MICR 3220 Lecture 30: Lecture 30
15 Jan 2019
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Friday november 23 r d: bacteria: called the phytoplasmas (wall-less bacteria that are specialized just for the seive tubes) Last group of pathogens to be identified, this took a long time because the symptoms caused by phytoplasmas are the same as those caused by phloem limited viruses. Dna: around 600 diseases that are caused by these phytoplasmas. Coconut lethal yellowing phytoplasma: originally thought this disease was a virus. It is a disease of coconuts causing chlorosis, tree will eventually die form the infection. In miami and florida, 90% of the coconut palms were killed by this disease: the leaves die and drop off one after another leaving the tree looking like a telephone pole. For ornamental and production purposes, the caribbean palms were replaced with malayan coconut palms. If you look in the phloem using microscopy at phytoplasma, you see different shapes of cells because phytoplasmas have an irregular shape since they are wall-less.
