Energy efficient routing protocols in WSN for precision and smart agriculture

The rising global need for food has increased the demand for smart agricultural technologies that boost productivity while staying sustainable. Wireless Sensor Networks (WSNs) are central to Precision Agriculture (PA) by facilitating real-time tracking of environmental factors like soil moisture, temperature, and humidity. However, WSNs encounter notable challenges mainly concerning energy use, network lifespan, and efficiency in data transmission. This survey delivers a thorough PRISMA-based systematic review of energy-efficient routing protocols tailored for WSN in PA. Initially, 250 research studies were identified from major databases, and after removing duplicates and screening titles, 150 articles remained. After thorough checking 50 papers are removed as they are irrelevant to the research questions. 43 high quality research articles satisfied quality assessment criteria and published in between 2016-2025 are considered for full text review and detail analysis. The selected routing frameworks are classified into six categories: clustering based, optimization based, fuzzy based, machine learning based, security aware and hybrid approach. This study focuses on energy efficient routing protocol of WSN for precision and smart agriculture. It investigates performance of various Quality of Service (QoS) metrics like energy consumption, packet delivery ratio (PDR) and network lifetime. This study analysis impact of different types of protocol. The analysis demonstrates that clustering and optimization based frameworks provide maximum improvement in network lifetime and data delivery. Whereas, machine learning and hybrid approaches show better scalability, adaptability and intelligent routing under dynamic agriculture scenarios. While, security aware frameworks improve reliability under malicious attacks but increase computational overhead. Overall the study insights into the strengths and limitations of existing routing frameworks and concludes future enhancement of energy efficient routing protocol for precision and smart agriculture.