Root Distribution, Nutrient Uptake, and Yield of Two Upland Rice Cultivars under Two Water Regimes

• Grant number: 12/24390-0
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: February 01, 2013
• End date: July 31, 2013
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Carlos Alexandre Costa Crusciol
• Grantee: Carlos Alexandre Costa Crusciol
• Host Institution: Faculdade de Ciências Agronômicas (FCA). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Upland rice (Oryza sativa L.) cultivation has been increasing in global importance due to the decreasing water availability for floodirrigatedrice. The use of sprinkler irrigation to supplement rainfall and the identification of cultivars more adapted to lower wateravailability could be effective alternatives for producing upland rice without yield losses while using less water. The objective of thisfield study was to evaluate the root distribution, plant nutrition, and grain yield of two drought tolerant upland rice cultivars undertwo water regimes in the Cerrado Region of Brazil during two growing seasons. The main plots were two water regimes (rainfedand sprinkler-irrigation plus rainfall). Subplots were two upland rice cultivars Carajás and IAC 201. Low water availability reducedroot growth by 7% and grain yields were from 2644 to 4002 kg ha-1 on average for rainfed and sprinkler irrigation treatments,respectively. Carajás had a significantly better root distribution, nutrient uptake, and higher grain yield (3732 kg ha-1) comparedwith IAC 201 (2914 kg ha-1) averaged over two growing seasons and water regimes. There were no treatment interactions. Ourresults suggest that, even when cultivars with a higher tolerance to less water availability are used, using sprinkler irrigation toaugment limited rainfall during dry periods may be a viable method to increase upland rice grain yields. (AU)