What would be your reaction If an employee is dedicated to work, but direct manager does not see this?

Agreed with previous answers that have been given by experts here

If it happens it means that manager has not so good managing skills, as he must define who works and who doesn't... And, yes, I agree with Mr. Vinod, I'll try to make manager notice that

There is an assessment of the employee based on the themes and business entrusted to him, and based on the results and performance measurement is to know the performance of the employee and therefore there will be a semi-annual evaluation to see deviations in the employee

Dedication is subjective and non measurable. Identify performance indicators which are realistic and measurable and have a mutual agreement and recorded. Undoing so is to get self trapped into unpleasant situation. 

Direct manager should observe his subordinates closely. If he fails to do so, he should be notified, because ignoring hardworking employees will get the whole business organisation down!

The question is a strange one, unless you feel you are dedicated to your job and you are feeling unrewarded by your manager. If this is the case I would suggest that you list out all your achievements for the past year, including how well you met deadlines and goals, request a meeting with your manager and site down with the evidence and have a informal chat about it and also how you feel.

In large teams sometimes you just get lost, these are the times that communication becomes a very important tool in your toolbox to unlocking your demotivation, and get back to feeling a valued team member.

 Try to make the direct manager see this.

notify the direction manager by writing a letter a of appreciation for the employee.

I Agree with the answer been added by EXPERTS ................. Thanks.