I am sorry: when trying to follow this thread I was not allowed and the following RG-notice popped up:  

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 So -only partially answering your question: have you ever tried to read some "Handbook" or special literature on Plant Anatomy or do you attend courses at your University: I really do hope your PI's / Assistant Professors etc. have some clue about your task of university studies....

Please read Plant anatomy by katherine Esau. Many books on techniques of plant anatomy exist. Search in the market of Springer- Verlag or Oxford Univerisity.

Dear Patricia,

Thank you ... I am still searching, I will try some techniques in Laboratory.