Agnes,
It could be just normal dessication that a pine goes through, salinization from chemicals in your water bringing out too many salts, and yes, a fungus of some kind that can be treated if you catch it quickly. Pine trees, like miniature Norways, that are grown in pots are very prone to all these. I would take either a picture or, better yet, a cut portion of the tree to your local nursery and have them look at it.
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The bond that links your true family is not one of blood, but of respect and joy in each other's life. Rarely do members of one family grow up under the same roof.-- Richard Bach [i]Illusions