How does the policy of divide and rule affect an organization positively or negatively>

A divide and rule policy indicate that the work team is not coherent nor united behind a leader, under a business vision.

Although it would be better to know type of organization, and the kind of work it has before knowing the effects, generally speaking a team leader should unite the team members in attaining the objectives of the organization. 

One of the traits of a good manager is that he can make the work place atmosphere comfortable for the employees.  Respect and humane interaction (with good management) are factors that can help the employees fulfill their obligations in the firm.