Too wet to forget - reducing the impact of excessive rainfall on productivity : Final report 2014/046

Abstract

Too wet to forget – reducing the impact of excessive rainfall on productivity, was established due to the large productivity losses associated with La-Nina events in the sugarcane industry. The effect of waterlogging on the crop has also been largely ignored for decades. The project had four main activities:

1. A field trial in Tully to investigate whether speed of establishment of varieties was an important trait in excessively wet environments;

2. A field trial in Ingham to investigate waterlogging tolerance of current varieties;

3. Development of a method to impose waterlogging on sugarcane grown in pots;

4. Screening of sugarcane varieties for waterlogging tolerance in pots.

Below average rainfall limited the field experiment in Tully, but varieties with differing growth traits performed in a similar manner irrespective of harvest time in the first ratoon crop. This suggested there is a relatively wide range of phenotypes associated with optimum crop performance in these environments. Differences in waterlogging tolerance of current varieties were found in the field experiment. Knowing which varieties have better waterlogging tolerance allows growers to select the best variety for blocks prone to waterlogging. It highlights the importance of having accurate information on waterlogging tolerance in QCANESelectTM. The project developed a method to impose waterlogging on sugarcane growing in pots. The method was able to maintain anaerobic conditions within the root zone and resulted in typical waterlogging responses such as the development of adventitious roots at the soil surface. Pot experiments were then conducted to test current varieties for waterlogging tolerance. While differences were found between varieties, the reliability of this information is unclear and needs further development. It is suggested that future work include metabolomics approaches to determine differences among varieties.