Short communication. Effect of deficit irrigation on curly lettuce grown under semiarid conditions

Abstract

Field experiments were conducted to characterize the effects of deficit irrigation on curly lettuce (Lactuca sativa var. Crispa cv. Bohemia) evapotranspiration, water use efficiency, marketable yield, yield components and mineral contents. The experiments were performed under semiarid climatic conditions in Erzurum province (east of Turkey) in the summer periods of 2005 and 2006. Irrigation water levels were selected to be 100% of usable soil water in full irrigation treatment (control) (T-100) and 80%, 60%, 40% and 20% of usable soil water in deficit irrigation treatments (T-80, T-60, T-40 and T-20, respectively). Average seasonal evapotranspiration was 232 mm in T-100 and 121 mm in T-20. Average marketable yield was 39.49 Mg ha -1 in T-100 and 14.57 Mg ha -1 in T-20. A linear relationship (y=0.23x-13.97; R 2 = 0.94) was found between seasonal evapotranspiration (x) and marketable plant yield (y). According to the regression equation, the yield response factor (k y ) was found to be 1.39, and the coefficient of determination 0.91. Average water use efficiency was 168.88 kg ha -1 mm -1 in T-100 and 117.39 kg ha -1 mm -1 in T-20. The lowest plant length, width, steam diameter, leaf number, macro and micro element content values were obtained for T-20 in both years.Additional key words: curly lettuce, deficit irrigation, evapotranspiration, macro and micro elements, yield components. ResumenComunicación corta. Efecto del riego deficitario en la lechuga rizada bajo condiciones de clima semiárido Se estudiaron los efectos del riego deficitario sobre la evapotranspiración, eficiencia del uso del agua, producción comercial y los contenidos minerales de la planta de lechuga rizada (Lactuca sativa var. Crispa cv. Bohemia). Los experimentos se realizaron bajo condiciones climáticas semiáridas en la provincia de Erzurum (este de Turquía), durante 2005 y 2006. Los niveles de agua aplicados fueron el 100% del agua útil del suelo en el tratamiento control (T-100), y el 80%, 60%, 40% y 20% de agua útil del suelo en los tratamientos de riego deficitario (T-80, T-60, T-40 y T-20, respectivamente). La evapotranspiración estacional media fue de 232 mm en el tratamiento T-100 y 121 mm en el tratamiento T-20. La producción comercial media fue de 39,49 Mg ha -1 en el tratamiento T-100 y 14,57 Mg ha -1 en el T-20. Se encontró una relación lineal (y = 0,23x-13,97; R 2 = 0,94) entre la evapotranspiración estacional (x) y la producción comercial de la planta (y). Según la ecuación de regresión, el factor de la respuesta de la producción (k y ) resultó ser 1,39 y el coeficiente de la determinación 0,91. La eficiencia media del uso del agua fue 168,88 kg ha -1 mm -1 en el tratamiento T-100 y 117,39 kg ha -1 mm -1 en el tratamiento T-20. Los valores más bajos de longitud, anchura, diámetro del tronco, número de hoja, macro y microelementos se obtuvieron en el tratamiento T-20 en ambos años.Palabras clave adicionales: componentes del rendimiento, evapotranspiración, lechuga rizada, macro y microelementos, riego deficitario.Abbreviat...

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

“…5 and 7). The results are, therefore, consistent with previously reported work on Ca translocation, transpiration, and tip burn (Choi and Lee, 1999; Gallardo et al, 1996; Kuslu et al, 2008; Molina‐Montenegro et al, 2011; Napier and Combrink, 2005; Palencia et al, 2010; Saure, 2005).…”

“…The results of this study are, therefore, consistent with the literature (Karam et al, 2002; Coelho et al, 2005; Kuslu et al, 2008; Capra et al, 2008; Mansuroğlu et al, 2011; Bozkurt et al, 2009; Bozkurt and Mansuroğlu, 2011) concerning the importance of eliminating root water uptake deficit by managing irrigation to meet 100% of the ET demand. The results are also consistent with the general understanding that Ca‐related physiological disorders are associated with short periods of limited Ca 2+ supply to the plant, which is itself associated with limited water fluxes.…”

“…Irrigation has been shown to produce good results, as demonstrated by Cox and Dearman (1981), who reduced tip burn incidence from 72 to 16% using drip irrigation and night fogging. Irrigation would then contribute to better Ca translocation throughout the plant, as shown by Kuslu et al (2008), who found that Ca concentrations in plant tissues decreased by 5.2 to 10.5% when irrigation was insufficient (80% of evapotranspiration [ET] demand) compared with irrigation management based on 100% of ET demand. However, studies based on unique critical thresholds failed to reduce tip burn.…”

Ameliorative Effects of Plant Growth Promoting Bacteria on Water-yield Relationships, Growth, and Nutrient Uptake of Lettuce Plants under Different Irrigation Levels

“…Some researchers determined similar ET values with our results. Kuslu et al (2008) found average 232.3 mm ET value for fully irrigated curly lettuce in Erzurum, Turkey. Kadayifci et al (2004) obtained that ET of fully irrigated lettuce was 285 mm under greenhouse conditions.…”

Oxidative discolouration in whole-head and cut lettuce: biochemical and environmental influences on a complex phenotype and potential breeding strategies to improve shelf-life

“…from rainfall events, which cannot be controlled) can also have a significant impact on lettuce shelf life, increasing both caffeic acid levels and PAL and PPO activity, resulting in increased browning in processed lettuce (Luna et al 2012). Irrigation can also have a large effect on the mechanical properties of the lettuce leaf by influencing cell expansion and tissue turgor pressure (Kuslu et al 2008). Higher relative water content in whole head tissue at harvest increases susceptibility to damage during processing and subsequent pinking development.…”