Download or read book Characterization of Sorghum Sorghum Bicolor l Moench Parental Lines and Prediction of Their Hybrid Performance Under Simulated Water and Population Density Stress written by Clement Kamau Karari and published by . This book was released on 2006 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Agronomic Genetic and Genomic Approaches for Predicting Heterosis in Sorghum Sorghum Bicolor L Moench written by Frank Maulana and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The approach used to identify inbred lines that can produce superior hybrids is costly and time-consuming. It requires creation of all possible crosses and evaluation of the crosses to estimate combining abilities for the desired traits. Predicting heterosis or hybrid performance in any way possible may help to reduce the number of crosses to be made and evaluated. In this study, four sets of experiments were conducted to determine whether heterosis can be predicted based on inbred line performance, genetic distance between parents and genomic prediction model. The first experiment was aimed at assessing the levels of genetic diversity, population structure and linkage disequilibrium (LD) in 279 public sorghum inbred lines, based on 66,265 SNPs generated using the genotyping-by-sequencing (GBS) platform. The inbred lines were developed at different times over the last two decades and harbor robust diversity in pedigree and agronomic characteristics. Some of the inbreds are resistant to Acetolactate synthase (ALS) and Acetyl co-enzyme-A carboxylase (ACC) inhibitor herbicides. The mean polymorphic information content (PIC) and gene diversity across the entire inbreds were 0.35 and 0.46, respectively with non-herbicide resistant inbreds harboring more diversity than the herbicide resistant ones. The population structure analysis clustered the inbred lines into three major subgroups according to pedigree and fertility-reaction with the maintainer lines (B-lines) distinctly forming a separate cluster. Analysis of molecular variance (AMOVA) revealed more variation within subgroups than among subgroups. Substantial linkage disequilibrium (LD) was detected between the markers in the population with marked variation between chromosomes. This information may facilitate the use of the inbreds in sorghum breeding programs and provide perspectives for optimizing marker density for gene mapping and marker-assisted breeding. The second experiment, based on 102 F1 hybrids developed by intercrossing closely and distantly related inbreds, was conducted to investigate the relationship of genetic distance between parents with hybrid vigor or heterosis. The F1 hybrids alongside their parents were evaluated at two environments in a randomized complete block design with three replications. The results show that correlations of genetic distance between parents with hybrid performance and heterosis were variable and dependent on the trait. Though most were statistically non-significant and not strong to be used as predictor for heterosis, the results tend to show that certain level of genetic distance between parents is needed to capture maximum heterosis and hybrid performance. The objective of the third research study was to determine whether traits measured on parents can be used to predict hybrid performance in sorghum and to assess the combining ability of selected inbreds. Forty-six parental inbred lines and 75 F1 hybrids generated from intercrossing the inbreds were evaluated in four environments in a randomized complete block design with three replications. The average performance of the parents (mid-parent) was significantly correlated with hybrid performance for thousand kernel weight, days to flowering and plant height. Significant general (GCA) and specific (SCA) combining abilities were observed for most traits, with highly significant GCA effects observed for most traits as compared to SCA indicating that additive genetic effects are more important in affecting the inheritance of the traits measured. Results show that studying parental inbred line performance could generate important information for predicting hybrid performance in sorghum. The fourth experiment was aimed at assessing the efficacy of genomic prediction of hybrid performance in sorghum. Genomic prediction was performed with five-fold cross-validation procedure on 204 F1 hybrids developed using 102 inbred lines. A total of 66,265 SNP markers generated using genotyping-by-sequencing were used in this study. Results showed that increasing training population size increased prediction accuracies for all traits with the effect being different for different traits. Also, considering additive effects alone versus additive and dominance effects in the model showed similar trend of prediction accuracy but the full model (considering both additive and dominance effects of the markers) provided better prediction at least for some of the traits. The results suggest that genomic prediction could become an effective tool for predicting the performance of untested sorghum hybrids thus adding efficiency to hybrid selection.
Download or read book Performance Stability Parameters Genetic Effects and Prediction of Performance in Single Three way and Double cross Hybrids of Sorghum Sorghum Bicolor L Moench written by George Anthony Ombakho and published by . This book was released on 1994 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Genetics of Yield Heterosis in Sorghum Sorghum Bicolor L Moench written by Jhansi Rani and published by LAP Lambert Academic Publishing. This book was released on 2014-01 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Post rainy sorghum is unique to India, which is mostly grown on residual soil moisture in southern states, subjected to various biotic and abiotic stresses. Keeping in view the low heterosis in post rainy hybrids compared to rainy season hybrids, the study was taken up with 41 genotypes to enumerate the approaches for enhancing the level of heterosis. There was a positive relationship between heterosis for grain yield and major yield components. Genetic diversity analysis showed importance of inter as well as intra group divergence in expression of heterosis. There was a general positive trend between hybrid yield and sca effect but at least one general combiner was involved in highest yielding crosses and there was positive relationship between heterosis and mean gca of parents. Major yield components were controlled by non additive gene effects hence it is proposed to breed parental lines with high gca effect with capability to produce high sca effect in hybrid combination to enhance the level of heterosis and productivity. The information in this book is useful for sorghum breeders and geneticists for formulating effective crop improvement programme.
Download or read book Gene Characterization and Marker Development in Sorghum Bicolor L Moench written by Sarah June Schloss and published by . This book was released on 2001 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of Caryopsis Development in Sorghum Bicolor L Moench written by Dan Herman Meckenstock and published by . This book was released on 1981 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physiological Characterization of Parents of Sorghum Mapping Populations Exposed to Water deficit Stress written by Regina Enninful and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Changing climate presents new challenges to agricultural production and global climate models project increased intensity and magnitude in water-deficit stress conditions in the future. This is especially challenging for the arid and semi-arid regions of the world, where sorghum forms an important component of the cropping system. The research objective was to characterize eleven genetically and geographically diverse sorghum Nested Association Mapping parental lines (Ajabsido, SC1103, SC265, P898012, SC35, Macia, SC283, SC1345, Segaolane, SC971 and RTx430 - the common parent) for shoot and root related physiological parameters during the vegetative and grain filling stages. Using a lysimeter based experiment in the greenhouse, water-deficit stress (55 % to 60 % field capacity) imposed for 15 days during the vegetative stage recorded significant variation between water-deficit stress and well-watered treatments for all physiological and agronomic traits regardless of the genotypic variance, except for rooting depth. The genotype by treatment interaction indicated stem height to be not only under genetic control but was subject to complex effects of the watering regimes. Transpiration efficiency and carbon isotope discrimination increased for water-deficit stressed plants. A significantly higher biomass partitioning to the roots was detected under water-deficit stress compared with the well-watered plants. In Ghana, another experiment focusing on the vegetative stage with two levels of water-deficit stress imposed on selected set of sorghum genotypes, recorded a greater decrease for shoot and root related traits under the more severe stress (50 % to 55 % FC; lasting for 21 days) than the moderate water-deficit condition (60 % to 65 % FC; lasting for 15 days). The mean cumulative water transpired (liters) during the 21 days period was 2.32 for the severe water-deficit stress, 6.88 for the moderate water-deficit stress, and 10.7 for the well-watered condition. In the grain filling experiments conducted in both the greenhouse and on the field, water-deficit stress induced variations in grain number and grain weight along different positions on the panicle among the tested genotypes. In this regard, differences in panicle positional grain number accounted for differences in panicle positional grain weight as the positional individual grain weight was not affected by the stress. Regardless of the watering treatments however, differences in grain numbers and grain weight among genotypes resulted from the diversity in panicle architecture other than grain filling dynamics. In both the greenhouse and field experiments, SC1103 did not record any significant difference between the watering treatment for all measured growth and yield traits. Spearman's rank correlations indicated the ability to select for water-deficit tolerance traits in the greenhouse that would partially represent rankings on the field. Generally, performance of genotypes such as SC35 portrayed a higher level of tolerance to water-deficit stress whereas other genotypes such as SC971 depicted significantly higher level of susceptibility. Findings from this research is helpful for providing pathways to map genomic regions responsible for increased resilience to water-deficit stress.
Download or read book Sorghum Molecular Breeding written by R. Madhusudhana and published by Springer. This book was released on 2015-08-20 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an up-to-date overview of international research work on sorghum. Its comprehensive coverage of our current understanding of transgenic development in sorghum and the strategies that are being applied in molecular breeding make this book unique. Important areas such as genetic diversity, QTL mapping, heterosis prediction, genomic and bioinformatics resources, post-genome sequencing developments, molecular markers development using bioinformatics tools, genetic transformation and transgenic research are also addressed. The availability of the genome sequence along with other recent developments in sequencing and genotyping technologies has resulted in considerable advances in the area of sorghum genomics. These in turn have led to the generation of a large number of DNA-based markers and resulted in the identification and fine mapping of QTL associated with grain yield, its component traits, biotic and abiotic stress tolerance as well as grain quality traits in sorghum. Though a large volume of information has accumulated over the years, especially following the sequencing of the sorghum genome, until now it was not available in a single reference resource. This book fills that gap by documenting advances in the genomics and transgenic research in sorghum and presenting critical reviews and future prospects. “Sorghum Molecular Breeding” is an essential guide for students, researchers and managers who are involved in the area of molecular breeding and transgenic research in sorghum and plant biologists in general.
Download or read book Evaluation of the Heterotic Potential of Sorghum Sorghum Bicolor L Moench Adapted to the Southern Africa Region written by Leo Thokoza Mpofu and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Sorghum [Sorghum bicolor (L.) Moench] production in Africa is widespread with low yields due to low inputs and the lack of sorghum hybrids. This situation has forced most of these farmers to grow maize hybrids since they are readily available in the seed market. Sorghum hybrids could be used if their potential was demonstrated. The objective of this study is to document the level of heterosis in Southern Africa sorghum germplasm. The performance of 52 F1 grain sorghum hybrids and their parental lines was evaluated in four environments. Measurements for grain yield, panicle exsertion, days to mid anthesis and plant height were analyzed to obtain estimates of high parent heterosis. High parent heterosis was observed to be 37.18% for yield, 82.77% for exsertion, 0.02% for days to mid anthesis and 23.7% for height. ICSR-939 and (87EON366*90EON328)-LD30 can be used as testers to develop more female lines for further hybrid seed production in breeding programs because they had the highest general combining ability. Protein content averaged 11.69%. ATx635 had significantly higher protein content than ATx631 (13.49% compared to 9.69%, respectively) and its hybrids had more protein than ATx631 hybrids (11.6% compared to 10.67% for ATx631). Mean heterosis for protein content was negative at -12.5%. This shows that hybrids had lower protein content than their parents since protein content is negatively correlated to grain yield ( -0.35**). Starch content averaged 72.13% and ATx631 hybrids had more starch than ATx635 hybrids (73.16 compared to 72.37% respectively). Two hybrids, ATx. 631/(87EON366*90EON328)-LD30 and ATx631/ ((TAM428*SV1)*CE151)-LD3 had the highest yields (5.04 t/ha and 4.93 t/ha, respectively). These hybrids also had small grains with good hardness and acceptable whiteness. They had good exsertion, flowered in good time and had acceptable plant heights. These two hybrids were compared to regional check varieties Macia and Tegemeo for all traits and they were either superior or within an acceptable range. These two hybrids are therefore recommended for release in the region. There is need therefore to start working on the various components of seed systems in the region so that seed of these two hybrids is made available to farmers who need the seed.
Download or read book Identification and Characterization of Sorghum Bicolor L Moench Lines with Resistance to Preharvest Grain Deterioration written by James Andrew Glueck and published by . This book was released on 1979 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Influence of Water Stress on the Performance of Sorghum Bicolor L Moench Cultivars written by Balaji Manmohan Nukal and published by . This book was released on 1989 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Tester Choice in Evaluating New Parental Lines in Grain Sorghum Sorghum Bicolor L Moench written by Chibwe Chungu and published by . This book was released on 1992 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Planting Geometry Hybrid Maturity and Population Density on Yield and Yield Components in Sorghum written by Kalaiyarasi Pidaran and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Prior studies indicate clumped planting can increase grain sorghum yield up to 45% under water deficit conditions by reducing tiller number, increasing radiation use efficiency, and preserving soil water for grain fill. The objective of this study was to evaluate effects of planting geometry on sorghum grain yield. The field study was conducted in seven environments with two sorghum hybrids, four populations, and two planting geometries. Crop responses included leaf area index, yield, and components of yield. Delayed planting decreased yield by 39%, and a later maturing hybrid increased yield, relative to an early hybrid, by 11% under water sufficiency. Clumped planting increased the fraction of fertile culms (culms which formed panicles) from 5-14%. It reduced the number of culms m−2 by 12% under water limiting conditions (at one of two locations) but increased culms m−2 16% under water sufficiency. Seeds per panicle and seed weight generally compensated for differences in panicles m−2, which were related to different planting population densities. Although agronomic characteristics of hybrids varying in maturity have been widely studied, little information exists concerning their physiological differences. Therefore, the objective of the greenhouse study was to determine if stomatal resistance, leaf temperature, and leaf chlorophyll content differed between two DeKalb grain sorghum [Sorghum bicolor (L.) Moench] hybrids. They were DKS 36-16 and DKS 44-20, of medium-early and medium maturity, respectively, when grown under field conditions in Kansas. Seeds were planted in a greenhouse. Stomatal resistance and leaf temperature were measured 55 days after planting with a Decagon Devices (Pullman, WA) diffusion porometer, and chlorophyll content was measured 119 days after planting with a Konica Minolta (Osaka, Japan) SPAD chlorophyll meter. The two hybrids did not differ in stomatal resistance, leaf temperature, chlorophyll content, height, and dry weight. Their difference in maturity was not evident under the greenhouse conditions. Future work needs to show if hybrids of different maturities vary in physiological characteristics.
Download or read book Evaluation of Selection Procedures in Multiple Environments to Identify Parent Lines for Grain Sorghum Hybrids Sorghum Bicolor L Moench written by Medson Chisi and published by . This book was released on 1993 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Influence of Different Population Densities on Yield and Some Agronomic and Morphological Characteristics of Three Grain Sorghum Hybrids written by Festo Samanya Owenya and published by . This book was released on 1977 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comprehensive Dissertation Index written by and published by . This book was released on 1973 with total page 1244 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparative Performance and Basis for Differences Among Sorghum Sorghum Bicolor L Moench Hybrids from Differenct Periods of Sorghum Improvement written by Yilma Kebede and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
