Working towards building a sustainable cotton industry for the future

Cotton management

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CSIRO’s cotton management research is supported by the Cotton Catchment Communities Cooperative Research Centre (CCCCRC) and the Cotton Research and Development Corporation (CRDC).

Nutrition and fertilisers

Lint yields from flood-irrigated cotton have increased steadily over the past 25 years. High-yielding cotton has a high demand for nutrients, but often production is limited by soil fertility and the crop’s ability to accumulate nutrients.

CSIRO’s NutriLOGIC program helps cotton growers decide on fertiliser applications. Data gathered on the nutritional status of their plants and soil is used by NutriLOGIC to recommend or plan a suitable fertiliser program.

Nitrogen, phosphorus and potassium fertilisers are often used at high rates in irrigated agricultural crops like cotton so we are identifying ways to improve the efficiency of fertiliser use and reduce emissions of greenhouse gases.

Soil management and crop rotation

We have long term experiments to assess the value of rotation crops in cotton cropping systems to improve soil health. This work is identifying which are the quickest and best management practices to build up soil organic matter and sequester carbon.

Soil can be improved by:

  • reducing tillage and creating permanent beds
  • rotating crops
  • applying appropriate amounts of fertilisers.

Better soil health results in:

  • increased organic matter and carbon levels
  • improved soil nutrient levels
  • reduced compaction
  • reduced soil sodicity
  • improved soil condition (tilth).

A recent finding showed that the legume vetch promotes soil health and can increase cotton yields by up to 18 per cent when used as a rotation crop. Similar results have been found with faba bean crops, which also reduce the need to apply high rates of nitrogen fertilisers for following cotton crops.

Vetch can also reduce the incidence of black root rot, an important disease of cotton, but may increase Fusarium wilt.

Weed management

Herbicides, cultivation and manual chipping are all used to manage weeds in cotton. Traditionally residual herbicides were used to control weeds because they were the most effective option but with the advent of Roundup Ready™ cotton, it is possible to reduce reliance on them.

We are incorporating several herbicide resistance genes into our leading cotton varieties. RoundupReady Flex™ varieties contain genes conferring tolerance of the glyphosate herbicide, allowing Roundup herbicide to be sprayed directly onto the cotton crop without harming it, but killing the weeds within it. Roundup is preferred by farmers as it has less environmental side-effects than older residual herbicides.

Roundup Ready™ and Roundup Ready Flex™ are owned by the Monsanto Company, but delivered in Australia in CSIRO cotton varieties.

Planting configuration

In Australia, irrigated cotton is usually grown in rows one metre apart with between 8 to 12 plants per metre of row.

By narrowing the row spacing to less than 1 metre, more plants can be grown per square metre of land. The plant population density of the crop affects crop growth and yield due to competition between adjacent plants.

CSIRO is researching different plant populations and row spacings to determine under what conditions narrow row spacings out-yield conventional row spacings, to pin point when cotton growers should adopt the practice and how to maximise yield and maintain quality.

Read more at: Narrow rows widen chance of higher yields information sheet.

Helping farmers manage cotton

CSIRO has developed CottonLOGIC, a suite of decision tools, to help cotton growers achieve best management practice. CottonLOGIC helps growers and their advisers manage cotton crops efficiently for optimum yields and quality.

For updated and expanded information each season and easy access to the latest cotton research, see CottonLOGIC [external link].


References

Roundup Ready™ and Roundup Ready Flex™ are trade marks owned by the Monsanto Company.