A modern approach for plant disease management - plant biotechnology

1. PRESENTER-RASHMI M G
1ST YEAR MSc. BOTANY
MAHARANI’S SCIENCE COLLEGE FOR
WOMEN
MYSORE

2. According to Horsefall and Dimond (1959) the disease :-
 Is not a pathogen
 It is caused by a pathogen
 Is not the symptoms or effects seen on the plant, symptoms
result from disease
 Is not a condition as the condition results from the disease
 Is not any injury which results from disease as well as from
any traumatic cause
 Cannot be catching or infectious, it is actually the pathogen
which is catching or transmitted
They define disease as a malfunctioning process in thee plant
body due to continuous irritation which results in some
suffering
It is the pathological process in plants and animals

3.  The branch of science that deals with the study of nature,
development and control of plat diseases is known as
phytopathology
 The phytopathology has 4 main objectives-
 Etiology-concerns with causal organisms along with
environmental conditions that cause diseases in plant
 Pathogenesis- actual mechanism of disease development and
involves complex host-pathogen interactions
 Epidemiology- concerns the interaction of crop, pathogen and
environment, the seasonal carryover and subsequent
dispersal of pathogens
 Control – concerns with the development of suitable methods
of controlling the diseases
 Fungi, bacteria, viruses, algae, nematodes, phanerogamic parasites and
unfavorable environmental conditions are the most important agents of
diseases in plants

4.  Generation of useful products or services
from plant cells, tissue and often from small
organ explants
 Such cells, tissues and organs are either
continuously maintained in vitro or they pass
through variable phase to enable
regeneration from them of complete plants,
which are ultimately transferred to the field
 Therefore plant tissue culture forms an
integral part of any plant biotechnology
activities

5. The various objectives of plant biotechnology are –
1. Useful biochemical production
2. Rapid clonal multiplication(adventitious shoot/bulbs, axillary bud
proliferations)
3. Virus elimination (thermo-, cryo - , chemotherapy coupled with
meristem culture)
4. Rapid development of homozygous lines by producing haploids
(anther culture, ovary culture, interspecific hybridization)
5. Production / recovery of difficult to produce hybrids(embryo rescue,
in vitro pollination )
6. Germplasm conservation of vegetatively reproducing plants or
those producing recalcitrant seeds( cryopreservation, slow growth
cultures, DNA clones)
7. Genetic modification of plants (somaclonal variation, somatic
hybridization, cybridization and gene transfer)
8. Creation of genome maps and use of molecular markers to assist
conventional breeding efforts

6.  Propagation or multiplication of heterozygous
genotypes is, of necessity, by vegetative propagation
as it involves only mitotic cell division.
 Progeny obtained by vegetative propagation(or
asexual reproduction) of a single plant or individual
constitute a clone
 Vegetative reproduction is achieved is achieved by
cutting, budding, grafting etc.
 Tissue culture also enables rapid clonal propagation of
plants this is also called MICROPROPAGATION
 Ex. This method is used for commercial production of
mainly ornamental plants and fruit trees such as
banana

7. Selection of an elite
mother plant
Explant
Surface sterilization and
washing
Establishment of growth
medium
Transfer to proliferation
medium
Shoot or embryo
formation
Transfer of shoots /
plantlets to sterilized soil
or artificial medium by
various gradual weaning
process
Stages of
Micro
Propagation

9. 1. It is helpful with regard to crop improvement
2. Extremely high multiplication ex. 106 plants per
year from single explant
3. Helps in bulking up rapidly new cultivars of
important trees
4. During micropropagation fungi, bacteria are
usually eliminated so that the plants obtained are
clean, while conventional methods propagate the
disease as well
5. Production of disease free plants- meristem
culture
6. Can be carried out throughout the year
independent of seasons

10.  It refers to an organism or a plant cell that has
been altered by the introduction of foreign DNA
sequences from another species
 This is done through recombinant DNA techniques,
which involves either the combining of DNA from
different genomes or the insertion of foreign DNA
into a genome
 Conventionally the genetic variation necessary for
crop improvement is generated through
hybridization, mutagenesis and polyploidy
 The genes from unrelated organism are called
transgenes and the plants containing transgenes
are known as transgenic plants

11. It has enabled mobilization of genes from
any plant or even synthetic DNA
sequences into the genome of any plant
species
1. Herbicide resistance
2. Insect resistance
3. Virus resistance
4. Fungal and bacterial disease resistance
5. Drought resistance
6. Seed protein quality

12. Isolation of gene of interest from
the source of organism
Insertion of transgenes into the Ti
plasmid
Introduction of T-DNA containing
–plasmid into agrobacterium
Attaching the bacterium to the
host cell

14. crop Gene transferred Insects controlled
Tomato Bt Heliothis armigera
Cotton Bt Cotton ball worm
Rice Corn cysteine gene Coleopteran
Maize Bt cry 11 European corn borer
Sugarcane Bt cry 1 Sugarcane borer

15. Crop Gene transferred Controlled pathogen
Rice Chitinase Rhizoconia solani
potato PR5 Phytophthora infestans
Carrot 1,3-β glucanase Alternaria dauci
Tobacco Lysozyme from human Pseudomonas syringae
Kiwi fruit 1,3-β glucanase Botrytis cinerea

16. 1. Specific genes have been transferred into
plants to improve their agronomic and
other features
2. Genes for resistance to various biotic
stresses have been engineered to
generate transgenic plants resistant to
insects, viruses, etc
3. Improves the quality of produce

17.  Plants are the key to life on earth as they directly supply 90%
of human calorie intake, and 80% of the protein intake
 Of the 3000 plant species which have been used as food by
man the world is now depends mainly on around twenty crop
species for the majority of its calorie
as the population continues to expand, the consumption rate
also increased and there is no other option other than
advancement of farming practices to get high yield therefore
people are reliable on these different biotechnological
practices for the crop improvement and to obtain disease free
crops for their survival
Reference
https://images.google.com/
Plant pathology –Dr. B P PANDEY
Introduction to plant biotechnology –H S CHAWLA