What causes oak trees to develop galls and how do they benefit the gall wasp?

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SUMMARY

Oak trees develop galls primarily due to the chemical secretions of gall wasps, which manipulate the tree's leaf growth mechanisms. This process resembles a controlled tumor formation, where the wasp's excreted chemicals interfere with the tree's genetic and hormonal functions, specifically affecting auxins and cytokinins. The galls serve as nutrient-rich incubators for the wasp larvae, showcasing a complex interaction between the insect and the plant. Understanding this phenomenon involves exploring the biochemical pathways and the role of similar agents like Agrobacterium tumefaciens.

PREREQUISITES
  • Understanding of plant hormones, specifically auxins and cytokinins
  • Knowledge of gall wasp biology and lifecycle
  • Familiarity with plant pathology and anomalous growth patterns
  • Basic concepts of genetic manipulation in plants
NEXT STEPS
  • Research the biochemical mechanisms of gall formation in oak trees
  • Study the role of Agrobacterium tumefaciens in plant growth manipulation
  • Investigate the phenomenon of witches' broom and its causes
  • Explore the genetic interactions between gall wasps and oak trees
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Entomologists, botanists, plant pathologists, and anyone interested in the intricate relationships between insects and plants, particularly in the context of growth manipulation and disease.

Jimster41
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How does the Gall Wasp get an Oak tree to make these?
http://ento.psu.edu/extension/factsheets/galls-oak
https://en.wikipedia.org/wiki/Gall_wasp

I am not able to find anything other than "induced by chemicals secreted by the wasp" more or less. I have been looking at these over the last six months. They seem to be manipulations of the tree's leaf growth mechanism to make an incubator - Is it interfering at the genetic level? The galls receive/steal nutrient from the tree in a way that seems similar to a cancer. Is it in effect an intentionally induced and controlled tumor that an insect has evolved specifically tuned to control the growth mechanism of a form of life from an entirely different kingdom? Do we understand this chemistry? I collected these in the woods near home - cut a couple open to see the larval wasp. The large brown ones are mature the wasp exited through a little pin hole. I mean wtf? The structure in them is amazing. Totally different geometric path compared to a leaf.

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Google Agrobacterium tumifaciens - it is a bacterium that induces local cells to produce auxins and cytokinins - out of place. Normally the plant hormones control new tissue differentiation. Tissue differentiation gets completely screwed up by the wrong timing and amounts of the hormones. So what should you expect would be the chemicals excreted by the wasp? Chemicals that imitate or are identical to the plant hormones.

They interfere with cell division/cell differentiation.

Look up witches broom - it is both timely (Halloweeen) and very interesting. Most galls and other wierdnesses on hardwood tree species are the result of anomalous growth. In this case a virus is the bad guy.

http://onlinelibrary.wiley.com/doi/10.1111/j.0014-3820.2001.tb00765.x/abstract
 
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