About Bacteria
During the past couple of decades scientist have found million of different types of bacteria. The focus of this assignment is looking at bacteria that generally affect crops or just plant species in general. There are many, many bacteria that affect plant species some are Erwinia, Pectobacterium, Pantoea, Agrobacterium, Pseudomonas, and Ralstonia. The main focus is on the bacteria called Erwinia. These bacteria's are generally pod shaped and are related to E. Coli.
Threats
The Erwinia is a type of bacteria that causes fire blight on fruits such as Apples, Pears and other rosaceous crops. This is a very harmful infection in plants as this can swipe out an entire orchard in a single season. The sympotoms of this disease are clear in apples it causes them to turn black, small and crack making them seem like they've been burnt. The fire blight is most seen in pears. The fire blight infection in plants has been seen in many countries including Australia (reason why at times apples have to be exported from the UK to Australia.), USA and it's believed to be in Japan although authorities have denied it.
Prevention And Adaptation/Resistance
Preventive measures for the fire blight infection is using cooper spray to stop any new infections for occurring. When farm owners start using this cooper spray at first it may work but spraying it for many years increases the chances of having bacteria (Erwinia) with a more resistance to this spray this can reach heights where this copper spray would not have effect anymore. This happens because when this spray is used the Erwinia that can easily be killed by it will die off quickly but those that have a bit of a resistance will not die and therefore if this bacteria (Erwinia) survive they will pass on their genetic information and create even more copper spray resistant bacteria (Erwinia).
Evolution (4-points of Natural Selection)
Variation
The variation in the Erwinia Bacteria is how resistant they are to the copper spray.
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Struggle
the struggle was that more and more copper spray was being used in the crops and else where in order to kill the bacteria that cause fire blight. (Basically their survival depends on weather they can survive through the copper spray and pass on their genetic information to the next generation as described in the section above.
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Environmental Selection
The environment selected the more resistant Erwinia because they are more likely to survive and pass on their genetic information and not be killed by the copper spray. The more resistant Erwinia were the more fit ones.
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Reproduction And Inheritance
As the more resistant Erwinia lived and passed on their genetic information this created more and more Erwinia that were resistant to the copper spray just like their parents. The gene that made the Erwinia resistant to the copper spray was therefore was inherited from generation to generation.
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For more information on adaptation/evolution and 4 points of natural selection refer to the Adaptation/Resistance section of this report.
Physiological Adaptation
The adaptation/resistance to the copper spray seen in the Erwinia is an example of a physiological adaptation because it is within the organisms internal systems.