In developing countries like India, more than 70% of the population depends on agricultural fields for their livelihood. Under natural conditions, both agricultural and horticultural crops face significant yield losses due to pest and disease outbreaks, affecting crop productivity. Chemical pesticides are often used to protect crops from pests and diseases, and to increase crop yield. According to the WHO (World Health Organization) estimate, approximately one million people were seriously affected by manual pesticide spraying, posing a serious threat to the agricultural labourers involved in spraying work.
In the technological world, with rapid advancements in science, many developments are happening around the world to enhance crop productivity and reduce human effort. One such invention is the unscrewed aerial vehicle (UAV) aircraft developed for spraying pesticides on crops. A typical UAV is an aircraft that can fly without a human pilot and is controlled by a radio channel. In recent times, pesticide spraying UAVs have been developed, which consist of an automated drone system and a sprinkling system. The UAV sprinkling system auto-navigated using GPS coordinates to spray pesticides on the required areas or crops. The sprinkling system is attached to the lower region of the UAV, which has a nozzle beneath the pesticide tank to sprinkle the pesticide downward onto the crop canopy. Spraying drones with multi-spectral cameras are also available in the market; these are capable of monitoring the field and generating spatial maps. These maps show the exact conditions of the crop, allowing agricultural operations (e.g., pesticide/herbicide/nutrient spraying) to be carried out accordingly. These technologies are useful where human interventions are not possible for spraying chemicals on crops, one of the main reasons being the scarcity of labor.
Chamuah & Singh (2019) suggested that in the governance of emerging technologies like UAV, specific values, such as trust, transparency, safety, autonomy, and environmental friendliness, assumed high significance. They also noted that UAVs have the risk-taking ability in adverse weather conditions. The UAV technology also creates value (social, economic, and environmental) for deployment in the crop insurance business in India.
Unmanned aircraft systems (UAS), commonly referred to as drones, are an emerging technology that has changed the way many industries conduct business. Precision agriculture is one industry that has consistently been predicted to be a significant locus of innovation for UAS. However, this has not been the case globally. The agricultural aircraft sector in the United States is used as a case study to consider different metrics for evaluating UAS adoption, including a proposed metric: the normalized UAS adoption index. In aggregate, UAS operators only make up 5% of the number of agricultural aircraft operators. However, the annual number of new UAS operators exceeded that of manned aircraft operators in 2022. When used on a state-by-state basis, the normalized UAS adoption index reveals regional differences in UAS adoption, with western and eastern states exhibiting higher UAS adoption rates, while central states have significantly lower rates. This has implications for UAS operators, manufacturers, and regulators as this industry continues to develop at a rapid pace. (Rodriguez, 2023)
Drones in Indian Agriculture
The marginal and small farmers constitute 78.2 per cent of the farming community in India. Although tremendous technological advances have been made in various fields in India, agriculture is still lagging in the large-scale adoption of technologies. However, the use of drones in the agriculture industry is steadily growing for sustainable agriculture. the use of drones can be advantageous in the case of pesticide spraying, replacing labour-intensive and hazardous conventional methods, particularly in difficult areas such as hills, and to carry out synchronized spraying in places where pest and disease outbreaks damage the crops heavily. Timely actions can also be taken to prevent losses from biotic stresses.
Limitations in manual sprayingincludes Lesser efficient cum labour-intensive, Low precision with risk of pesticide poisoning to human beings, more pesticide and water wastage, increased cost on agro chemicals leading to soil and water pollution and synchronized spraying is not possible.
Advantages of Drone Spraying
Human health safety: Agriculture sprayer drones are remotely controlled from a distance by trained personnel. Therefore, the direct involvement of farmers or farm labourers with poisonous chemicals is avoided.
Agrochemical savings: Approximately 30% of agrochemicals/pesticides are saved due to the high degree of atomization achieved during spraying. Pesticides in the form of chemical fog can be sprayed at all stages of the crop.
Water conservation: The drone utilizes ultra-low volume spraying technology, saving up to 90% of water compared to traditional spraying methods.
Lower cost: The cost of spraying is reduced by 85-90% with drones, compared to conventional spraying methods.
High field efficiency and coverage:A drone can spray 50-100 acres per day, depending on the capacity of the drone, which is 30 times more than a traditional knapsack sprayer.
Synchronized spraying: Drone spraying facilitates mass spraying during severe pest and disease outbreaks.
Easy to handle and maintain: It has low maintenance cost, a long productive lifespan, and its parts replacement is simple.
Social distancing: Drone technology can save labor and also help maintain social distancing norms during the COVID-19 pandemic.
Dutta & Goswami (2020) concluded that Drones provide real-time and high-quality aerial imagery compared to satellite imagery over agricultural areas. Additionally, applications for localizing weeds and diseases, determining soil properties, detecting vegetation differences, and producing accurate elevation models are currently possible with the help of drones. Drones will enable farmers to gain a deeper understanding of their fields. Therefore, farmers will beassisted with producing morefood while using fewer chemicals. Nearly all farmers who have used drones have achieved some form of benefit. They can make more efficient use of their land, exterminate pests before they destroy entire crops, adjust the soil quality to improve growth in problem areas, improve irrigation to plants suffering from heat stress, and track fires before they get out of control. Therefore, drones may become an integral part of agriculture in the future, helping farmers manage their fields and resources more effectively and sustainably.
Rana& Mahima (2020) concluded by recommending that more farmers adopt drone techniques to improve their agricultural outcomes, and considering recent research trends to employ agricultural UAVs, control technologies, and equipment development is essential.
To popularize drone spraying and make it available locally, the field extension functionaries working in Krishi Vigyan Kendras (KVKs) need to be trained and oriented towards popularizing drone usage through field demonstrations of various agricultural applications. Secondly, drone sprayer is to be made available at KVK, Vriddhachalam, Cuddalore district. The KVK will effectively monitor field situations and recommend when drone spraying is necessary. The drone will be hired to farmers along with technical personnel, and the fee thus collected will be used for drone sprayer maintenance. Method demonstrations and training sessions on drone spraying will be provided to stakeholders.
