Partial 2 Flashcards
What microorganisms are the most common to contamainate a culture?
Bacteria
How can you aradicate virus contaminaation in a cullture?
Meristem culture
Initiation contamination
The ones that are appreciable within a couple days
Latent contamination
Contamination that appears long after setting the culture. Usually bacteria probably inside the tissue that are not pathogenic to the plant in nature. It can be transferred to other cultures
Introduced contamination
Contamination exisiting due to poor practces or dirty equipment
Forms of sterelization
Heat, chemicals, irradiation, high pressure, filtration
Axenic culture
A culture media that has no microorganisms but only one organism living in it
Effects of contamination
Overgrowing and killing the organism
Microorganisms exhaust the media nutruents
Change in secondary metabolites
Common antibiotics in TC
Carbenicillin Cefotaxime Rifampicin Tetracycline Streptomycin
UV radiation for sterilization
254 nm
Flaming as sterelization
95% alcohol and fire
Autoclave conditions
15 psias 250 ºF/121 ºC, time depends on liquid volume
Filtration
When media has proteins, GA, IAA, proteins and antibiotics
What HEPA stands for
High Efficiency Particulate Air filters 99.97 % of particles above 0.3 microns
Convencional propagation
Cuttings
Buddings, grafting
Layering
Desirable properties of explants
Easily sterilizable
Juvenile
Responsive to culture
What is the most used explant?
Axilarry buds, >95%
Prone to genetic instability explant
Adventitious shoots formation
Axillary shoot proliferation
Growth of axillary buds proliferated with cytokinins
Axillary shoot proliferation procedure
Selection of plant material Stablish asceptic culture Multiplication Shoot elongation Root induction/formation Acclimatization
Four stations of micropropagation
Stage I: Introduction ans stablishment of aseptinc culture
Stage 2: Multiplication
Stage 3: Rooting and preparation
Stage 4: Acclimatization
Hormone indicuing somatic embryogenesis
A auxin: 2,4-D
Mother block
Slowly multiplied index and stabilized set of culture
Serve as a source of culture for stage 2
Of what kind of cells is made a callus?
Parenchymous cells
Callus medium
MS Media Auxin:Cytokinins 1:1 Sucrose 3% w/v pH: 5.6-6, optimum 5.8 Gelling agent
Callus Incubation characteristics
25 +-2ºC
Light: 5,000 - 10,000 lux/m
16 h light, 8 h dark
Where callus formation begins
In the outer layer of the cortical cells of the stem, forming pressuer and the being exposed
When is callus vitrification produced?
High relative humidity and presence of ethylene
Steps of indirect organogenesis
Induction: Aux:Cyt Proliferation/maintainance: Suspension Regeneration: Produce other organs Rooting Acclimatization
