2005, Volume 13, Paper 16

ISSN: 1883-5675

Valuing a Test for Nitrogen Status in Rice

Rajinder P. Singh – Research Economist with NSW Department of Primary Industries at the Yanco Agricultural Institute, Yanco

Robert Williams – Research Agronomist with NSW Agriculture at the Yanco Agricultural Institute

John Mullen – Principal Research Scientist with NSW Department of Primary Industries at Orange

Khaled Faour – Economist with NSW Department of Primary Industries at the Yanco Agricultural Institute, Yanco

Laurie Lewin – director, Rice CRC at the Yanco Agricultural Institute, Yanco

Abstract

Nitrogen is a crucial input for the efficient production of rice and is generally applied in two split treatments, before flooding the rice paddocks at sowing time and within a week after the beginning of the panicle initiation stage. There is no pre-sowing test to estimate nitrogen requirements and farmers use cropping history to make this decision.
The aim of this study was to first value the information to growers provided by a nitrogen test for soils of rice paddocks and then estimate the returns to the industry from investments in R&D to develop this test. In our approach the information provided by the test allowed growers to revise their expectations about soil nitrogen status according to Bayesian decision theory and consequently to use nitrogen more profitably. We found that the test is likely to provide information potentially valuable to growers at around$2/ha and that research in developing the test has been a profitable investment for the Rice CRC with a benefit cost ratio just above one. As the accuracy of the test is improved to current industry standards, its use will become more profitable.

Key words: rice, nitrogen, risk

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