Lec 4 Flashcards
(34 cards)
What is SALB?
south American leaf blight
the limiter of rubber production
How old are rubber toys?
Go back to the 1400s
Where was rubber first supplied from?
Brazil
What is fordlandia?
Rubber plantation of 3500 ha monoculture style
Where was SALB most prevalent?
Around the equator in tropical areas
What is propagation?
breeding plants naturally
What are examples of propagation?
- Budding (grafts)
- seeds
- cuttings from young trees
- air layering
- tissue culture
What is Hevea Brasiliensis
Rubber tree
When are leaves susceptible?
When they are young
Why would grafting be beneficial?
to adopt traits in order to create the most optimal plant
What is the role of rubber in plants?
- rubber containing latex plays a role in disease resistance, wound healing or tolerance to stress
- anti-fungal and coagulant proteins
- prevents herbivory and traps insects
- prevents damage to photosynthetic apparatus under conditions of cold temp and high light
What is phloem?
conducting vessel
Do latex vessels run clockwise or counterclockwise from vertical
counter-clockwise
What percentage of latex in rubber trees is rubber?
30%
What does latex consist of?
gums, proteins, sugars, oils, salts, alkaloidal drugs, enzymes, and other substances
How old do rubber trees need to be before tapping?
5-8
How to tap a rubber tree?
- Tap 3 times per week for 6 months then give a 3 month break
- hormones and herbicides to stimulate flow
- flow for 1-4 hrs
- anticoagulant in cup
What is another source of latex rubber?
milk weed and dandelions
Synthetic rubber characteristics?
Weak, less elastic, conducts heat less well, non-renewable, not as weather-bearing
What are signs of SALB?
Grey/green spots under leaves
- necrosis
- young first
- lesions on stem
- death of tree
What is pseudocercospora ulei?
the pathogen that is SALB
What is perithecia?
infective ascospores secual
What are conidia?
Infective asexual spores
What is Pycnidiospores?
Not infective
