The agent of controlled pollination in crops is man. Controlled pollination is the process of transferring pollen from one plant to another with a specific goal in mind, such as developing a new variety or increasing yield. In this process, humans intervene to manipulate the transfer of pollen, rather than relying on natural pollination by wind or insects. This is done by using tools such as brushes or by physically transferring the pollen by hand. Hence, the answer is "man".