Clone is the progeny of a single plant, produced by asexual reproduction
Clonal selection is the selection of the most desirable members of a clone for continued vegetative propagation rather than for sexual reproduction.
The members of a clone keep up genetic constancy.
So by clonal selection and continued vegetative propagation, the desirable qualities of plants can be maintained for long.
The mating or crossing of two plants or lines of dissimilar genotype is known as hybridization. The chief objective of hybridization is to create genetic variation, when two genotypically different plants are brought together in F1. Here, we are going to discuss about different strategies and tools used for hybridization.
Mutagenesis is the process by which the genetic information
of an organism is changed in a stable manner.
The term ‘mutation breeding’ has become popular as it
draws attention to deliberate efforts of breeders and
the specific techniques they have used in creating and
harnessing desired variation in developing elite breeding
lines and cultivated varieties.
Plant breeding methods of vegetatively propagated crops Roksana Aftab Ruhi
Vegetatively propagated crops are bred by intentionally crossing of closely or distantly related individual to produce new crop varieties or lines with desirable traits. Breeding of vegetative crops have successfully improved quality, yield, tolerance of crops to environmental pressure. Breeding helps in producing crops that are resistant to viruses, fungi and bacteria and helps in longer storage period for the harvested crop.
Self-incompatibility refers to the inability of a plant with functional pollen to set seeds when self pollinated. It is the failure of pollen from a flower to fertilize the same flower or other flowers of the same plant.
This presentation includes, Single-locus self-incompatibility- {Gametophytic self-incompatibility (GSI) and Sporophytic self-incompatibility (SSI)},2-locus gametophytic self-incompatibility, Heteromorphic self-incompatibility,Cryptic self-incompatibility (CSI) and Late-acting self-incompatibility (LSI).
Clone is the progeny of a single plant, produced by asexual reproduction
Clonal selection is the selection of the most desirable members of a clone for continued vegetative propagation rather than for sexual reproduction.
The members of a clone keep up genetic constancy.
So by clonal selection and continued vegetative propagation, the desirable qualities of plants can be maintained for long.
The mating or crossing of two plants or lines of dissimilar genotype is known as hybridization. The chief objective of hybridization is to create genetic variation, when two genotypically different plants are brought together in F1. Here, we are going to discuss about different strategies and tools used for hybridization.
Mutagenesis is the process by which the genetic information
of an organism is changed in a stable manner.
The term ‘mutation breeding’ has become popular as it
draws attention to deliberate efforts of breeders and
the specific techniques they have used in creating and
harnessing desired variation in developing elite breeding
lines and cultivated varieties.
Plant breeding methods of vegetatively propagated crops Roksana Aftab Ruhi
Vegetatively propagated crops are bred by intentionally crossing of closely or distantly related individual to produce new crop varieties or lines with desirable traits. Breeding of vegetative crops have successfully improved quality, yield, tolerance of crops to environmental pressure. Breeding helps in producing crops that are resistant to viruses, fungi and bacteria and helps in longer storage period for the harvested crop.
Self-incompatibility refers to the inability of a plant with functional pollen to set seeds when self pollinated. It is the failure of pollen from a flower to fertilize the same flower or other flowers of the same plant.
This presentation includes, Single-locus self-incompatibility- {Gametophytic self-incompatibility (GSI) and Sporophytic self-incompatibility (SSI)},2-locus gametophytic self-incompatibility, Heteromorphic self-incompatibility,Cryptic self-incompatibility (CSI) and Late-acting self-incompatibility (LSI).
SELECTION METHODS IN SELF-POLLINATED CROPS viz., mass selection, pureline sel...AMIT RANA Ph. D Scholar
MASS SELECTION
Mass selection is a method of breeding in which individual plants are selected on the basis of phenotype from a mixed population , their seeds are bulked and used to grow the next generation.
Selection cycle may be repeated one or more times to increase the frequency of favorable alleles - phenotypic recurrent selection.
PURELINE SELECTION
A pureline is the progeny of a single homozygous plant of a self-pollinated species. All the plants in a pureline have the same genotype and the phenotypic variation within a pureline is due to the environment alone and has no genetic basis. However, variation within a pureline is not heritable. Hence selection in a pureline is not effective. Johannsen (1903,1926), a Danish biologist, developed the concept of pureline theory working with Princess variety of French bean (Phaseolus vulgaris), which showed variation for seed size. From a commercial seed lot he selected seeds of different sizes and grew them separately. The progenies differed in seed size. Progenies from larger seeds produced larger seeds than those obtained from smaller seeds. This clearly showed that the variation in seed size in the commercial seed lot of princess variety had a genetic base. As a result selection for seed size was effective.
Introduction
PEDIGREE SELECTION
Pedigree selection is a widely used method of breeding self-pollinated species.
A key difference between pedigree selection and mass selection or pure-line selection is that hybridization is used to generate variability (for the base population), unlike the other methods in which production of genetic variation is not a feature.
The method was first described by H. H. Lowe in 1927.
Pedigree selection is a breeding method in which the breeder keeps records of the ancestry of the cultivar.
The base population is established by crossing selected parents, followed by handling an actively segregating population.
Documentation of the pedigree enables breeders to trace parent–progeny back to an individual F2 plant from any subsequent generation.
The breeder should develop an effective, easy to maintain system of record keeping.
Pedigree selection is applicable to breeding species that allow individual plants to be observed, described, and harvested separately.
Clone is the progeny of a single plant, produced by asexual reproduction
Clonal selection is the selection of the most desirable members of a clone for continued vegetative propagation rather than for sexual reproduction.
The members of a clone keep up genetic constancy.
So by clonal selection and continued vegetative propagation, the desirable qualities of plants can be maintained for long.
Seminar of U.V. Spectroscopy by SAMIR PANDASAMIR PANDA
Spectroscopy is a branch of science dealing the study of interaction of electromagnetic radiation with matter.
Ultraviolet-visible spectroscopy refers to absorption spectroscopy or reflect spectroscopy in the UV-VIS spectral region.
Ultraviolet-visible spectroscopy is an analytical method that can measure the amount of light received by the analyte.
This pdf is about the Schizophrenia.
For more details visit on YouTube; @SELF-EXPLANATORY;
https://www.youtube.com/channel/UCAiarMZDNhe1A3Rnpr_WkzA/videos
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Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Richard's entangled aventures in wonderlandRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
2. Selection is the choosing of the best variety
It can be natural or artificial
Natural selection – selection which occur naturally
Artificial selection – done by man made
Important method in plant breeding
Practiced in both homozygous and heterozygous population
Effectiveness of selection depend on genetic variability of the base population &
hereditary
NATURAL SELECTION
It is a natural process
It operate without human interference
According to the Darwin's principal “ survival of the fittest “ , plant which
survive through the adverse condition are preferred and the weekend one are
wiped out .thus nature select the fittest organism
3. ARTIFICAL SELECTION
Here selection agent is man
Man select better variety from mixed population and try to propagate them
Four method :
A. Mass selection
B. Progeny selection
C. Pure line selection
D. Clonal selection
A. MASS SELECTION
In mass selection plant are selected from a mixed population on the basis of
their phenotype
Applicable to both self and cross pollinated species
4. Selection done for easily observable character – plant height ,grain size ,grain
colour , disease resistance
Plant are selected on the basis – phenotype
The population obtained from the selected plants – uniform than the original
plants
Two type :
Negative mass selection – cutting out of all poorly developed ,less productive
inferior plant and remaining superior part are propagated
Positive mass selection – only plant with desirable trait are propagated
several plants are selected seeds are mixed
So, the selected population would be the mixture of several similar looking pure
lines
Variety developed through mass selection would have considerable genetic
variation
5.
6. MERIT
Simplest , easiest and quickest method of crop improvement
No need of scientific knowledge
Pollination do not required for producing new variety
Applicable for both self and cross pollinated spieces
Provide disease resistance crop
They are more stable
DEMERIT
Selection based on phenotype
In cross pollinated crop , large no: of plant have to be selected for propagation ,
small sample will lead to the inbreeding depression
Not applicable to self pollinated speices
Importance given to character only
7. ACHEIVEMENTS
Mass selection was extensively used by farmers and agriculturalist for the
improvement of self pollinated crop before pure line selection came into
practice
Mass selection is routinely practice to maintain purity of pure line variety
In india it is used in the development of improved varieties of cross pollinated
crop like maize , pearl millet and mustard
B.PROGENY SELECTION
commonly used in cross pollinated crop
Progeny selection can be defined as new individual organism that result from
the process of sexual and asexual reproduction
This method extensively used in maize
8. MERIT
method is simple and convenient
Method more effective than mass selection because selection based on progeny
not on phenotype
Inbreeding may be avoided if sufficient large number of progeny are selected
DEMERIT
If the progeny of each plant is tested ,it would required large area which is not
practically possible
C.PURE LINE SELECTION
Also known as individual plant selection
In pure line selection a large no : of plants are selected from a self pollinated
crop and are harvested individually hence it is known as individual plant
selection
9. Through pure line selection we can obtain single , homozygous , self pollinated
plant
It has identical genotype
It is non heritable
Pure line selection procedure :
A. Selection of individual plant from a local variety
B. Visual evaluation of individual plant
C. Yield trails
D. Disease resistance and quality test are done
E. Best progeny release a new variety
F. Seed multiplication
G. Distribution
MERIT
High yield
10. Disease and insect resistance
The variety developed by this method is uniform and more attractive than mass
selection
Easy method
Expensive is very low
Easier than hybridization
DEMERIT
It is very lengthy
Heavy laboratory process
Applicable only to self pollinated crop
It cannot develop new genotype
Adaptability to new environment condition is poor
11.
12. ACHEIVEMENTS
Wheat –NP4 , NP6 , NP12
Rice - CO19 CO5 APS1
Cotton – KC1
Cabbage – pusa drum head
Onion – pusa read punjal
Papaya - CO1 , CO5
Guava – arka mridula
D.CLONAL SELECTION
A clone is a group of plant produced from a single plant through asexual
reproduction
Selection of desirable clone from the mixed population is known as clonal
selection
13. Asexual reproduction avoid segregation and recombination
Progeny are identical to their parent
All clones are genotipicaly and phenotipicaly similar
Clones are stable as pure lines
Procedure :
A. Clones are selected from mixed population
B. Selected plants are asexually propagated
C. Seed multiplication
D. Evaluation of seed for 3- 4 years
E. Thus release of a new variety
This method take 9 -10 years
MERIT
It is only method to improve the clonal crop
Clonal propagated variety are highly stable
14. Hybrid vigor is easily utilized
It is also help to eliminate unproductive and undesirable types
DEMERIT
In this method no genetic variability can be created
This method only applicable to vegetatively propagated crops
ACHIEVEMENTS
Potato – kufrl red
Cavendish – bombay green
Mango – niranjan
Banana – high rate
Tapioca – CO1
Rose – edward rose , andhra rose