Irrigation management of Romaine lettuce in Histosols at two spatial scales: water, energy, leaching and yield impacts

Abstract

Lettuce is an important crop in Canada, mainly grown in South West Quebec muck soils. Lettuce is sensitive to water stress during periods of high crop water requirements, which result in important yields decrease mainly due to tip burn. This physiological disorder can be controlled by adequate irrigation, which is affected by spatial distribution patterns of water needs at different field scales. Such patterns result from spatial variability of soil properties and water drainage, and from evapotranspirative processes affecting local crop water needs at a given time. This study aimed at evaluating irrigation management performances (water and energy consumption, leaching and yield) for Romaine lettuce in a Histosol at two spatial scales, local and global (0.5 and 7 ha). Three field experiments were performed during summers 2010 and 2011 at two sites of 7 ha presenting a high spatial variability in available water (AW). The set up was divided into three zones equipped with wireless tensiometers. The critical irrigation threshold for initiating irrigation was −30 kPa for a low (< 4mm) potential evapotranspirative (ET) demand and −15 kPa for a higher ET (> 4 mm) [1]. Results indicated that local irrigation management has resulted in marketable yield increase of 16.5 to 18.2% depending on years, but resulted in 21.2 to 23.6% more water (and consequently energy) use with respect to global management. Higher frequency and quantity of applied irrigation water has resulted in higher tracer leaching in the second year in the local irrigation management approach.

Root Water Uptake by Romaine Lettuce in a Muck Soil: Linking Tip Burn to Hydric Deficit

“…5). The results are also consistent with those of Périard et al (2012), who found a significant reduction in tip burn using an irrigation threshold of −15 kPa for the average of three tensiometers at depths of 15, 30, and 45 cm when the ET was >4 mm d −1 . These results also suggest that monitoring at more than one depth provides a better diagnosis of potential stresses because the data showed that water uptake occurs at many depths.…”

“…Histosols on the site were classified as Haplohemists (Soil Survey Staff, 1999). The experimental site was chosen for its high variability of soil water availability and the thickness of its organic soil profile (Lafond et al, 2015; Périard et al, 2012). The thickness of the organic soil profile is closely related to soil water availability calculated throughout the entire rooting depth (Hallema et al, 2015a).…”

“…In 2009, lettuce production in the United States represented approximately 112,870 ha and 4.1 million Mg of lettuce, with 2.4 million Mg of head lettuce, 1.2 million Mg of romaine lettuce, and 0.5 million Mg of leaf lettuce (Lu et al, 2011; Mossler and Dunn, 2014). Lettuce is, however, known to be highly sensitive to yield losses caused by tip burn (Périard et al, 2012). Tip burn is a physiological disorder recognizable by the brown‐black necrosis that appears on the margins of young leaves (Kirkby and Pilbeam, 1984; Saure, 1998).…”

Long‐Term Effects of Peatland Cultivation on Soil Physical and Hydraulic Properties: Case Study in Canada

“…Water management studies on organic soils have shown that the oxidation is accelerated by excessive drainage, which in turn also increases the rate of biodegradation, reduces the water storage capacity and hydraulic conductivity (Schlotzhauer and Price, 1999), and in some cases causes the organic soil to subside more than a centimeter per year (Shih et al, 1998). Vegetables such as lettuce are very sensitive to water stress during the growth stage when water demand is high and can quickly develop physiological disorders (tip burn) resulting in yield loss (Périard et al, 2012). Understanding the effects of peatland cultivation on soil physical and hydraulic properties is essential for optimizing water management on organic soils, yet there is no quantitative knowledge of the large‐scale effects.…”

Optimal Irrigation for Onion and Celery Production and Spinach Seed Germination in Histosols

“…Specifically, the objectives were to determine the yield and quality response of these crops to soil water potential irrigation thresholds and to establish links between soil hydraulic properties and the identified thresholds. Numerical models could be successfully used to derive such thresholds (Périard et al, 2013), but simple steady‐state analytical solutions (Yuan and Lu, 2005) requiring few parameters could be easily implemented to achieve such goal. The comparative performances of such analytical solutions have never been evaluated.…”