|DE AVILA, LUIS - Universidade Federal De Santa Maria|
|DE MARTIN1, LUIS - Universidade Federal De Santa Maria|
|MEZZOMO, RAFAEL - Universidade Federal De Santa Maria|
|RSFATTI, JOAO - Universidade Federal De Santa Maria|
|CAMPOS, ROGERIO - Universidade Federal De Santa Maria|
|CERIMBRA, DIOGO - Universidade Federal De Santa Maria|
|MACHADO, SERGIO LUIS - Universidade Federal De Santa Maria|
|CARLESSO, REIMAR - Universidade Federal De Santa Maria|
|MARCHESAN, ENIO - Universidade Federal De Santa Maria|
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/18/2016
Publication Date: 3/1/2015
Publication URL: http://handle.nal.usda.gov/10113/62796
Citation: De Avila, L.A., De Martin1, L.F., Mezzomo, R.F., Rsfatti, J.P., Campos, R., Cerimbra, D.M., Machado, S.O., Massey, J., Carlesso, R., Marchesan, E. 2015. Rice Water use efficiency and yield under continuous and intermittent irrigation . Agronomy Journal. 107(2):442-448. https://doi.org/10.2134/agronj14.0080.
Interpretive Summary: This paper reports season-long and monthly irrigation applications made between 2002 and 2013 by producers to cotton, corn, rice, soybean and catfish in the Mississippi Delta. These groundwater irrigation results are based on a combined total of 1,311 field and 48 pond measurements. The methods, amounts, and frequencies of irrigation were determined by farmers. Rice was the most heavily irrigated, receiving an average of 920 mm irrigation. At 526 mm, catfish received the second highest level of irrigation. Corn received 312 mm irrigation per growing season but this amount was not different from the 281 mm applied to soybean. Cotton received the least irrigation at 177 mm. A strong correlation was observed between the amounts of rainfall received and the average amounts of irrigation applied to row crops, showing that producers were responsive to precipitation when making irrigation applications. Zero-grade rice fields were the most efficient rice irrigation systems studied, receiving 574 mm irrigation. The second most efficient rice irrigation system was straight-levee fields using multiple inlets at 795 mm. Similar amounts of irrigation were applied to contour and straight-levee rice fields. In terms of row crops, producers generally applied the most irrigation using furrow versus flood and/or pivot methods. The amounts of irrigation applied to cotton did not change over this study. In contrast, applications to rice, corn, and soybean increased by about 17 mm per year, respectively.
Technical Abstract: In the Brazilian state of Rio Grande do Sul, rice (Oryza sativa L.) is predominantly grown using continuous fl ood irrigation, which requires large quantities of fresh water. Due to increasing scarcity and demand for water, modern agricultural systems need to produce more food with less water. Th e objective of this study was to evaluate the eff ect of diff erent irrigation management systems on water use effi ciency, quantity of water loss due to runoff , and rice grain yield. Th e experiments were conducted from 2007 through 2010 at an experimental station of the Plant Protection Department of the Universidade Federal de Santa Maria, Rio Grande do Sul state, Brazil, on an Albaqualf sandy-loam soil. Treatments consisted of two irrigation management systems: continuous fl ooding (CF) at approximately a 10-cm fl ood depth and intermittent irrigation (II) where the fl ood was allowed to fully subside before being re-established to a 10-cm depth. Intermittent irrigation increased storage of rainwater by reducing runoff water by 56% compared with CF. In addition, II reduced irrigation water use by 22 to 76% resulting in a 15 to 346% increase in water use effi ciency (WUE). Rice yield was not aff ected by II compared with CF. Intermittent irrigation provides greater water conservation, does not reduce rice yield compared with CF, and improves the WUE of rice.