Download Methods to improve seeds

Methods to improve seeds
1. Selection – take individual plants and
pick the best plants from them and
plant their seeds.
2. Directed Breeding – cross two plants
together in order to get hybrid vigor to
better the crop.
3. Gene Splicing – slicing out a section
of a plant and putting it into a totally
different plant. GMO’s
How is this breeding
accomplished?
In the chromosomes the genetic
characterists are contained in genes.
And they produce enzymes which
produce protein. These proteins have
an effect on DNA and RNA.
Terms
1. Genotype – Genetic make up of the plant.
Not always visible.
2. Phenotype – Physical make up of the gene
combinations. What you can see.
3. Sexual Reproduction – Gametes
Diploid (2n) pair of chromosomes
Haploid (1n) a single chromosome
4. Alleles – same location on a gene of
a chromosome.
5. Homozygous – same gametes.
6. Heterozygous – different gamets.
7. Dominate trait – mask another.
8. Recessive trait – only seen when
paired together.
9. Recessive trait – only seen when
paired together
10. Mitosis – Cell division, making
diploid cells , normal growth,
daughter cells the same as the
parent cell.
11. Meiosis – sexual reproduction
through division.
12. Pollination – the transfer,
movement, of pollen grains from the
anther to the stigma.
13. Hybrid – is an offspring of a cross of
two different genetic parents of the
same species.
+’s Highly uniform, increased vigor,
increased yields, very
predictable.
-’s Can’t reuse seed, expensive,
more locally adapted, may or may not
have as much disease res. As O.P.’s
Flowers
1. Contain organs for specialized
sexual production
2. Produce seeds and fruit
Parts of the Flower
Sepals
Outer covering of the flower bud
Protects the stamens and pistils when
flower is in bud stage
Parts of the Flower
Petals
Brightly colored
Protects stamen and pistils
Attracts pollinating insects
Parts of the Flower
Stamens
Male Reproductive part
Anther-produces pollen
Filament-supports the anther
Parts of the Flower
Pistil
Female reproductive part
Ovary
Enlarged portion at base of pistil
Produces ovules which develop into seeds
Stigma
Holds the pollen grains
Parts of the Flower
Style
Connects the stigma with ovary
Supports the stigma so that it can be
pollinated
Complete and Incomplete
Flowers
Complete: have all four main parts
Sepals
Petals
Stamens
Pistils
Some plants have both male &
female flowers
1. Monoecious – plants contain both
male and female flowers.
2. Dioecious – plants contain only one
sex and another plant contains
counter part. Male plants and
female plants.
3. Gynecious – only female and very
few male flowers.
4. Andromonecious – only male and
very few female flowerws.
Methods of pollination
1. Self Pollination – Pollinates
themselves.
2. Cross Pollination – due to wind,
animals, or insects plants pollinated by
other plants.
Plant Improvements, How
does man manipulate plants?
1. Render the pollen non-viable
Male sterility
Emasculation – remove or kill anther.
2. Selection – A process in which you
pick certain plants to reproduce.
3. Rouging – to pick out a few plants
and cull them out and keep the
remaining plants.
4. Mass Selection – take a sample from
a population and grow it for seed
production.
Heterosis (Hybrid Vigor) - cross two
plants and get an offspring that will be
superior to its parents.
Inbreeding Depression – the vigor of
that crop goes down dramatically.
To get a select line – you must isolate
the crop so they can’t pollinate by any
other crop. Also put up cages to keep
insects out. Cover stigmas with bags.
Hybrid – is an offspring of a cross of to
different genetic parents of the same
species.
+’s = Highly uniform, very predictable,
vigor increases, yield increases
-’s = Can’t reuse seed, expensive,
more locally adapted, may or may not
have as much disease resist. as O.P.
Vegetative propagation
Examples of plants –
Garlic
Rhubarb
Artichokes
Potato
Sweet Potato