The Internet of Things (IoT) is a thriving technology in almost all fields of human life to make their lives easy. Smart Agriculture is one of the IoT applications on which farmers are widely switching to improve productivity and reduce labor costs. As IoT involves the Internet, data transmission technology creates the possibility of privacy/security breaches concerning users’ data. The cybercrime rate may also increase in IoT-based agriculture (IoTA). Thus there must be ready concerning digital forensics in IoTA. Various review articles are available regarding the emerging cyber attack, cybercrime, and forensics challenges in IoT applications like smart home, smart city, smart healthcare, smart grid, smart retail, smart supply chain management, and smart agriculture, while a few review articles on IoTA security and forensic challenges. This review paper is focused on IoTA solutions and their security and forensics challenges. The systematic literature review method has been used for this study which includes articles published from 2011 - 2021. This article has brought the limelight on IoT architecture and its application in agricluture (IoTA) to emphasize on its introduction, architecture, challenges and issues related emerging cybercrimes and digital forensics. At the end, this review paper discusses various challenges in securing IoTA systems and presents future directions for research.