reveals the Predominant Gene Effects for Grain Iron and Zinc Contents in Pearl Millet

Pearl millet [Pennisetum glaucum (L.) R. Br.] is a climate-resilient dryland cereal that has been identified as a potential staple food crop that can contribute to alleviating micronutrient malnutrition, particularly with respect to grain iron (Fe) and zinc (Zn) contents, in Sub-Saharan Africa and India. In this regard, an understanding of the inheritance pattern of genes involved in Fe and Zn contents is vital for devising appropriate breeding methods to genetically enhance their levels in grains. In this study, we aimed to determine the genetic effects underlying such inheritance and their interactions based on the generation mean analyses. Four experimental crosses and their six generations (P1, P2, F1, BCP1, BCP2, and F2) were independently evaluated in a compact family block design in 2017 rainy and 2018 summer seasons. ANOVA revealed highly significant mean squares (p < 0.01) among different generations for grain Fe and Zn contents. Six-parameter generation mean analyses revealed a predominance of additive genetic effect and a significant (p < 0.05) additive x dominant interaction for the grain Fe content. The additive genetic effect for the grain Zn content was also highly significant (p < 0.01). However, interaction effects contributed minimally with respect to most of the crosses for the grain Zn content and hence we assume that a simple digenic inheritance pattern holds true for it. Furthermore, we established that narrow-sense heritability was high for the grain Fe content (>61.78%), whereas it was low to moderate for the grain Zn content (30.60–59.04%). The lack of superior parent heterosis coupled with non-significant inbreeding depression for Fe and Zn contents in grains further confirmed the predominance of an additive genetic effect. These findings will contribute to strategizing a comprehensive breeding method to exploit the available variability of grain Fe and Zn contents for the development of biofortified hybrids of pearl millet

Studies on Genetic Variability and Associations of Fruit and Shoot Borer Infestation for Yield Attributing Traits in Transgressive Segregating Populations of Brinjal (Solanum melongena L.)

In the F2 generation of eggplants, resulting from the crosses between Bilichandubadane and Mullubadane in the F1 generation, a considerable level of variability was observed. These eggplant varieties, cultivated in an augmented design at ZARS Shimogga during the Kharif season of 2017, display numerous significant plant breeding characteristics and hold great potential for further improvement under varying growing conditions. The F2 investigation unveiled substantial diversity in nine quantitative traits. The strong correlation between the Genetic Coefficient of Variation (GCV) and Phenotypic Coefficient of Variation (PCV) values suggests that environmental factors have a relatively minor influence on the expression of these studied traits. Importantly, characteristics such as the number of fruits per plant, the number of primary branches, and the number of flowers per plant exhibited a substantial genetic contribution, as indicated by their high GCV and PCV values, in addition to significant broad sense heritability and genetic advancement. This implies that these traits are mainly governed by additive genes and can be effectively enhanced through selection without necessitating progeny testing. Furthermore, the high heritability values observed for most traits indicate considerable potential for improving yield and its components through selective breeding. Differences in mean values among the parent plants in various characteristics suggest the involvement of diverse parent plants in the crosses studied. Additionally, the F2 plants displayed superior performance in most traits compared to either of the parent plants, which can be attributed to the phenomenon of transgressive segregation

Correction to: Marker-assisted identification of novel genetic lines for salinity tolerance and their categorization for utilization in development of hybrid rice (Oryza sativa L.)

Identification of new sources of salinity-tolerant genotypes is prerequisite for rice breeding programs in different saline ecosystems. In the present experiment, we characterized 177 landraces from the Western Ghats of Karnataka under natural saline field conditions for two years using morpho-physiological and grain quality parameters. Significant variation was present among landraces for seedling stage and reproductive stage salinity tolerance. The nutrient composition analysis of grain revealed an increase in average grain protein and carbohydrate content under saline conditions. Evaluation of twenty-two SSR markers associated with the Saltol region validated RM140, RM1287 and RM562 as best markers to classify landraces for saline tolerance. Polymorphism Information Content and genetic diversity indices showed that the markers RM10748 and RM10864 were highly useful for distinguishing landraces. Further, to benefit the exploitation of heterosis, eleven maintainers were identified among tolerant landraces and these genotypes could be further developed into male sterile lines for production of salinity-tolerant rice hybrids. Comparison with ‘Pokkali’ for morpho-physiological traits along with molecular confirmation showed that the landraces ‘Doddabaikalu,’ Kalaadikonda,’ Gajagunda’ and ‘Anekombina batha’ were superior donors carrying genomic regions for salinity tolerance

Marker-assisted identification of novel genetic lines for salinity tolerance and their categorization for utilization in development of hybrid rice (Oryza sativa L.)

Identification of new sources of salinity-tolerant genotypes is prerequisite for rice breeding programs in different saline ecosystems. In the present experiment, we characterized 177 landraces from the Western Ghats of Karnataka under natural saline field conditions for two years using morpho-physiological and grain quality parameters. Significant variation was present among landraces for seedling stage and reproductive stage salinity tolerance. The nutrient composition analysis of grain revealed an increase in average grain protein and carbohydrate content under saline conditions. Evaluation of twenty-two SSR markers associated with the Saltol region validated RM140, RM1287 and RM562 as best markers to classify landraces for saline tolerance. Polymorphism Information Content and genetic diversity indices showed that the markers RM10748 and RM10864 were highly useful for distinguishing landraces. Further, to benefit the exploitation of heterosis, eleven maintainers were identified among tolerant landraces and these genotypes could be further developed into male sterile lines for production of salinity-tolerant rice hybrids. Comparison with ‘Pokkali’ for morpho-physiological traits along with molecular confirmation showed that the landraces ‘Doddabaikalu,’ Kalaadikonda,’ Gajagunda’ and ‘Anekombina batha’ were superior donors carrying genomic regions for salinity tolerance

Exploring the Multi-Seasonal Relationships between Yield Traits with Natural Screening of Rice Blast Disease Under Hot Spot Conditions

The experiment was conducted to study the comparative performance and blast disease screening&nbsp; 80 diverse rice cultivars including land races, obsolete varieties, modern cultivars and released varieties, local prevailing cultivars and advanced breeding/varietal lines as AICRIP testing trials for two successive seasons during Kharif-2021 and Kharif-2022 at AHRS Ponnampet, Karnataka- India, The results from ANOVA revealed that, MSS due to genotypes, were significant (p&lt;0.01 and p&lt;0.05) for all the yield traits studied. GYKH was varied from 270.65-6039.89, while 940.17-6039.88 with mean grain yield Kg/ha of 3596.01 and 3483.92 kg/ha during Kh-21 and Kh-22. High GCV and PCV with high heritability coupled with high GAM were observed for GYKH, while the remaining traits revealed low to medium GCV and PCV, heritability coupled with low to medium GAM. Correlation analysis revealed that significant and positive association was observed for PH, DFF, PL and GYKH. PCAs revealed that PC1, PC2 and PC3 showed 32.45%, 29.66% and 14.83% of contribution with 76.94% of total variation during Kharif-21 and 33.20%, 29.67% and 14.33% of contribution with 77.20% of variation for the studied traits during Kharif-22 respectively. Field screening of leaf and neck blast under natural hot spot area among 80 diverse genotypes resulted in identification of resistant sources as KPR-1, KPR-2, KHP-5, Mud-1014, IET-28515 and Kajajaya with promising yield performances

Analysis of Genetic Variability and Correlation in Rice (Oryza sativa L.) Recombinant Inbred Lines (F6) for Yield and Its Component Traits

grain yield and its component traits in 150 rice recombinant inbred lines, their parents and six checks at ICAR-IIRR, Hyderabad and AHRS, Kathalagere in wet 2022. The experiments were laid out in an augmented block design with five blocks. Phenotypic coefficients of variance were higher than genotypic coefficients of variance for all the traits across the locations. A joint consideration of high heritability in broad sense (h2) and genetic advance as per cent mean estimates were obtained for plant height, number of tillers, number of productive tillers, panicle length, number of grains per panicle, test weight, grain yield per plant suggesting that the traits were primarily under genetic control. Furthermore, high heritability (h2) and GAM recorded in these characters could be explained by additive gene action. However, high estimates (h2) combined with moderate GAM recorded for days to 50% flowering could be due to non-additive gene effect. Grain yield per plant recorded positive and significant correlation with the total number of grains per panicle (0.32***, 0.30***) and number of productive tillers per plant (0.21***, 0.26***) at both the locations. This result indicates that selection based on these two traits will be highly effective for yield improvement in rice

Patterns of Antiretroviral Therapy Use and Immunologic Profiles at Enrollment in the REPRIEVE Trial

BackgroundPatterns of antiretroviral therapy (ART) use and immunologic correlates vary globally, and contemporary trends are not well described.MethodsThe REPRIEVE trial (Randomized Trial to Prevent Vascular Events in HIV) enrolled persons with human immunodeficiency virus (HIV) who were aged 40-75 years, receiving ART, and had low-to-moderate cardiovascular disease risk. ART use was summarized within Global Burden of Disease (GBD) super-regions, with adjusted linear and logistic regression analyses examining associations with immune parameters and key demographics.ResultsA total of 7770 participants were enrolled, with a median age of 50 years (interquartile range, 45-55 years); 31% were female, 43% were black or African American, 15% were Asian, 56% had a body mass index &gt;25 (calculated as weight in kilograms divided by height in meters squared), and 49% were current or former smokers. The median CD4 T-cell count was 620/µL (interquartile range, 447-826/ µ L), and the median duration of prior ART use, 9.5 years (5.3-14.8) years. The most common ART regimens were nucleoside/nucleotide reverse-transcriptase inhibitor (NRTI) plus nonnucleoside reverse-transcriptase inhibitor (43%), NRTI plus integrase strand transfer inhibitor (25%), and NRTI plus protease inhibitor (19%). Entry ART varied by GBD region, with shifts during the trial enrollment period. In adjusted analyses, entry CD4 cell count and CD4/CD8 ratio were associated with GBD region, sex, entry regimen, duration of ART, and nadir CD4 cell count; CD4 and CD8 cell counts were also associated with body mass index and smoking status.ConclusionsThere were substantial variations in ART use by geographic region and over time, likely reflecting the local availability of specific medications, changes in treatment guidelines and provider/patient preferences. The analyses of CD4 cell counts and CD4/CD8 ratios may provide valuable insights regarding immune correlates and outcomes in people living with HIV.Clinical trials registrationNCT02344290