Genetic control of cone clusters and precocious flowering in Pinus sylvestris

1969 ◽  
Vol 47 (7) ◽  
pp. 1081-1084 ◽  
Author(s):  
A. H. Teich ◽  
M. J. Holst
Keyword(s):  
Genetic Variation ◽  
Pinus Sylvestris ◽  
Seed Yield ◽  
Normal Cone ◽  
Major Gene ◽  
Viable Seed ◽  
Breeding Programs ◽  
Genetic Studies ◽  
Precocious Flowering ◽  
The Cost

A Scots pine clone bearing cone clusters transmitted precocity to a portion of its progeny resulting from crosses to clones having normal cone distribution. Inheritance appeared to be governed by a single major gene whose expression was dominant or recessive depending upon which clone it was mated to. Differences of reciprocal crosses indicated maternal or cytoplasmic influence. This genetic variation in precocity can be used to reduce the generation interval, thereby facilitating genetic studies and breeding programs. Seed yield per pollination bag was several times greater for cone clusters than for normally distributed cones although viable seed per cone was 20% less. This can reduce the cost of producing hybrid seed if artificial pollination is required.

scholarly journals A New Breeding Strategy towards Introgression and Characterization of Stay-Green QTL for Drought Tolerance in Sorghum

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 598
Author(s):  
Nasrein Mohamed Kamal ◽  
Yasir Serag Alnor Gorafi ◽  
Hanan Abdeltwab ◽  
Ishtiag Abdalla ◽  
Hisashi Tsujimoto ◽  
...  
Keyword(s):  
Phenotypic Expression ◽  
Phenotypic Selection ◽  
Breeding Strategy ◽  
Stay Green ◽  
Breeding Programs ◽  
The Public ◽  
Drought Tolerant ◽  
Selection Step ◽  
The Cost

Several marker-assisted selection (MAS) or backcrossing (MAB) approaches exist for polygenic trait improvement. However, the implementation of MAB remains a challenge in many breeding programs, especially in the public sector. In MAB introgression programs, which usually do not include phenotypic selection, undesired donor traits may unexpectedly turn up regardless of how expensive and theoretically powerful a backcross scheme may be. Therefore, combining genotyping and phenotyping during selection will improve understanding of QTL interactions with the environment, especially for minor alleles that maximize the phenotypic expression of the traits. Here, we describe the introgression of stay-green QTL (Stg1–Stg4) from B35 into two sorghum backgrounds through an MAB that combines genotypic and phenotypic (C-MAB) selection during early backcross cycles. The background selection step is excluded. Since it is necessary to decrease further the cost associated with molecular marker assays, the costs of C-MAB were estimated. Lines with stay-green trait and good performance were identified at an early backcross generation, backcross two (BC2). Developed BC2F4 lines were evaluated under irrigated and drought as well as three rainfed environments varied in drought timing and severity. Under drought conditions, the mean grain yield of the most C-MAB-introgression lines was consistently higher than that of the recurrent parents. This study is one of the real applications of the successful use of C-MAB for the development of drought-tolerant sorghum lines for drought-prone areas.

INHERITANCE OF RESISTANCE TO NET BLOTCH IN BARLEY. I. FACTORS AFFECTING THE PENETRANCE AND EXPRESSIVITY OF GENE(S) CONDITIONING HOST RESISTANCE

1969 ◽  
Vol 11 (3) ◽  
pp. 587-591 ◽  
Author(s):  
T. N. Khan
Keyword(s):  
Environmental Conditions ◽  
Net Blotch ◽  
Host Reaction ◽  
Susceptible Parent ◽  
Breeding Programs ◽  
Genetic Studies ◽  
Factors Affecting ◽  
Drechslera Teres ◽  
Resistant Varieties ◽  
High Level

Variability in the host-reaction of barley to infection by Drechslera teres was examined in the parents and progeny of selected crosses under different environmental conditions of testing.The Ethiopian variety C.I. 5791 exhibits a consistently high level of resistance under a range of environmental conditions, which is in contrast to the Manchurian variety C.I. 2330. The sensitivity of the genes for resistance possessed by these varieties to environmental modifications is considered to depend upon their respective genetic backgrounds. Furthermore, variability of host reaction in the progeny of these resistant varieties was shown to be influenced by the genetic background of the susceptible parent used.The implications of these findings in the conduct and interpretation of genetic studies and in backcross breeding programs is discussed.

scholarly journals Focused Strategies for Defining the Genetic Architecture of Congenital Heart Defects

Genes ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 827
Author(s):  
Lisa J. Martin ◽  
D Woodrow Benson
Keyword(s):  
Genetic Variation ◽  
Congenital Heart Defects ◽  
Heart Development ◽  
Genetic Architecture ◽  
Congenital Heart ◽  
Rare Variants ◽  
Heart Defects ◽  
Genetic Origin ◽  
Genetic Studies ◽  
The Ideal

Congenital heart defects (CHD) are malformations present at birth that occur during heart development. Increasing evidence supports a genetic origin of CHD, but in the process important challenges have been identified. This review begins with information about CHD and the importance of detailed phenotyping of study subjects. To facilitate appropriate genetic study design, we review DNA structure, genetic variation in the human genome and tools to identify the genetic variation of interest. Analytic approaches powered for both common and rare variants are assessed. While the ideal outcome of genetic studies is to identify variants that have a causal role, a more realistic goal for genetic analytics is to identify variants in specific genes that influence the occurrence of a phenotype and which provide keys to open biologic doors that inform how the genetic variants modulate heart development. It has never been truer that good genetic studies start with good planning. Continued progress in unraveling the genetic underpinnings of CHD will require multidisciplinary collaboration between geneticists, quantitative scientists, clinicians, and developmental biologists.

scholarly journals Genetic variation for seed yield components of Westerwold ryegrass (Lolium multiflorum var. westerwoldicum).

1989 ◽  
Vol 37 (2) ◽  
pp. 119-127 ◽  
Author(s):  
A. Elgersma ◽  
A.P.M. Den Nijs ◽  
F.A. Van Eeuwijk
Keyword(s):  
Genetic Variation ◽  
Seed Yield ◽  
Yield Components ◽  
Lolium Multiflorum ◽  
Genotypic Variation ◽  
Yield Component ◽  
Path Analyses ◽  
Seed Yield Components ◽  
High Heritability ◽  
1000 Grain Weight

Genetic variation for seed yield components was studied in 4 diploid varieties of Westerwold ryegrass, and 19 genotypes from each variety were grown in the field in 2 clonal replicate rows (minirows). The number of inflorescences/minirow, the numbers of spikelets/inflorescence and florets and seeds/spikelet, 1000-grain weight and seed yield/minirow were determined. Floret site utilization (FSU) was calculated as (seeds/floret) x 100%. Genotypic variation and heritabilities were calculated. Correlation studies and path analyses were carried out in each variety separately. Among varieties, no significant differences occurred for seed yield. However, within varieties large genetic variation was present for both seed yield and yield components. Path analyses revealed that relationships between seed yield components differed to a great extent among varieties. FSU was the major yield component in 3 varieties, but in one variety inflorescence number was the most important yield component. There was ample scope for genetic improvement of seed yield. FSU had a very high heritability and was not correlated with any of the other seed yield components. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Effects of Mutagens on Morphological traits of Psoralea corylifolia-A Medicinally Important Plant

2020 ◽  
Vol 26 (2) ◽  
Author(s):  
Ajey Karan Chaudhari ◽  
Anand Prakash Singh ◽  
B R Chaudhary
Keyword(s):  
Plant Height ◽  
Seed Yield ◽  
Morphological Traits ◽  
Mutation Breeding ◽  
Yield Potential ◽  
Mutagenic Potential ◽  
Breeding Programs ◽  
Methane Sulphonate ◽  
Flowering Initiation ◽  
Yield Quality

Mutation breeding like in other plants can significantly strengthen medicinal plants breeding programs and help to produce novel varieties with higher yield potential and improved yield quality. The dry and healthy seeds of P. corylifolia IC 111228 were subjected to mutagenic treatments namely ethyl methane sulphonate (EMS) and sodium azide (SA). The treatment concentrations 15mM, 30mM, 45mM and 60mM of EMS and 1mM, 2mM, 3mM and 4mM of SA were chosen to evaluate the mutagenic potential in either case. The morphological traits were evaluated in M1 generation viz. plant height, days to flowering initiation, seed yield/plant and 100-seed weight. In EMS treatment 15 mM increased the plant height and seed yield, while in SA treatment 4 mM increased the seed yield/plant and 100-seed yield.

scholarly journals Genetic studies revealed differences between European and North American populations of Calypogeia azurea

2016 ◽  
Vol 42 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Katarzyna Buczkowska ◽  
Alina Bączkiewicz ◽  
Patrycja Gonera
Keyword(s):  
Genetic Variation ◽  
North America ◽  
Genetic Distance ◽  
Gene Diversity ◽  
Oil Bodies ◽  
Genetic Studies ◽  
Isozyme Loci ◽  
The Mean ◽  
Different Parts ◽  
Nei's Genetic Distance

Abstract Calypogeia azurea, a widespread, subboreal-montane liverwort species, is one of a few representatives of the Calypogeia genus that are characterized by the occurrence of blue oil bodies. The aim of the study was to investigate the genetic variation and population structure of C. azurea originating from different parts of its distribution range (Europe and North America). Plants of C. azurea were compared with C. peruviana, another Calypogeia species with blue oil bodies. In general, 339 gametophytes from 15 populations of C. azurea were examined. Total gene diversity (HT) estimated on the basis of nine isozyme loci of C. azurea at the species level was 0.201. The mean Nei’s genetic distance between European populations was equal to 0.083, whereas the mean genetic distance between populations originating from Europe and North America was 0.413. The analysis of molecular variance (AMOVA) showed that 69% of C. azurea genetic variation was distributed among regions (Europe and North America), 15% - among populations within regions, and 16% - within populations. Our study revealed that C. azurea showed genetic diversity within its geographic distribution. All examined samples classified as C. azurea differed in respect of isozyme patterns from C. peruviana.

scholarly journals Genetic variation in arthropod vectors of disease-causing organisms: obstacles and opportunities.

1996 ◽  
Vol 9 (3) ◽  
pp. 301-320 ◽  
Author(s):  
R H Gooding
Keyword(s):  
Genetic Variation ◽  
Temporal Variation ◽  
Biochemical Genetics ◽  
Genetic Structuring ◽  
Genetic Studies ◽  
Arthropod Vectors ◽  
Biochemical Genetic ◽  
Genetic Techniques

An overview of the genetic variation in arthropods that transmit pathogens to vertebrates is presented, emphasizing the genetics of vector-pathogen relationships and the biochemical genetics of vectors. Vector-pathogen interactions are reviewed briefly as a prelude to a discussion of the genetics of susceptibility and refractoriness in vectors. Susceptibility to pathogens is controlled by maternally inherited factors, sex-linked dominant alleles, and dominant and recessive autosomal genes. There is widespread interpopulation (including intercolony) and temporal variation in susceptibility to pathogens. The amount of biochemical genetic variation in vectors is similar to that found in other invertebrates. However, the amount varies widely among species, among populations within species, and temporally within populations. Biochemical genetic studies show that there is considerable genetic structuring of many vectors at the local, regional, and global levels. It is argued that genetic variation in vectors is critical in understanding vector-pathogen interactions and that genetic variation in vectors creates both obstacles to and opportunities for application of genetic techniques to the control of vectors.

scholarly journals Use of Targeted Amplicon Sequencing in Peanut to Generate Allele Information on Allotetraploid Sub-Genomes

Genes ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1220
Author(s):  
Roshan Kulkarni ◽  
Ratan Chopra ◽  
Jennifer Chagoya ◽  
Charles E. Simpson ◽  
Michael R. Baring ◽  
...  
Keyword(s):  
Cost Effective ◽  
Amplicon Sequencing ◽  
Routine Practice ◽  
Specific Information ◽  
Illumina Hiseq ◽  
Breeding Programs ◽  
Polymorphic Snps ◽  
Cost Effective Approach ◽  
A Genome ◽  
The Cost

The use of molecular markers in plant breeding has become a routine practice, but the cost per accession can be a hindrance to the routine use of Quantitative Trait Loci (QTL) identification in breeding programs. In this study, we demonstrate the use of targeted re-sequencing as a proof of concept of a cost-effective approach to retrieve highly informative allele information, as well as develop a bioinformatics strategy to capture the genome-specific information of a polyploid species. SNPs were identified from alignment of raw transcriptome reads (2 × 50 bp) to a synthetic tetraploid genome using BWA followed by a GATK pipeline. Regions containing high polymorphic SNPs in both A genome and B genomes were selected as targets for the resequencing study. Targets were amplified using multiplex PCR followed by sequencing on an Illumina HiSeq. Eighty-one percent of the SNP calls in diploids and 68% of the SNP calls in tetraploids were confirmed. These results were also confirmed by KASP validation. Based on this study, we find that targeted resequencing technologies have potential for obtaining maximum allele information in allopolyploids at reduced cost.

Sign in / Sign up

Export Citation Format

Share Document