Agriculture and forestry sector contributes 28.89% in national GDP (AICC, 2018). Agricultural land of Nepal is becoming less and less due to population growth and rapid urbanization, CBS (2011) shows that, the average land holding is limited to 0.68 ha per household.. Precision agriculture a comprehensive system designed to optimize agricultural production through the application of crop information system, advanced technologies on production, and improved crop management practices. It includes several activities like crop planning, tillage, planting, intercultural operation, harvesting, and post harvest processing of the crop. Technological interventions in precision horticulture include genetic conservation, genetic engineering, integrated nutrient management, protected cultivation, post harvest technology, micro irrigation and fertigation technologies (Nabi et.al., 2017). Thus, Precision and protected horticulture are the tools of modern agriculture and more precisely, protected horticulture comes under precision horticulture. Nepal has progressed significantly in developing horticultural technologies like tissue culture, TPS technology, IPM & IPNS, vermi-composting, drip and sprinkler irrigation system in the recent days (Pradhan et. al., 2016).
‘Precision farming’ or ‘Precision Agriculture’ aims at increasing productivity, decreasing production costs and minimizing the environmental impact of farming (Maheswari et al., 2008). The challenges to feed the world in 2050 are becoming more and clearer. This calls for producing more with less and intensifying production in a sustainable way. Protected horticulture offers opportunities for maximum resource efficiency, high quality production and contributes greatly to the nutrition security as part of the world food production. This is achieved by both simple and advanced techniques for farm, crop and climate management, precise application of resources (water, fertilizers, energy) so that environmental impact can be controlled and the use of resources optimized (WUR, 2018). is done.
Status of precision and protected horticulture in the world:
The total protected cultivation area in South East Europe amounts to about 101888 ha, accounting for approximately 5.15% of the total vegetable cultivated area.The vegetable production from the above area is about 7962240 Mt, i.e. approximately 19.09% of total vegetable production (Gruda and Popsimonova, 2017). There are many forms of protected cultivation in Asia, which provide a better way than the open field to increase the quantity, quality, and off-season production of vegetables, fruits and ornamentals. China alone has more acreage of horticultural crops production under protection than that of the other continents combined. In 2010, there was more than 4 million ha protected vegetable (including melon and watermelon) production in China, which was over 95% of all protected production in China, and over 80% of all protected vegetable production in the world. Protected cultivation facilities in Asia range from low-cost polytunnels made of recyclable materials, which rely mostly on natural solar energy input, to very expensive and sophisticated plant factories, which exclude natural solar energy and rely almost exclusively on artificial energy input. Many horticultural crops (including those unique in Asia) and different stages of plants (including transplants, container plants, plants to harvest fruits and vegetables, etc.) could be produced profitably under various forms of protected cultivation (Yunyan et al., 2013).
Objectives of precision horticulture
- Increasing profitability and sustainability is one of the major objectives of precision horticulture. It balances inputs (seed, variety, fertilizer and pesticides) with crop needs according to agro climatic condition. In long run it sustains profitability.
- Precision farming also aims at optimization of product quality by way of using sensors, which detect the quality attributes of the crop, and thus inputs are to be applied accordingly.
- It optimizes production efficiency of each site or within each region using different modern management system.
- Conventional farming methods apply herbicides, insecticides to the entire field, site-specific variable rate application puts these chemicals where the problem appears is necessary. Thus, effective and efficient pest management can be achieved by using precision farming.
- Precision horticulture begins from crop planning and thus includes such tillage practices which conserve the soil or disturb the soil to its minimum. Besides, water is efficiently applied by using techniques like drip irrigation etc. This prevents their leaching through ground water or as runoff through surface water.
- The risk of environmental damage is reduced if better crop management decisions are being made to meet demand and decrease in the net loss of any applied input to the environment.
- It generates large amounts of data that are spatial records of inputs and outputs for fields. These data can help to create more accurate management plans.
- It also helps to improves production decision and on farm research for profit maximization in sustainable way.
Constraints involved in precision agriculture
- High associated cost for production
- Small land holding of farmers and heterogeneity of cropping system.
- Subsistence farming system
- Lack of technical expertise and knowledge.
- Technological gaps among research, education and extension organization and at farmers level.
Elements of precision farming
Information, technology and management are combined into a production system that can increase productivity, improve product quality, allow more efficient use of chemicals, conserve energy and provide for soil and ground water protection.
Information like crop characteristics (different growth stages, water and nutrient requirement, crop health, insect pest incidence), soil characters (physical and chemical properties, colour, texture, nutrient status, salinity and toxicity, soil temperature), microclimatic data (daily, weekly, monthly, seasonal), agro metrological information (canopy temperature, wind direction, speed, humidity, solar radiation and light intensity, light composition), irrigation and drainage facilities, water availability and other planning inputs of interest according to farm are major information needed for precision farming.
It is an integrated agricultural management system incorporating several technologies like Global positioning system (GPS), Geographical Information System (GIS), Yield monitors (yield monitors are crop yield measuring devices installed on harvesting equipment), Variable Rate Technology (VRT), remote sensing and etc. are some of technology widely used in precision farming.
- Management (decision support system)
Just having information about variability within the field does not solve any problems unless there is some kind of management/Decision Support System (DSS) exist.
- Identify environmental and biological states and processes in the field that can be monitored and manipulated for the betterment of crop production.
- Choose sensors and supporting equipment to record data on these stages and processes.
- Collect, store and communicate the field recorded data.
- Process and manipulate the data into useful information and knowledge.
- Present the information and knowledge in a form that can be interpreted to make decisions.
- Choose an action associated with a decision to change the identified state or process in a way that makes it more favorable to profitable crop production.
A key component of this farm management approach is the use of information technology and a wide array of items such as GPS guidance, control systems, sensors, robotics, drones, autonomous vehicles, variable rate technology, GPS-based soil sampling, automated hardware and software.
Protected horticulture practice means cropping techniques of horticultural commodities wherein the micro climate surrounding the plant body is controlled partially or fully as per the requirement of the crops. With the advancement in agriculture various types of protected cultivation practices suitable for a specific type of agro climatic zone have emerged. Out of which green house, plastic house, lath house, cloth house, net house, shade house, hot beds and cold frames etc is use in Nepal (IDSC, 2009).
Advantages of protected horticulture
- Higher yield per unit time and area, recorded increase in yield up to 5 to 8 times.
- Undulating terrains, saline, water logged, sandy & hilly lands can also be brought under cultivation under protected farming.
- Suitable for water scarce area, it saves water up to 50% as compare to open field condition.
- Crop grows consistently, healthier, uniform quality fruits and matures fast.
- Early maturity results in higher and faster returns on investment.
- Fertilizer use efficiency also increases by 30%. Inter culturing and labor reduced.
- Better insect, pest and disease control and less use of pesticides
- Offseason production and efficient use of scarce resources.
- Grow plants anywhere at any season.
- Less use of agrochemicals, environmental friendly.
- Nursery raising and hardening of sapling/seedling under protected cultivation.
Disadvantages of protected horticulture
- Higher initial investment.
- Need higher degree of management, labor intensive.
- Not all crops are profitable under controlled condition.
- Need advanced technology, technical manpower and continuous support for production. By : Arun Kafle and Padma Nath Atreya