Protected agriculture: increasing yields and reducing chemical and water use

In Oman, as in the rest of the Arabian Peninsula, ICARDA scientists are working to improve greenhouse management techniques

To address the challenges of protected agriculture, a leading method of agricultural production in the Arabian Peninsula (AP), ICARDA developed and implemented the Integrated Production and Protection Management (IPPM) program to maximize its benefits and increase product yield and quality.

Greenhouses have intrinsic challenges, including soil disease, insect infestation, over-use of chemicals, and inefficient water use. Therefore, in collaboration with NARES in AP countries, ICARDA developed IPPMs to institute improved greenhouse management techniques to minimize the use of chemical pesticides, increase plant growth, and decrease the spread of fungal infection and other diseases.

In Yemen, IPPM methods included soil solarization, soil mulching, mechanical removal of infested plants, yellow sticky traps for insects, bio-insecticides, insect proof netting on openings and cooling pads, as well as insect-proof nets over greenhouses. The implementation of the latter methods reduced the number of chemical sprays needed for the plants (number of sprays decreased by 38%, from two sprays with 18-22 sprays without IPPMs). Downy mildew also decreased, as did nematode infestation (down to 26% from the control of 47%).

In Kuwait, soil solarization alone, under drip irrigation, provided effective weed and nematode control while increasing tomato yields by 50%.

Soilless Production

Because water scarcity in the AP makes it impossible to have enough water for high-yield high-value crops even in optimal conditions, ICARDA has also worked to research and implement soilless techniques. Vertical cultivation for high-value produce (including herbs, green vegetables, or fruit) involves using a tower of interlocking stackable Styrofoam pots with drainage holes. Hydroponics of tomato plants in the United Arab Emirates (UAE), for example, showed that 120 m3 of water were saved for each ton of tomato compared to conventional soil systems.

Additionally, upgrading a hydroponics system by adding an automatic controller for nutrient solutions, increased yield and water productivity by 11% to 50% in the UAE and Oman.

Cooling Systems Challenges

Studies in Qatar, Oman, and UAE showed that water for cooling exceeded water for crop production anywhere from two to six times (the range gap due to the growing season). For example, for tomato crops grown in Ras Al-Khaimah Station (UAE) during the 2014/15 season, the cooling system consumed over 200% of the water needed by the tomato crops themselves.

To address such discrepancies and increase water use efficiency, ICARDA introduced two approaches: net houses and the use of solar energy to enhance cooling system efficiency. Net houses generated similar yields to their cool greenhouse counterparts, even though the former were in production for 8 months of the year compared to the year-round "season" of conventionally cooled greenhouses.

To minimize insecticide use, maximize water efficiency, and produce high-quality yields, IPPM offers a way forward for creating productive protective agricultural environments that can better provide food and income security in the AP.