Impact assessment

Controlling phalaris minor in the Indian rice-wheat belt

Date released
23 July 2002
Publication Code
IAS018
Authors

D Vincent & D Quirke

Overview

The ACIAR-managed project CS1/1996/013, Herbicide-resistant weeds of wheat in India and Australia: integrated management, was designed to find a long-term method of control of Phalaris minor, a problem weed of the rice-wheat cropping system of north-western India. By 1993, the weed had developed resistance to isoproturon, a herbicide which had delivered effective weed control for 15 years. The short-term solution, implemented before the ACIAR project commenced, involved identification and registration of a new set of herbicides. But these new herbicides were expensive. To ensure high adoption they needed to be combined with changes in wheat-growing techniques that would provide cost savings to help farmers pay for them. And to avoid the re-emergence of chemical resistance, they needed to be used sparingly as one element in a broader approach to weed management. The project team used these circumstances to field-test and encourage adoption of zero tillage, a technology that agronomists had been advocating for many years, but which had failed to capture the interest of Indian farmers.