Rice farming and the sustainability challenge

Rice cultivation and the promise of drip irrigation

Rice (Oryza sativa L.) is one of the most important staple foods in the human diet: more than half of the world’s population depends on this crop as part of their daily nutrition. While rice farming has ensured food security for millennia, it also ranks among the most resource-intensive agricultural practices, both in terms of water use and greenhouse gas emissions.

The traditional method of continuous flooding, which maintains 10–15 cm of water above the soil surface, consumes around 40% of the global irrigation water supply and accounts for 8–12% of anthropogenic methane emissions.

This impact is further exacerbated by climate change. Recent drought waves across Southern Europe and South Asia have shown how fragile the flooded-rice model has become. In Spain, during 2022–2023, water scarcity reduced cultivated areas by 40% and national production by 50%. In Sri Lanka, in the same period, approximately 50,000 acres of paddy fields were lost to drought and extreme temperatures. In a context of rising food demand, producing rice in the traditional way is increasingly unsustainable.

Drip irrigation in rice: a turning point for the sector

Growing rice “dry”? Yes, it’s possible

Over the past two decades, researchers, agronomists, and companies have been testing alternative irrigation systems to reduce water use and emissions without compromising yields. Among these, drip irrigation has shown the most promising results. Delivering water directly to the root zone—rather than flooding the entire field—allows rice to grow under aerobic conditions. This paradigm shift drastically cuts methane emissions (a study suggests by as much as 78%^[1]) and reduces irrigation volumes.

Drip irrigation, applied on the soil surface or through subsurface drip irrigation (SDI), offers another agronomic advantage: the integration of fertigation. Supplying nutrients in smaller, targeted doses increases efficiency and reduces losses from leaching or volatilization. This opens the door to precision rice farming—using less water and energy while enhancing the quality of the final product.

L’irrigazione a goccia del riso nel mondo

Field trials in major rice-producing countries highlight the benefits of drip irrigation, building a global map of experiences.

In China, recent studies^[2] demonstrated that subsurface drip combined with ammonium-based fertigation improved root growth, boosted yields, and enhanced water and nutrient use efficiency. In the arid Xinjiang region, drip systems with plastic mulch reduced irrigation needs by 15% without affecting yields, underscoring the importance of coupling drip irrigation with optimized nitrogen management^[3].

In Egypt, on clay soils, experimental trials achieved yields of up to 12.5 tons per hectare using driplines with 4 L/h emitters spaced 30 cm apart^[4]. Water productivity reached 1.66 kg of grain per cubic meter of water—double that of flooded systems. Similarly, research in the Mediterranean basin of Turkey confirmed water savings between 49–60%, with only a slight reduction in yields under the most restrictive treatments, but nearly doubled water productivity.

Positive results have also emerged in Iran^[5] and Iraq^[6], where comparisons between surface and subsurface drip showed higher yields than flooding and significant gains in water productivity. In Iran, surface drip outperformed subsurface drip in yield, while in Iraq, SDI produced better results with emitter spacing at 18 cm.

In Pakistan, multi-year experiments^[7] confirmed water savings above 70%, though with a risk of yield losses up to 47% if systems are not properly designed and managed. Finally, in India, “aerobic” rice irrigated with drip systems supported by IoT sensors showed yield increases and greater water use efficiency, highlighting how digital tools are key to making the transition successful.

Overall, the evidence is clear: drip irrigation in rice ensures substantial water savings and reduces emissions. Yet success depends on accurate system design, tailored to soil types and varieties, and on the integration of monitoring and automation technologies.

Irritec field trials in Italian rice paddies

In Italy, rice cultivation is concentrated mainly in the North, but innovative trials are also emerging in other regions, such as Sardinia, where drip irrigation has been successfully tested.

Research led by Giuseppe Giardina, AR&D Manager at Irritec, showed that drip irrigation can dramatically reduce water consumption compared to flooding, while maintaining competitive yields and excellent grain quality.

Even more striking were the food safety results: under aerobic conditions, heavy metal concentrations in rice kernels were significantly reduced. Analyses found arsenic almost absent in drip-irrigated rice, while cadmium levels were cut by two-thirds compared to flooded fields. This adds important value in terms of crop health and food security.

Farmers involved in these trials saw first-hand how drip irrigation ensures stable yields while enhancing rice as a viable cash crop in areas affected by water scarcity. Sardinia thus becomes a real-world laboratory for extending drip rice farming to other Mediterranean regions, producing a higher-quality grain while saving precious resources.

Designing a drip irrigation system for rice

Turning these results into practice requires agronomic expertise and proper system design. A drip irrigation layout for rice must consider soil type, variety, and climate. On sandy soils, surface drip may be preferable, while on heavier clay soils, SDI helps maintain uniform moisture in the root zone with fewer losses.

Emitter spacing, flow rates, and dripline layout strongly influence yields and efficiency, which is why professional design is essential. Irrigation management also changes radically compared to flooding: instead of maintaining a continuous water layer, farmers irrigate in small, frequent doses—typically every 2–3 days – with significantly lower volumes.

Modern drip systems also enable fertigation, which brings further benefits. Supplying nitrogen in fractional doses not only improves nutrient use efficiency but also reduces nitrous oxide emissions, another potent greenhouse gas.

Automation and sensors complete the picture, enabling real-time adaptation of water supply to crop needs and weather conditions.

Irritec solutions for sustainable rice farming

Irritec has long been committed to developing solutions that make rice cultivation more sustainable, efficient, and profitable.

Its portfolio includes all the components required for a complete drip system: from lightweight driplines such as IrritecTape® and eXXtreme Tape®, engineered to withstand tough field conditions while ensuring uniform delivery, to filtration units and polyethylene pipes that ensure long-term system durability.

To this, Irritec adds sensors, weather stations, and automation connected to DSS platforms, enabling precise irrigation and fertigation scheduling based on real-time field data.

Thanks to this integrated approach, Irritec provides not just products but a complete system—transforming rice into a high-efficiency crop ready to meet today’s environmental and market challenges.

NOTE:

[1] https://pmc.ncbi.nlm.nih.gov/articles/PMC8276196/

[2] https://www.mdpi.com/2223-7747/14/6/891

[3] https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1075625/full

[4] https://www.researchgate.net/publication/373429683_CROP_WATER_PRODUCTIVITY_OPTIMIZATION_FOR_RICE_CULTIVATION_UNDER_DRIP_IRRIGATION_SYSTEM

[5] https://wra.areeo.ac.ir/article_129353.html?lang=en

[6] https://sabraojournal.org/wp-content/uploads/2023/04/SABRAO-J-Breed-Genet-55-2-587-597-MS22-160.pdf

[7] https://www.sciencedirect.com/science/article/pii/S037837742400088X