Source: CSIRO Plant Industry newsletter

Preliminary results from CSIRO research in Narrabri have shown that genetically modified insect-resistant cotton may also be more water efficient.

Two years of field experiments by CSIRO Plant Industry's Mr Dirk Richards and Mr Stephen Yeates, show that under normal full irrigation, Bollgard® II cotton used ten per cent less water than an equivalent conventional variety and had higher yields.

Bollgard® II makes up most of the Australian cotton crop and has reduced pesticide use by up to 80 per cent.

Research is now optimising agronomic management of Bollgard® II as it tends to produce bolls earlier than conventional cotton because insect damage does not delay early crop growth.

Bollgard® II and conventional cotton extract soil water at a similar rate, but Bollgard® II has a more compact growing season so uses less water overall for the same or higher yields.

Bollgard® II had lower yields only when it was moisture stressed from peak flowering to the end of flowering when boll filling started.

Soil moisture stress applied to conventional cotton at the same time did not affect yield as much, due to later flowering and a better ability to compensate later in the season.

This research is helping growers fine tune their water management strategies for Bollgard® II.

This research is supported by the Cotton Research and Development Corporation and the Cotton Catchment Communities Cooperative Research Centre.

More information: http://www.pi.csiro.au/enewsletter/PDF/PI_info_Bollgard.pdf