Maize evolution
•
4 likes•1,071 views
- The earliest remains of maize were found in Mexico around 6250 years ago. - There have been three main hypotheses for the origin of maize: that it originated from a combination of species (Tripartite), from a wild grass called teosinte, or from recombination between teosinte and another wild grass (Tripsacum). - Current evidence strongly supports that maize was domesticated from a wild grass called teosinte in Mexico through selection of mutations that improved traits like ear development and plant architecture over several thousand years starting around 12,000 years ago.
Report
Share
Report
Share
Recommended
Presentation on Evolution of Wheat
Bread wheat is an allohexaploid species that evolved through two hybridization events followed by chromosome doubling. The first event involved hybridization of Triticum urartu and Triticum speltoides, producing a tetraploid species. The second event involved hybridization of the tetraploid with Triticum tauschii, producing hexaploid wheat with three complete genome sets. Most evidence now suggests the tetraploid intermediate was produced from hybridization of Triticum urartu and Aegilops speltoides, not Triticum speltoides as previously thought. Hexaploid wheat then evolved on farmers' fields through hybridization of the tetraploid or domesticated em
History of plant breeding(Pre and post mendelian era)
This document provides an overview of the history of plant breeding from pre-Mendelian to modern eras, objectives of plant breeding, and characteristics improved through breeding. It discusses early developments before 1900 including Linnaeus' binomial nomenclature system. The Mendelian era from 1900-1920 saw the rediscovery of Mendel's work. Post-Mendelian developments from 1921-1950 included Wright's mating systems and the concept of heterosis. Modern breeding from 1950 onward utilized techniques like wide hybridization and mutation breeding. Objectives include increased yield, quality, biotic/abiotic stress resistance, and earliness. Traits improved include these objectives in crops like wheat, rice, cotton, and more.
Marker assisted selection
Marker-assisted selection (MAS) is a plant breeding method that uses DNA markers to select for desirable traits. It allows breeders to select plants earlier in development compared to phenotypic selection. MAS has advantages like being unaffected by environment and ability to select for recessive traits, but may be more expensive initially than conventional methods. Careful analysis of costs and benefits is needed to determine if MAS is advantageous for a particular program over traditional breeding. MAS requires tightly linked markers, knowledge of marker-trait associations, and data management to be effective. A variety of MAS approaches exist like backcrossing, pyramiding, and combined MAS and phenotypic selection.
Evolution and cytogenetics of maize
- Maize originated in Mexico around 12,000-6,000 years ago from a wild grass called teosinte. Over generations of cultivation and selection by humans, teosinte evolved into modern maize through the accumulation of mutations.
- Three main hypotheses for the origin of maize include: the tripartite hypothesis involving teosinte and the grass Tripsacum; the teosinte hypothesis of maize evolving directly from teosinte; and the recombination hypothesis involving ancient hybridization between teosinte and Tripsacum.
- Cytogenetic and molecular evidence supports the teosinte hypothesis, showing that teosinte has the same chromosome number as maize and similar isozyme
Cytogenetic techniques for gene location and transfer
This document discusses various cytogenetic techniques for gene location and transfer. It describes techniques for locating genes such as using structural and numerical chromosomal aberrations, chromosome banding, and in situ hybridization. Structural aberrations discussed include deficiencies, inversions, and translocations. Numerical aberrations discussed include aneuploids like trisomics, monosomics, and nullisomics. The document also describes techniques for transferring genes between species such as transferring whole genomes, whole chromosomes, chromosome arms, and through various types of interchanges. Specific examples of using these techniques in plants are provided.
Reverse Breeding
Reverse breeding is a novel plant breeding technique that allows the development of parental lines directly from any superior heterozygous plant. It involves suppressing meiotic recombination to produce gametes with whole parental chromosome sets, followed by doubling of haploids to generate parental lines. Two case studies demonstrate using RNAi to silence meiotic genes in Arabidopsis thaliana, producing parental lines that reconstitute the original hybrid when crossed. A second technique, marker-assisted reverse breeding, uses high-density SNP genotyping instead of gene silencing to select maize lines similar to original parents within one year. Reverse breeding techniques accelerate breeding and facilitate hybrid improvement without prior knowledge of parental lines.
Definitions, variety production release and notification in india and pakist
1. The document discusses concepts related to variety release and seed production systems in India and other countries like Pakistan. It defines key terms and describes procedures for variety testing, release, and notification.
2. Variety testing in India involves evaluation through station trials, multilocation trials, national trials, and on-farm trials over several years before potential release. Superior varieties identified through this process may be recommended for release.
3. Release and notification involves recommendation by variety release committees at the state and national level, followed by an official notification from the Government of India allowing commercial seed production.
Mating designs..
It comprises on mating designs used in plant breeding programs. 6 basic mating designs are briefly explained in it with their requirements as well limiting factors...
Recommended
Presentation on Evolution of Wheat
Bread wheat is an allohexaploid species that evolved through two hybridization events followed by chromosome doubling. The first event involved hybridization of Triticum urartu and Triticum speltoides, producing a tetraploid species. The second event involved hybridization of the tetraploid with Triticum tauschii, producing hexaploid wheat with three complete genome sets. Most evidence now suggests the tetraploid intermediate was produced from hybridization of Triticum urartu and Aegilops speltoides, not Triticum speltoides as previously thought. Hexaploid wheat then evolved on farmers' fields through hybridization of the tetraploid or domesticated em
History of plant breeding(Pre and post mendelian era)
This document provides an overview of the history of plant breeding from pre-Mendelian to modern eras, objectives of plant breeding, and characteristics improved through breeding. It discusses early developments before 1900 including Linnaeus' binomial nomenclature system. The Mendelian era from 1900-1920 saw the rediscovery of Mendel's work. Post-Mendelian developments from 1921-1950 included Wright's mating systems and the concept of heterosis. Modern breeding from 1950 onward utilized techniques like wide hybridization and mutation breeding. Objectives include increased yield, quality, biotic/abiotic stress resistance, and earliness. Traits improved include these objectives in crops like wheat, rice, cotton, and more.
Marker assisted selection
Marker-assisted selection (MAS) is a plant breeding method that uses DNA markers to select for desirable traits. It allows breeders to select plants earlier in development compared to phenotypic selection. MAS has advantages like being unaffected by environment and ability to select for recessive traits, but may be more expensive initially than conventional methods. Careful analysis of costs and benefits is needed to determine if MAS is advantageous for a particular program over traditional breeding. MAS requires tightly linked markers, knowledge of marker-trait associations, and data management to be effective. A variety of MAS approaches exist like backcrossing, pyramiding, and combined MAS and phenotypic selection.
Evolution and cytogenetics of maize
- Maize originated in Mexico around 12,000-6,000 years ago from a wild grass called teosinte. Over generations of cultivation and selection by humans, teosinte evolved into modern maize through the accumulation of mutations.
- Three main hypotheses for the origin of maize include: the tripartite hypothesis involving teosinte and the grass Tripsacum; the teosinte hypothesis of maize evolving directly from teosinte; and the recombination hypothesis involving ancient hybridization between teosinte and Tripsacum.
- Cytogenetic and molecular evidence supports the teosinte hypothesis, showing that teosinte has the same chromosome number as maize and similar isozyme
Cytogenetic techniques for gene location and transfer
This document discusses various cytogenetic techniques for gene location and transfer. It describes techniques for locating genes such as using structural and numerical chromosomal aberrations, chromosome banding, and in situ hybridization. Structural aberrations discussed include deficiencies, inversions, and translocations. Numerical aberrations discussed include aneuploids like trisomics, monosomics, and nullisomics. The document also describes techniques for transferring genes between species such as transferring whole genomes, whole chromosomes, chromosome arms, and through various types of interchanges. Specific examples of using these techniques in plants are provided.
Reverse Breeding
Reverse breeding is a novel plant breeding technique that allows the development of parental lines directly from any superior heterozygous plant. It involves suppressing meiotic recombination to produce gametes with whole parental chromosome sets, followed by doubling of haploids to generate parental lines. Two case studies demonstrate using RNAi to silence meiotic genes in Arabidopsis thaliana, producing parental lines that reconstitute the original hybrid when crossed. A second technique, marker-assisted reverse breeding, uses high-density SNP genotyping instead of gene silencing to select maize lines similar to original parents within one year. Reverse breeding techniques accelerate breeding and facilitate hybrid improvement without prior knowledge of parental lines.
Definitions, variety production release and notification in india and pakist
1. The document discusses concepts related to variety release and seed production systems in India and other countries like Pakistan. It defines key terms and describes procedures for variety testing, release, and notification.
2. Variety testing in India involves evaluation through station trials, multilocation trials, national trials, and on-farm trials over several years before potential release. Superior varieties identified through this process may be recommended for release.
3. Release and notification involves recommendation by variety release committees at the state and national level, followed by an official notification from the Government of India allowing commercial seed production.
Mating designs..
It comprises on mating designs used in plant breeding programs. 6 basic mating designs are briefly explained in it with their requirements as well limiting factors...
Genetical and physiological basis of heterosis and inbreeding
This document discusses the genetic and physiological basis of heterosis and inbreeding depression. It defines heterosis as the superiority of F1 hybrids over their parents in traits like yield, vigor and adaptation. The document discusses two main theories for the genetic basis of heterosis - the dominance hypothesis, which states that heterosis is due to the masking of deleterious recessive alleles by dominant alleles, and the overdominance hypothesis, where the heterozygote is superior to either homozygote. Physiologically, heterosis is manifested through increased embryo weight, higher early seedling growth rates, and greater nutrient absorption in hybrids. Inbreeding depression is the opposite of heterosis and results from mating closely related individuals and the
MARKER ASSISTED SELECTION
MARKER ASSISTED SELECTION
Main features of marker aided selection
PROCEDURE FOR MAS
Marker assisted backcrossing (MABC)
Biometrical Techniques in Plant Breeding
Power Point is deals with the different aspects of Quantitative genetics in plant breeding it converse Basic Principles of Biometrical Genetics, estimation of Variability, Correlation, Principal Component Analysis, Path analysis, Different Matting design and Stability so on
LINE X TESTER ANALYSIS
This topic covers the important aspect of Quantitative Genetics. Anyone pursuing masters in Genetics and plant breeding can use this topic.
production of double haploid plants
The document discusses the production of double haploid plants through anther and pollen culture techniques. It provides background on the history of double haploid development, the importance of double haploids in plant breeding, and methods used to induce haploids including anther culture, pollen culture, ovary slice culture, and ovule culture. Key factors influencing anther culture success are also reviewed, such as genotype, culture medium, microspore stage, temperature, and donor plant physiology. Advantages and disadvantages of generating double haploid lines are presented.
Mapping population ppt
This document discusses different types of mapping populations used in genetic mapping. It describes F2, backcross, double haploid, recombinant inbred line, and near isogenic line populations. For each type, it provides details on how they are developed and their advantages and disadvantages. It also discusses how marker segregation ratios differ depending on the population type and marker dominance. The document recommends using short-term mapping populations initially for preliminary mapping but developing long-term populations like recombinant inbred lines for global mapping projects.
Molecular Breeding in Plants is an introduction to the fundamental techniques...
Molecular Breeding in Plants is an introduction to the fundamental techniques...UNIVERSITI MALAYSIA SABAH
The document discusses molecular genetics and breeding in plants. It begins by introducing Arabidopsis thaliana as a model plant and describes its small genome size, which was advantageous for early genome sequencing efforts. It notes that the A. thaliana genome contains 5 chromosomes totaling 115 Mbp and encodes 25,498 genes. The document then discusses various aspects of the A. thaliana genome structure, organization, and chromosomes. It also briefly describes the chloroplast and mitochondrial DNA structures. The remainder of the document focuses on introducing concepts in plant genetics and molecular breeding techniques.Genetic diversity analysis
The presentation was done as part of the course STAT 504 titled Quantitative Genetics in Second Semester of MSc. Agricultural Statistics at Agricultural College, Bapatla under ANGRAU, Andhra Pradesh
Gene pyramiding
Gene pyramiding or stacking can be defined as a process of combining two or more genes from multiple parents to develop elite lines and varieties.
Presentation on Alien Addition Line
Wide hybridization is a technique used to transfer agriculturally important traits from alien species to cultivated plants. It allows for greater genetic variability but can be hampered by issues like poor crossability and hybrid sterility. These barriers have been overcome through techniques like the use of growth hormones, improved culture conditions, chromosome doubling, and bridge crosses. Alien addition lines carry one chromosome pair from another species in addition to the parent species' normal chromosomes. They allow for the transfer of traits like disease resistance while limiting the introduction of undesirable genes. Alien addition lines have been developed in several important crop species like wheat and tobacco.
Balanced tertiary trismoics - Hybrid seed production
The term balanced tertiary trisomic has three words of which (1) “trisomic” indicates the presence of extra chromosome, (2) “tertiary” indicates that the extra chromosome is a trans-located chromosome, and (3) “balanced” refers to the breeding behaviour of the trisomic.
Ramage defined the BTT as a tertiary trisomic constructed in such a way that the dominant allele of a marker gene, closely linked with the translocation breakpoint of the extra chromosome is carried on the extra chromosome, and the recessive allele is carried on the two normal chromosomes that constitute the diploid complement. The dominant marker gene may be located on the centromere segment or the trans-located segment of the extra chromosome.
Intoduction to plant breeding
This document provides information about a plant breeding course including its objectives. It begins with details about the course such as its name, credit hours, and presenter. It then discusses definitions of plant breeding and the objectives of plant breeding which include higher yields, improved quality, disease and insect resistance, and changes in maturity duration among other traits. The document lists 12 main objectives of plant breeding and provides examples for each one. It concludes with information about international agricultural research centers.
Molecular plant breeding some basic information
I would like to share this presentation file.
Some basics information regarding to molecular plant breeding, hope this help the beginner who start working in this field.
Thanks for many original source of information (mainly from slideshare.net, IRRI, CIMMYT and any paper received from professor and some over the internet)
Cotton evolution at a glance
Cotton, ‘King of fibre’ is the premier cash crop in India
It is cultivated in tropical and subtropical regions of more than 80 countries of the world.
Cotton belongs to family Malvaceae and genus Gossypium
India is the pioneer country for the cultivation of cotton hybrids on commercial scale. After releasing of Hy.4 developed by Dr.C.T.Patel from 1971 from Main Cotton Research Station, Surat.
Cotton is providing livelihood directly and indirectly to over 60 million people and accounting for about 16 per cent of India’s export earnings.
Play a vital role in agriculture, industry, social and monetary affairs of country’s economy. .
More than 150 cotton hybrids have been released by various State Agricultural Universities and private seed companies.
Distant hybridization
Distant hybridization involves crossing individuals from different plant species or genera. It has been used to transfer desirable traits like disease resistance between crops. Some key challenges include hybrid sterility and incompatible crosses due to genetic differences between parental species. Techniques like embryo rescue and colchicine treatment have helped produce new crops through wide crosses, such as Nerica rice and triticale wheat-rye hybrids. Distant hybridization remains limited by barriers like hybrid breakdown but has achieved successes in improving crop varieties.
19. inbred lines development
1. Inbred lines are developed through repeated self-pollination or inbreeding of plants over multiple generations to produce genotypes that are homozygous and genetically uniform.
2. The pedigree method is most commonly used to develop maize inbred lines, involving self-pollination over 6-7 generations with selection of desirable plants each generation.
3. Doubled haploid lines can also be used, in which haploid cells are induced and then chromosome doubled to instantly produce completely homozygous lines.
Nature and components of variability
Types and components of variation, phenotypic, genotypic and environmental variation, additive , dominance and epistatic variance
Biparental mating design
Best of presentation prepared for better understanding of biparental mating design under the guidance of Dr. S.K. Singh.
Concept of combining ability
IN detailed explanation about combining ability, SCA, GCA, formulas to derive GCA and SCA, significance, examples to explain, case studies.
Apomixis
A game changer in plant breeding
,powerful breeding tool ,genetics ,asexual reproduction ,apomixis technology ,food ,agriculture research ,agriculture ,apomixis
Maize origin.pptx
This document discusses the genetics and evolution of maize. It presents several hypotheses for the origin of maize, including the tripartite hypothesis involving Tripsacum, the catastrophic sexual transmutation theory, and the teosinte hypothesis. The document argues that most geneticists now accept that maize was domesticated from a wild grass called teosinte (Zea mays ssp. parviglumis) based on evidence from chromosome studies, isoenzyme analysis, and the ability to produce fertile hybrids between maize and teosinte.
Evolutionary significance of tb1 locus in Maize
The document discusses the evolution and domestication of maize from its wild ancestor, teosinte. It describes three hypotheses for the origin of maize and provides evidence that teosinte is the wild progenitor. Maize was domesticated in Mexico from a form of teosinte called Balsas teosinte. Key differences between maize and teosinte involved increased apical dominance and changes to inflorescence in maize. The tb1 gene was identified as playing a major role in these differences, with the maize version expressed at higher levels and regulating branching. Studies showed selection led to overexpression of tb1 during domestication, transforming teosinte architecture into the maize plant of today.
More Related Content
What's hot
Genetical and physiological basis of heterosis and inbreeding
This document discusses the genetic and physiological basis of heterosis and inbreeding depression. It defines heterosis as the superiority of F1 hybrids over their parents in traits like yield, vigor and adaptation. The document discusses two main theories for the genetic basis of heterosis - the dominance hypothesis, which states that heterosis is due to the masking of deleterious recessive alleles by dominant alleles, and the overdominance hypothesis, where the heterozygote is superior to either homozygote. Physiologically, heterosis is manifested through increased embryo weight, higher early seedling growth rates, and greater nutrient absorption in hybrids. Inbreeding depression is the opposite of heterosis and results from mating closely related individuals and the
MARKER ASSISTED SELECTION
MARKER ASSISTED SELECTION
Main features of marker aided selection
PROCEDURE FOR MAS
Marker assisted backcrossing (MABC)
Biometrical Techniques in Plant Breeding
Power Point is deals with the different aspects of Quantitative genetics in plant breeding it converse Basic Principles of Biometrical Genetics, estimation of Variability, Correlation, Principal Component Analysis, Path analysis, Different Matting design and Stability so on
LINE X TESTER ANALYSIS
This topic covers the important aspect of Quantitative Genetics. Anyone pursuing masters in Genetics and plant breeding can use this topic.
production of double haploid plants
The document discusses the production of double haploid plants through anther and pollen culture techniques. It provides background on the history of double haploid development, the importance of double haploids in plant breeding, and methods used to induce haploids including anther culture, pollen culture, ovary slice culture, and ovule culture. Key factors influencing anther culture success are also reviewed, such as genotype, culture medium, microspore stage, temperature, and donor plant physiology. Advantages and disadvantages of generating double haploid lines are presented.
Mapping population ppt
This document discusses different types of mapping populations used in genetic mapping. It describes F2, backcross, double haploid, recombinant inbred line, and near isogenic line populations. For each type, it provides details on how they are developed and their advantages and disadvantages. It also discusses how marker segregation ratios differ depending on the population type and marker dominance. The document recommends using short-term mapping populations initially for preliminary mapping but developing long-term populations like recombinant inbred lines for global mapping projects.
Molecular Breeding in Plants is an introduction to the fundamental techniques...
Molecular Breeding in Plants is an introduction to the fundamental techniques...UNIVERSITI MALAYSIA SABAH
The document discusses molecular genetics and breeding in plants. It begins by introducing Arabidopsis thaliana as a model plant and describes its small genome size, which was advantageous for early genome sequencing efforts. It notes that the A. thaliana genome contains 5 chromosomes totaling 115 Mbp and encodes 25,498 genes. The document then discusses various aspects of the A. thaliana genome structure, organization, and chromosomes. It also briefly describes the chloroplast and mitochondrial DNA structures. The remainder of the document focuses on introducing concepts in plant genetics and molecular breeding techniques.Genetic diversity analysis
The presentation was done as part of the course STAT 504 titled Quantitative Genetics in Second Semester of MSc. Agricultural Statistics at Agricultural College, Bapatla under ANGRAU, Andhra Pradesh
Gene pyramiding
Gene pyramiding or stacking can be defined as a process of combining two or more genes from multiple parents to develop elite lines and varieties.
Presentation on Alien Addition Line
Wide hybridization is a technique used to transfer agriculturally important traits from alien species to cultivated plants. It allows for greater genetic variability but can be hampered by issues like poor crossability and hybrid sterility. These barriers have been overcome through techniques like the use of growth hormones, improved culture conditions, chromosome doubling, and bridge crosses. Alien addition lines carry one chromosome pair from another species in addition to the parent species' normal chromosomes. They allow for the transfer of traits like disease resistance while limiting the introduction of undesirable genes. Alien addition lines have been developed in several important crop species like wheat and tobacco.
Balanced tertiary trismoics - Hybrid seed production
The term balanced tertiary trisomic has three words of which (1) “trisomic” indicates the presence of extra chromosome, (2) “tertiary” indicates that the extra chromosome is a trans-located chromosome, and (3) “balanced” refers to the breeding behaviour of the trisomic.
Ramage defined the BTT as a tertiary trisomic constructed in such a way that the dominant allele of a marker gene, closely linked with the translocation breakpoint of the extra chromosome is carried on the extra chromosome, and the recessive allele is carried on the two normal chromosomes that constitute the diploid complement. The dominant marker gene may be located on the centromere segment or the trans-located segment of the extra chromosome.
Intoduction to plant breeding
This document provides information about a plant breeding course including its objectives. It begins with details about the course such as its name, credit hours, and presenter. It then discusses definitions of plant breeding and the objectives of plant breeding which include higher yields, improved quality, disease and insect resistance, and changes in maturity duration among other traits. The document lists 12 main objectives of plant breeding and provides examples for each one. It concludes with information about international agricultural research centers.
Molecular plant breeding some basic information
I would like to share this presentation file.
Some basics information regarding to molecular plant breeding, hope this help the beginner who start working in this field.
Thanks for many original source of information (mainly from slideshare.net, IRRI, CIMMYT and any paper received from professor and some over the internet)
Cotton evolution at a glance
Cotton, ‘King of fibre’ is the premier cash crop in India
It is cultivated in tropical and subtropical regions of more than 80 countries of the world.
Cotton belongs to family Malvaceae and genus Gossypium
India is the pioneer country for the cultivation of cotton hybrids on commercial scale. After releasing of Hy.4 developed by Dr.C.T.Patel from 1971 from Main Cotton Research Station, Surat.
Cotton is providing livelihood directly and indirectly to over 60 million people and accounting for about 16 per cent of India’s export earnings.
Play a vital role in agriculture, industry, social and monetary affairs of country’s economy. .
More than 150 cotton hybrids have been released by various State Agricultural Universities and private seed companies.
Distant hybridization
Distant hybridization involves crossing individuals from different plant species or genera. It has been used to transfer desirable traits like disease resistance between crops. Some key challenges include hybrid sterility and incompatible crosses due to genetic differences between parental species. Techniques like embryo rescue and colchicine treatment have helped produce new crops through wide crosses, such as Nerica rice and triticale wheat-rye hybrids. Distant hybridization remains limited by barriers like hybrid breakdown but has achieved successes in improving crop varieties.
19. inbred lines development
1. Inbred lines are developed through repeated self-pollination or inbreeding of plants over multiple generations to produce genotypes that are homozygous and genetically uniform.
2. The pedigree method is most commonly used to develop maize inbred lines, involving self-pollination over 6-7 generations with selection of desirable plants each generation.
3. Doubled haploid lines can also be used, in which haploid cells are induced and then chromosome doubled to instantly produce completely homozygous lines.
Nature and components of variability
Types and components of variation, phenotypic, genotypic and environmental variation, additive , dominance and epistatic variance
Biparental mating design
Best of presentation prepared for better understanding of biparental mating design under the guidance of Dr. S.K. Singh.
Concept of combining ability
IN detailed explanation about combining ability, SCA, GCA, formulas to derive GCA and SCA, significance, examples to explain, case studies.
Apomixis
A game changer in plant breeding
,powerful breeding tool ,genetics ,asexual reproduction ,apomixis technology ,food ,agriculture research ,agriculture ,apomixis
What's hot (20)
Genetical and physiological basis of heterosis and inbreeding
Genetical and physiological basis of heterosis and inbreeding
Molecular Breeding in Plants is an introduction to the fundamental techniques...
Molecular Breeding in Plants is an introduction to the fundamental techniques...
Balanced tertiary trismoics - Hybrid seed production
Balanced tertiary trismoics - Hybrid seed production
Similar to Maize evolution
Maize origin.pptx
This document discusses the genetics and evolution of maize. It presents several hypotheses for the origin of maize, including the tripartite hypothesis involving Tripsacum, the catastrophic sexual transmutation theory, and the teosinte hypothesis. The document argues that most geneticists now accept that maize was domesticated from a wild grass called teosinte (Zea mays ssp. parviglumis) based on evidence from chromosome studies, isoenzyme analysis, and the ability to produce fertile hybrids between maize and teosinte.
Evolutionary significance of tb1 locus in Maize
The document discusses the evolution and domestication of maize from its wild ancestor, teosinte. It describes three hypotheses for the origin of maize and provides evidence that teosinte is the wild progenitor. Maize was domesticated in Mexico from a form of teosinte called Balsas teosinte. Key differences between maize and teosinte involved increased apical dominance and changes to inflorescence in maize. The tb1 gene was identified as playing a major role in these differences, with the maize version expressed at higher levels and regulating branching. Studies showed selection led to overexpression of tb1 during domestication, transforming teosinte architecture into the maize plant of today.
The Archaic and Formative Periods of MesoamericaMichael Love.docx
The Archaic and Formative Periods of Mesoamerica
Michael Love
Note: this piece is an article that I’m preparing for the Cambridge Encyclopedia of World
Prehistory, edited by Colin Renfrew and Paul Bahn. It presents a very different perspective on
domestication, agriculture, and sedentism than the scenario found in your textbook. I, of course,
think that my synthesis of the data is much better, but your textbook gives the generally accepted
viewpoint. You can also note my points of disagreement with Jared Diamond. The dates in the
article are all calibrated radiocarbon dates; the presentation and your textbook both use
uncalibrated dates, so there are bound to be differences. The Cambridge Encyclopedia uses BCE
(before common era) and CE (common era) instead of BC/AD. I haven’t inserted the images into
this article, but most of the referenced items are found in the Powerpoint presentation.
Mesoamerica is one of the six or seven areas of the world where independent
domestication of plants and animals lead to the emergence of food production, and subsequently
civilization (Bellwood 2005; Smith 1998). Mesoamerica was once considered to have lagged
behind other regions of the world in agricultural origins, but evidence now places the beginnings
of food production soon after the onset of Holocene conditions. Similarly, the origins of
urbanism and state formation are now placed much earlier than would have been the case a
decade ago. Once thought to be hallmarks of the Classic Period (AD 250-900), both urban
settlements and state-level polities are now well attested before the end of the first millennium
BCE.
The time of first domestication and the development of social complexity are called the
Archaic and Formative periods. The Archaic begins with the onset of Holocene conditions about
10,000 years ago and continued up to the time of the adoption of pottery, ca 2000 BCE. The
Formative period (also called the Preclassic) succeeds the Archaic and ends at 250 CE. The
criteria for defining both periods have shifted in recent times, and the divisions have become
blurred. It was once thought that the joint appearance of agriculture, sedentism and pottery
defined the beginning of the Formative, but earlier placement of first domestication and
sedentism leaves only early pottery as the sole criterion. The end of the Formative period is also
very arbitrarily placed at 250 CE, as many traits previously used to define the succeeding Classic
period, including writing, calendrics and urbanism, were well attested in the Late Formative (400
BCE-250 CE).
The Archaic Period
The Archaic period was the time during which domestication, food production, and
sedentism developed from the preceding Paleo-Indian Period (Stark 1981). In contrast to the Old
World and South America, domesticated animals placed only a minor role in the development of
food production in Mesoamerica. Although domesticated mammals and birds including ...
Gmo Maize Essay
GMO maize has potential nutritional benefits for Kenya by allowing injection of nutrients like iron and carotene. This could help address Kenya's problem of malnutrition. GMO seeds have also been developed that are drought resistant and require less water. This could help smallholder farmers in dry regions improve crop yields. However, there are also concerns about the impacts of GMO crops on biodiversity, agriculture, and human health.
GENETICS REVIEWER.pdf
This document provides an overview of genetics and its history. It begins with definitions of genetics and discusses early understandings from prehistoric times through Aristotle. It then summarizes major developments like Mendel's experiments, Darwin's theory of evolution, the rediscovery of Mendel's work, and discoveries in the 20th century like DNA's structure. The document outlines molecular genetics concepts and concludes with the scope and applications of genetics like biotechnology, disease control, and conservation.
History of plant breeding
Thomas Fairchild was the first to create an artificial plant hybrid in 1717 between Sweet William and Carnation pink, called "Fairchild's Mule". Important developments in the pre-Mendelian era included domestication of major crops by 1000 BC, and the first description of the cell in 1665. The Mendelian era saw the rediscovery of Mendel's laws in 1900 and the development of the first commercial maize hybrid in 1917. The post-Mendelian era brought the discovery of cytoplasmic male sterility in rice in 1933 and transposable elements in 1950. Modern developments include the first transgenic plant in 1983, Bt cotton in 1987, and the Protection of Plant Varieties and Farmers'
The discovery of agriculture
This paper is written to question the wide spread belief among anthropologists that pre historic hunter gatherers knew about agriculture long before agriculture began to be practiced. The paper suggests gradually accumulating human knowledge led to the development of agriculture, rather than population pressure, favourable mutations or convenient climate all of which would have occurred at various times long before agriculture was developed without leading to the discovery of agriculture.
Maize Research Paper
Maize, also known as corn, originated in South America and the West Indies approximately 6000 years ago. It is a fast-growing, nutritious crop that produces two harvests per season. These attributes made maize a staple food for many American and Caribbean cultures. The Mayans, Incas, Aztecs, and Anasazi domesticated maize over centuries and it nourished their civilizations. Europeans brought maize back to Europe after encountering it in the Americas, spreading its cultivation.
Domestication of plants
Corn was domesticated between 6,000-10,000 years ago from its wild ancestor, teosinte. Teosinte had hard shells enclosing its seeds and grew on spikes that shattered to disperse seeds, while domesticated corn develops hundreds of exposed kernels on cobs covered by husks. Archaeological and genetic evidence indicates corn was domesticated in southern Mexico. Other key domesticated grain crops discussed include rice, which originated in China around 8,200-13,500 years ago, beans which Native Americans began cultivating 7,000 BC, and wheat which has been cultivated for over 10,000 years beginning in the Middle East.
domestication of plants11111111111111111.pptx
Corn was domesticated between 6,000-10,000 years ago in southern Mexico from its wild ancestor, teosinte. Teosinte had hard shells enclosing its seeds and grew on spikes but corn has hundreds of exposed kernels on cobs covered in husks. There are different varieties of corn including dent, flint, popcorn. Rice was first domesticated 8,200-13,500 years ago in China but spread to Asia. Beans have been cultivated for over 7,000 years in Mexico and Peru and wheat was one of the first grains domesticated 10,000 years ago and was crucial to the development of communities and civilization.
Crop Domestication Lecture
Crop domestication began as early as 11,000 BC with rye and continued with many important food crops like wheat, peas, and fruit trees in the following millennia. Key traits selected by early farmers included decreased plant size, loss of seed dormancy, and increased seed/fruit quality and quantity. Many major crops like corn, potatoes, and tomatoes have their origins in Central and South America but were dispersed and further domesticated worldwide. The integration of crops with new environments and the introduction of techniques like selection and breeding have led to dramatic increases in yield, quality, and other beneficial traits in crops over thousands of years of human intervention and cultivation.
Sbc174 evolution 2014 week2
First year SBC174 Evolution course - week 2
1. NeoDarwinism/ModernSynthesis
2. Major transitions in Evolution
3. Geological Timescales
4. Some drivers of evolution
Plant breeding - History, Objectives & Activities
Discussion is about the detailed history of plant breeding, various objectives of plant breeding and activities of plant breeding. All topics are discussed to the point.
Plants domestication
Plant domestication began around 10,000 years ago in Mesopotamia when early humans began artificially selecting traits in wild plants like wheat and barley. Two key areas for early domestication were the Balsas River valley in Mexico, where corn was first domesticated from teosinte, and the Yangtze River valley in China, where Asian rice originated. Plant domestication allowed nomadic humans to settle into agrarian societies and led to the development of early civilizations dependent on domesticated crops like wheat, rice, beans, and potatoes.
KSKL chapter 8 PPT
Soils are essential to supporting life and human civilization. As populations grow, pressures on soils increase and maintaining soil health is important. Throughout history, human activities like deforestation, overgrazing, and poor irrigation have led to soil degradation problems like erosion, desertification, and salinization. This has negatively impacted societies by reducing agricultural productivity and sometimes causing civilizations to fail. However, more recent initiatives show people rediscovering the importance of soils and taking steps to promote sustainable land use and soil conservation.
Pertemuan 1. history of genetics
1. Genetics has a long history dating back to early animal and plant domestication where selective breeding was used to develop desirable traits.
2. Modern genetics was established in the mid-19th century through Mendel's work on inheritance in pea plants. Major advances in the 20th century included discovering that genes are located on chromosomes and determining the DNA structure.
3. Recent milestones include cloning DNA molecules and sequencing entire genomes, advancing basic research and medical applications. New techniques also raise ethical issues requiring consideration.
Development of Agriculture in Early Mesoamerican Societies
This document discusses the development of early agriculture in Mesoamerican societies. It focuses on evidence of plant domestication and agricultural strategies from an Early Archaic site in the Valley of Oaxaca, Mexico representing over 10,000 years of human occupation. The document examines how changes in climate around 10,000-8,000 BC affected subsistence patterns and led humans to begin cultivating plants like maize and domesticating crops. It also analyzes how early cultivation and cooperation among groups in places like Guila Naquitz cave led to more permanent settlements and complex societies centered around agriculture by the Late Archaic period in Mesoamerica.
Privacy in a Collaborative Environment
Privacy is an important consideration for collaborative genealogy platforms like Geni. Geni aims to balance privacy for living individuals and those with close relatives while also enabling collaborative research on distant ancestors. It allows users to maintain private family trees for close relatives but profiles become public once they reach beyond third great-grandparents to facilitate collaborative research. Geni has built the largest online genealogy database through the work of hundreds of thousands of volunteers contributing to a single World Family Tree.
History of Biotechnology
The document outlines the history of plant tissue culture from 1832 to the present. Some of the key events include Theodor Schwann presenting the idea that cells can grow outside the body in 1832. In 1898, Gottlieb Haberlandt made the first attempt at plant tissue culture but cells did not divide. Later researchers like White and Skoog added growth hormones like auxin and vitamins, enabling cell division. Techniques like cell suspension cultures and protoplast isolation were developed in the 1950s-60s, allowing for mass plant cell production. Somatic embryogenesis and regeneration methods enabled cloning in the 1970s. Today, tissue culture is used commercially and allows for disease-free propagation of plants.
study_soil.pptx
This document discusses the complexity of soil and the abundant life within it. It makes three main points:
1) Soil is a 3D habitat that varies in properties over space and time and supports a diverse ecosystem. It contains more organisms per gram than anywhere else, mostly microbes.
2) Abundant and diverse microbes and other organisms inhabit soil, including bacteria, fungi, protists, and more. A single hectare of topsoil contains biomass equivalent to 3 African elephants.
3) Soil organisms perform essential functions like decomposition, nutrient cycling, carbon storage, and soil structure, which all contribute to ecosystem health and support life above ground. Activities are suggested to explore soil biology.
Similar to Maize evolution (20)
The Archaic and Formative Periods of MesoamericaMichael Love.docx
The Archaic and Formative Periods of MesoamericaMichael Love.docx
Development of Agriculture in Early Mesoamerican Societies
Development of Agriculture in Early Mesoamerican Societies
Recently uploaded
South African Journal of Science: Writing with integrity workshop (2024)
South African Journal of Science: Writing with integrity workshop (2024)Academy of Science of South Africa
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.Executive Directors Chat Leveraging AI for Diversity, Equity, and Inclusion
Let’s explore the intersection of technology and equity in the final session of our DEI series. Discover how AI tools, like ChatGPT, can be used to support and enhance your nonprofit's DEI initiatives. Participants will gain insights into practical AI applications and get tips for leveraging technology to advance their DEI goals.
How to Build a Module in Odoo 17 Using the Scaffold Method
Odoo provides an option for creating a module by using a single line command. By using this command the user can make a whole structure of a module. It is very easy for a beginner to make a module. There is no need to make each file manually. This slide will show how to create a module using the scaffold method.
How to Manage Your Lost Opportunities in Odoo 17 CRM
Odoo 17 CRM allows us to track why we lose sales opportunities with "Lost Reasons." This helps analyze our sales process and identify areas for improvement. Here's how to configure lost reasons in Odoo 17 CRM
DRUGS AND ITS classification slide share
Any substance (other than food) that is used to prevent, diagnose, treat, or relieve symptoms of a
disease or abnormal condition
ANATOMY AND BIOMECHANICS OF HIP JOINT.pdf
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar KanvariaCACJapan - GROUP Presentation 1- Wk 4.pdf
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
বাংলাদেশ অর্থনৈতিক সমীক্ষা (Economic Review) ২০২৪ UJS App.pdf
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
Introduction to AI for Nonprofits with Tapp Network
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
Main Java[All of the Base Concepts}.docx
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
A Survey of Techniques for Maximizing LLM Performance.pptx
A Survey of Techniques for Maximizing LLM Performance
Types of Herbal Cosmetics its standardization.
Physiology and chemistry of skin and pigmentation, hairs, scalp, lips and nail, Cleansing cream, Lotions, Face powders, Face packs, Lipsticks, Bath products, soaps and baby product,
Preparation and standardization of the following : Tonic, Bleaches, Dentifrices and Mouth washes & Tooth Pastes, Cosmetics for Nails.
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
Chapter 4 - Islamic Financial Institutions in Malaysia.pptxMohd Adib Abd Muin, Senior Lecturer at Universiti Utara Malaysia
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
Denis is a dynamic and results-driven Chief Information Officer (CIO) with a distinguished career spanning information systems analysis and technical project management. With a proven track record of spearheading the design and delivery of cutting-edge Information Management solutions, he has consistently elevated business operations, streamlined reporting functions, and maximized process efficiency.
Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
-------------------------------------------------------------------------------
Find out more about ISO training and certification services
Training: ISO/IEC 27001 Information Security Management System - EN | PECB
ISO/IEC 42001 Artificial Intelligence Management System - EN | PECB
General Data Protection Regulation (GDPR) - Training Courses - EN | PECB
Webinars: https://pecb.com/webinars
Article: https://pecb.com/article
-------------------------------------------------------------------------------
For more information about PECB:
Website: https://pecb.com/
LinkedIn: https://www.linkedin.com/company/pecb/
Facebook: https://www.facebook.com/PECBInternational/
Slideshare: http://www.slideshare.net/PECBCERTIFICATION
Recently uploaded (20)
South African Journal of Science: Writing with integrity workshop (2024)
South African Journal of Science: Writing with integrity workshop (2024)
Executive Directors Chat Leveraging AI for Diversity, Equity, and Inclusion
Executive Directors Chat Leveraging AI for Diversity, Equity, and Inclusion
How to Build a Module in Odoo 17 Using the Scaffold Method
How to Build a Module in Odoo 17 Using the Scaffold Method
How to Manage Your Lost Opportunities in Odoo 17 CRM
How to Manage Your Lost Opportunities in Odoo 17 CRM
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...
বাংলাদেশ অর্থনৈতিক সমীক্ষা (Economic Review) ২০২৪ UJS App.pdf
বাংলাদেশ অর্থনৈতিক সমীক্ষা (Economic Review) ২০২৪ UJS App.pdf
Introduction to AI for Nonprofits with Tapp Network
Introduction to AI for Nonprofits with Tapp Network
A Survey of Techniques for Maximizing LLM Performance.pptx
A Survey of Techniques for Maximizing LLM Performance.pptx
Liberal Approach to the Study of Indian Politics.pdf
Liberal Approach to the Study of Indian Politics.pdf
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
Chapter 4 - Islamic Financial Institutions in Malaysia.pptx
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
ISO/IEC 27001, ISO/IEC 42001, and GDPR: Best Practices for Implementation and...
Maize evolution
- 1. MAIZE B.MOHANAPRIYA 2017600808 The Mayan corn god A successful domestication or a lucky accident
- 2. Ancient Maize • Origin: south central Mexico • Archeological remains of the earliest maize cob, found at Guila Naquitz in the Oaxaca Valley of Mexico (6250 years ago). • Microfossil evidence suggesting dispersal by 7,000 – 5,000 BP • Estimation of domestication of maize: 12,000-6,000 BP From “The emergence of Agriculture” by Bruce D. Smith, 1995 http://en.wikipedia.org/wiki/Image:Mesoamerica_english.PNG
- 3. Where does the the corn comes from …..?
- 4. • Unlike most crops, maize does not have a morphological equivalent wild form. Particularly, maize has no wild relative having a cob-like pistillate inflorescence (ear). • Interpreting the relation between maize and its wild relative generated a big debate over the 20th century. http://www.gramene.org/zea/maize_anatomy_and_taxonomy.html
- 5. Origin of Maize: three hypothesis • Tripartite hypothesis • Teosinte hypothesis • Recombination hypothesis www.maizemap.org
- 7. Counter arguments • Differences in chromosome number and constitution between Zea (10 chromosomes) and Tripsacum (18 or 36 chromosomes). • Basing their assumption on a “missing wild maize”
- 9. First empirical demonstration of how teosinte could have been transformed into maize via Tripsacum introgression. Hybrids show intermediate form: have partially fused rachis, 2 kernel per rachis (instead of 1) and the kernels are partially exposed at the tips From Darwin’s harvest 2006
- 10. Counter arguements • 23% of the molecular markers are not found in either progenitor 120 point mutations/gene (3 million times the normal rate of mutation: 6 x 10-9 substitutions per site per year) • Only 1 sp of Z.m ssp parviglumis included
- 11. Teosinte hypothesis • Ancient people cultivated teosinte because it provided a useful food source • During cultivation, mutations that improved teosinte’s usefulness to humans arose and were selected • As few as 5 major mutations would be sufficient to convert teosinte in a primitive form of maize • Over the course of time, humans selected additional major mutations plus many minor ones As stated by Beadle (1939)
- 19. Genetics of maize evolution, J. Doebley 2004 (www.BioInteractive.org ) tga1 (teosinte glume architecture 1) dvt of glume lacking in maize present in teosinte (forms the cupule)
- 21. Genetics of maize evolution, J. Doebley 2004
- 22. Genetics of maize evolution, J. Doebley 2004 tb1: (teosinte branched1) dictates difference in plant architecture (long lateral branches terminated by male tassels in teosinte vs short lateral branches tipped by female ears in maize)
- 25. Genes under current investigation • shattering vs solid cobs • single vs paired spikelets • distichous vs polystichous condition
- 27. Modern Argument • With more molecular analysis and archaeological findings, teosinte appears to be sufficiently similar on a genetic level to maize: – Cytological evidence: same chromosome numbers, complete chromosome pairing, full fertility (Emerson & Beadle 1932) . Chromosome arm length, centromere position, sizes in annual teosintes are identical to those in maize (Longley 1941). Longley (1941) & Kato (1976) later suggested that from all teosintes, mexican were the more similar to maize.
- 28. – Evidence at the protein level: classification of teosinte populations based on isozyme allele frequencies. It allowed to pinpoint the mexican teosinte that had allele frequencies “essentially indistinguishable” from maize: Z. mays ssp parviglumis. (Doebley et al 1984). – Evidence at the molecular level: a study of the microsatelite diversity in maize and teosinte (Matsuoka 2002) confirmed the isozyme results. They also demonstrated a single domestication event, and that Balsas teosinte diverged. Jaenicke-Despres (2003): ancient DNA studies support that teosinte was rapidly transformed into maize around 9000-7000 years ago.
- 29. THANK YOU