The Presentation is prepared by the N.S Institution of science, Markapur. It consists of a basic introduction related to Detection of Genetically modified plants and Organic Seed production.

2. Topic : Detection of Genetically modified plants and Organic Seed production
Course title : Principles of Seed technology
Course No : GPBR – 314
Submitted to : Submitted by :
Dr.V. Umesh Kumar NAA 18 - 65
Assistant Professor NAA 18- 66
Dept. of Genetics and plant breeding B.Sc(Hons)Agriculture
3rd Year 2nd sem

3. Genetically Modified Crops
• Genetically modified crops (GM crops) are plants used in agriculture, the
DNA of which has been modified using genetic engineering methods.
• Plant genomes can be engineered by physical methods or by use of
Agrobacterium for the delivery of sequences hosted in T-DNA binary
vectors.

4. It is important to differentiate that assessment of GMO content in
samples can be divided in three different levels:
1) Detection. The purpose of detection is to determine whether a sample contains GMOs.
For this objective, a screening method can be used resulting in a positive/negative statement.
The screening methods are usually based on the polymerase chain reaction (PCR).
2) Identification. If there is a positive detection of GMOs, further analysis is required to
discover which GMO it is and thus whether the GMO is approved within the EU. The only
analytical methods, which unequivocally may enable identification of each GMO variety are
methods based on PCR.
3) Quantification. If a product has been shown to contain GMO(s), the next step is to
assess compliance with the 1% threshold level (or the 0.3 or 0.5% level, respectively for
seeds) by the determination of the exact amount of each of the GMOs present in the sample.
Typically quantification is performed using semi- quantitative PCR or Real-time PCR. 8

5. GMO testing methods
Low technological methods
Phenotypic characterisation (herbicide assays)
Protein based methods
ELISA
Lateral Flow tests
High technological method
PCR 15

6. Polymeric Chain Reaction
• PCR (polymerase chain reaction) is the most widespread method for
identification of GMOs.
• PCR consists of extraction and purification of DNA, amplification of the
inserted DNA by PCR and confirmation of the amplified PCR product. In
principle, PCR can detect a single target molecule in a complex DNA
mixture
• PCR tests can be designed to detect any of the inserted genetic material:
promoter, structural gene, stop signal or marker gene.
• The exact design of any particular test depends on the requirements.
PCR can be used for a general screening of GMOs using primers that
recognise common DNA, which most GMOs harbour,

7. Procedure
• three major steps are involved in a PCR. These three steps are repeated for 30 or 40 cycles.
The cycles are done on an automated cycler, a device which rapidly heats and cools the test
tubes containing the reaction mixture.
• Each step –
1. Denatauration (alteration of structure)
2. Annealing (joining)
3. Extension -- takes place at a different temperature:

8. Denaturation: At 94 C (201.2 F), the double-stranded DNA melts and
opens into two pieces of single-stranded DNA.
Annealing: At medium temperatures, around 54 C (129.2 F), the
primers pair up (anneal) with the single-stranded "template" (The
template is the sequence of DNA to be copied.) On the small length of
double-stranded DNA (the joined primer and template), the
polymerase attaches and starts copying the template.
Extension: At 72 C (161.6 F), the polymerase works best, and DNA
building blocks complementary to the template are coupled to the
primer, making a double stranded DNA molecule.

10. Trans gene Contamination in Gm and Non Gm crops
• Genetic pollution is a controversial term for uncontrolled gene flow into wild populations.
• It is defined as "the dispersal of contaminated altered genes from genetically engineered
organisms to natural organisms, esp. by cross-pollination but has come to be used in some
broader ways.
• It is related to the population genetics concept of gene flow, and genetic rescue, which is
genetic material intentionally introduced to increase the fitness of a population It is called
genetic pollution when it negatively impacts on the fitness of a population, such as through
outbreeding depression and the introduction of unwanted phenotypes which can lead to
extinction.

11. • In the case of a transgene a novel gene is introduced into a given
genome and this may constitute some concern, as this transgene
can be transmitted to other organisms.
• Thus, the transgenic organism has not only novel traits whose
consequences should be carefully evaluated, but also the potential
to transmit this property to any sexually compatible plant.
• Recognizing this potential transgene flow, cultivation of GM crops
for research and commercial purposes have been performed under
some restriction to avoid the escape of a transgene

12. Organic Seed Production
Methodology
• Soil management
1. Plants need NPK, as well as micronutrients
2. Intercropping & Crop rotation and green manure
3. Organic farmers also use animal manure, certain processed fertilizers such as
seed meal and various mineral powders such as rock phosphate and greens
and, a naturally occurring form of potash which provides potassium

13. • Weed management •
1. Tillage •
2. Flame weeding and thermal weeding
3. Mulching
4. Naturally chemicals are allowed for herbicidal usecertain formulations of ac
etic acid corn gluten meal, and essential oils

14. • Controlling other organisms IPM practices biological pest control:
1. Beneficial insects include minute pirates bugs, big-eyed bugs, and to a lesser
extent ladybugs.
2. Naturally-derived insecticides :
Bacillusthuringiensis (a bacterial toxin), pyrethrum (a
chrysanthemum extract), neem (a tree extract) and rotenone (a legume root e
xtract) Compost tea contains a mix of beneficial microbes, which may attack or
out-compete certain plant pathogens

15. • Management of Weed Seeds in your Harvested Seed Lot •
1. avoiding weed seed contamination during the harvesting process
2. If the seed is even a slightly different size or weight, it may be removed with
standard seed cleaning practices such as screening or fanning.
3. Focus efforts on weed management and contamination prevention.
Marketable, but lower quality seed crop if contaminated with weed seed.
Noxious or prohibited weed seed.
4. Distinctly different size and/or weight from crop seed. Manage weeds and
prevent contamination, but if contaminated, remove in cleaning process.
Extra work to remove weed seed in cleaning process. Must take extra care to
ensure 100% of prohibited seed removed and noxious weed seed below
allowable level