Prototype of automated irrigation system improves the yield of potatoes ( Solanum tuberosum L . ) in Riobamba-Ecuador using wireless network sensors-WSN and 6

DOI: 10.24133/maskay.v9i2.1058 25 MASKAY Abstract—The aim of this study was to optimize irrigation water in the potato (Solanum tuberosum L. cv INIAP Natividad) crop to ensure the maximum productivity of the crop, using WSN according to the agro-ecological conditions of the area, which have allowed to monitor environmental parameters in potato cultivation and have ensured an efficient control system in irrigation. The WSN irrigation network was implemented using four Arduino modules configured with 6LoWPAN; two modules controlled the solenoid valves together with FC-28 sensors, which capture soil moisture, and through the DHT11 sensor the temperature and relative humidity. The fourth module functioned as a gateway through which information is sent to a database developed in PostgreSQL. Additionally, a Web server (Apache) was configured to visualize the control of the drip irrigation system developed in php, JAVA. It was concluded that the T1 (automated irrigation), which had achieved an evidence with a higher productivity in the potato cultivation in 19.2%, with a water consumption of 20% less than the T2 (manual irrigation). This evidences a clear saving of the hydric resource and an optimum development in the potato crop when comparing it with traditional irrigation system.


I. INTRODUCTION
HE applications of the Wireless Sensor Networks (WSN) has grown worldwide, play an important role to increase the ubiquity of the networks with low cost and easy implementation smart devices, using standards such as IEEE 801.15.4 in the physical layer and 6LoWPAN in the network layer [1].
The same ones that are not compatible with the TCP/IP protocol stack.For this reason, the IETF (Internet Engineering Task Force) developed a 6LoWPAN (IPv6 over Low-Power Wireless Personal Area Networks) communication standard which improves its functionality [2].
Prototype of automated irrigation system improves the yield of potatoes (Solanum tuberosum L.) in Riobamba-Ecuador using wireless network sensors-WSN and 6LoWPAN Prototipo de Sistema automatizado de riego mejora el rendimiento de la papa (Solanum tuberosum L.) en Riobamba-Ecuador usando sensores de redes inalámbricos-WSN y 6LoWPAN Oswaldo Martínez, Carla Argüello G., Juan León, Paúl Cherres, Gisela Cujilema T MASKAY A WSN is a network formed by a series of small low-cost, low-energy, and easily-deployable sensors.Providing scalability, flexibility, and cost reduction, it is a viable solution for precision agriculture applications.WSN technologies are used in agriculture to provide remote monitoring of parameters such as temperature, relative humidity, luminosity, among others, in order to create a simple and effective interaction environment to monitor the growing of crops [3].
One of the most outstanding applications of these networks is AP, agriculture of precision, which emerged from the 80`s and is a method that proposes the use of modern technologies and communication tools that are capable of facilitating the continuous collection of physical variables involved in the development of production for subsequent analysis and immediate decision making [4].
Ecuador is a country with a deep agricultural vocation, which prioritizes the production of crops such as potatoes, considered the basis of human nutrition, especially in the Ecuadorian sierra [5].
Potato is a demanding crop of water and very sensitive to water deficit, which is why an important good water supply during all stages of its phenological growth stage, otherwise it may cause disorders in the tuber.
The potato plant is sensitive to water stress and water availability in the soil cannot be less than 30% to achieve optimum yields.In the potato crop, a high availability of assimilates promotes the growth of roots, stolons, leaves, and branches [6].
The effect of water stress is the reduction of foliage growth for the partition of assimilates to the tubers, which determines a decrease of the crop cycle.The highest water demand occurs in the plant growth and germination stages of the tubers, which is where the optimum crop development is assured, the other plant development stages will require the water resource but in a smaller proportion [6].
The water resource is both limited and vital agricultural input in agriculture, its optimal distribution is a priority.Currently, different irrigation methods are installed lacking a system that together allows to measure soil moisture, control irrigation time, and to identify the portion of soil that really needs to be irrigated.This is a disadvantage due to the irrigation deficit causes a low yield in its production and, on the other hand, the excess of irrigation can trigger permanent soil infertility [7].
The aim of this study was to optimize the irrigation water in the potato (Solanum tuberosum L. cv.INIAP Natividad) crop to ensure maximum crop productivity by exposing an exploration of the relevance and real benefits of the automation of drip irrigation using WSN and 6LoWPAN wireless network sensors in Riobamba-Ecuador.

A. Study area
The study was conducted at the Irrigation Experimental Center, Macaji campus of the Escuela Superior Politécnica de Chimborazo-ESPOCH, Riobamba, Ecuador located at an altitude of 2821 meters above sea level, a Latitude of 1° 39'18.82''S,Longitude 78°40'39.99"with an average temperature of 13.5°C, an annual rainfall of 350 mm and a relative humidity of 66.4%.For the investigation in the field, 6 parcels of 10×10 meters each other were installed in a total area of 600 m 2 of net area for the assay with a separation of 2 meters among them, in each plot were located ten rows of 0.8 m of length and 0.2 m of width, were located in each plot.The drip irrigation system was implemented using a line of 0.25 m drippers and a flow rate of 1.02 liters per hour.

B. Network design
A WSN is a network of short range, low speed, and low energy consumption that consists of a set of spatially distributed autonomous nodes that monitor their environment [7].
The designed network consists of six nodes, three of them are sensor nodes, two are actuating nodes and the main one, is the network gateway.All of them were installed with a star topology in which each sensor/actuator node (final device) maintains only a direct communication path with the gateway.This simple topology is justified by the small number of devices that make it up.
In addition, a WSN network with 6LoWPAN was installed, which have allowed the monitoring of some parameters (soil moisture, maximum, and minimum temperatures, relative humidity) for the soil moisture content determination in real time and therefore, programming the irrigation efficiently according to the needs of the potato crop.Additionally, a portable meteorological station was installed to collect sufficient and important agroclimatic information.
The WSN are widely used in the monitoring and control of rainfall in agricultural areas of Colombia [8].The WSN were constituted by sensors capable of taking information from the environment with which they interact and then be processed and sent through wireless links to the network gateway to send them later to the base station, where information is stored and controlled for the decision making.
Currently, the most used networks are those that are based on the specifications of the standard IEEE 802.15.4.Given these concerns, 6LoWPAN arises due to the facility it offers to interconnect IPv6-based systems with TCP/IP architectures [9].
Finally, through the Contiki operating system, an IP communication system is incorporated for both IPv4 and IPv6, which makes easier and safer the information storage [10].

II. EXPERIMENTAL PROCEDURE
In this research, a complete block design was carried out with two treatments and three replicates, with automated irrigation (T1) and manual irrigation (T2).The procedure of planting the potato plants was as follows: location of the seed at 5 cm of soil depth and a distance among rows of 0.80 m and 0.25 m among plants.The second method is the sprinkler irrigation, which delivers water through a pressurized pipe network to the nozzles of sprinkler, which spray the water into the air [11].However, this method is less efficient than the drip one, since more water is losing due to evaporation and runoff.
Therefore, in this study we choose the drip strategy for our design.We note also that our proposed model is designed for a site-specific irrigation where the crops are characterized by a spatial temporal variation of the irrigation requirements.The variability comes from the soil type, crop type, crop, and meteorological conditions.The modular configuration of the automated irrigation system allows it to be scaled up for larger greenhouses or open fields.The automated irrigation system implemented was found to be feasible and cost effective for optimizing water resources for potato crop production.Besides the monetary savings in water use, the importance of the preservation of this natural resource justify the use of this type of irrigation systems.
Mostly, water management depends on types of soil such as alluvial sandy soil with different layers of sand and silt.If clay content having less than 5% and water retention capacity is less than 50 mm 3 /mm 3 , then it has to irrigate every 7 days.If well-drained red soil of high physical potential, but with low pH and clay is equal to 15-20%, then it has to irrigate every 20 days.The quality of potato crop depends on the type of water supply; water supply can be from different resources such as gravitational water, free drainage, rainfall, and available water, estimating soil moisture and relationship with crop yield using surface temperature and vegetation index [12].
Wireless sensor network (WSN) have many applications such as industrial automation, automated and smart homes video surveillance, traffic monitoring, medical device monitoring, monitoring of weather conditions, air traffic control, robot control, personal body area network [12].
Another similar study is carried out by [13], who through WSN-Wireless Sensor Networks, presents a solution for the monitoring of environmental quality in the city of Quito-Ecuador, which, beyond monitoring the air quality, extends to the most conflictive sectors of the city of Quito-Ecuador.
In [14], applied an Internet Protocol version 6 (IPv6) in a wireless sensor network (WSN), for the remote monitoring of short-cycle crops at the La Pradera farm, this research presents a process similar to the one applied but does not show the contribution Significant use of wireless networks in potato crop productivity.
The present research on the contrary potentiates the use of WSN with 6LoWPAN for the monitoring and control in real time of the productive process of the cultivation of the potato and makes possible the taking of opportune decisions to assure an optimal development of the same.
Use of Information technology introduced a new concept in agriculture as Precision Agriculture.The precision framing adoption is a cyclic process of data gathering, diagnostic, data examination, accuracy field operation and evaluation.For state and condition monitoring of crop there is visual inspection, color estimation and mold localization.For monitoring the conditions wireless sensor network is preferred since it provides results in real time and there is no limitations of distance and physical barrier, as data provided is in real time [15].
The irrigation system efficiency reflects the interaction between irrigation and crop yield.The major problem of agriculture is the scarcity and quality of water resources.For the quality water it has no direct effect on water use efficiency, but irrigation system has great effect on water use efficiency [16] The results of this study showed that farmers, when implementing the system, will achieve a significant saving of the time it takes them to collect potato crop data, which allows them to have greater control of the variables involved in the process.The contributions that these automated control systems can give the user are multiple and increasingly necessary to reduce task time, optimize resources and respond immediately, solving problems with greater efficiency.

V. CONCLUSION
The interoperability of WSN networks with TCP/IP architectures has been demonstrated by presenting the data collected by the WSN in the designed web application.The irrigation system can be adjusted to potato crop response and in addition, a variety of specific crop needs, which requires minimum maintenance.With the implementation of the system, an intelligent irrigation has been obtained that provides the potato plant with the amount of water necessary and sufficient for its development, thus avoiding unnecessary waste of scarce water resources.The research responds to the need of the farmer, to have a technological tool that allows him to acquire information on agroclimatic parameters that were previously carried out manually.The implementation of the WSN with 6LoWPAN has allowed automating the irrigation of a potato crop, thus achieving a technology tool that allows quick access to data to help decision making.The studied cultivar Natividad INIAP of potato crop was attended to in its water requirements, and a good branching, yield, size and crop development, which was observed under the assay conditions.

Fig. 1 .
Fig. 1.Diagram of Fig. irriga DHT Gate C. T belt m o elec rece from T con the that D. A mod and been con sens •