Western Australia grain growers are encouraged to have a seed storage strategy in place for the 2015 harvest to preserve seed quality and protect phosphine – the only effective fumigant available to them for controlling grain storage insects.

In addition to selecting the best quality seed for storage from paddocks with the lowest weed numbers, growers should look to store grain with low moisture content and in low temperature aerated storage facilities.

Research funded by the Grains Research and Development Corporation (GRDC) has shown that storing seed at lower moisture levels ensures higher germination rates following storage periods, particularly where hot summers are experienced, such as in WA.

According to Ben White (pictured), from the GRDC’s grain storage extension team, seed untreated with seed treatment should be stored in an aerated, pressure-tested sealable silo (that meets a three-minute half-life pressure test), allowing the silo to be effectively fumigated and seed disinfested if there is an insect outbreak.
 

Storing untreated seed is recommended because growers can safely sell surplus seed that does not contain chemical residues, and they still have the option of applying a fungicide or disease seed treatment to seed after it is outloaded at seeding time, leaving any remaining seed uncontaminated by the treatment.

Growers who store seed in unsealed storages have few options against incidences of insect attack and are limited to using seed treatments with an insecticide active ingredient such as cypermethrin or thiamethoxam, because phosphine is not effective and cannot be used in unsealed silos.

If growers apply a seed treatment to seed in unsealed silos soon after harvest, they are encouraged to spend a little extra to include an insecticide active to protect the seed from insect attack over the summer storage period. Uniform coverage is essential to ensure efficacy.

But growers are reminded that the use of most seed treatments severely limits how grain can be used, and prevents it from being sold for export or into the domestic market for animal feed.

To avoid the risk of contaminating bulk storage silos, only apply seed treatments to grain stored in segregated seed silos.

WA growers are encouraged to contact Mr White who, where possible, can come to their farm to pressure test silos or host a free seed or grain storage workshop. He can be contacted on 1800 WEEVIL (1800 933 845).

Practical information about all aspects of grain storage is available on the GRDC Stored Grain Information Hub storedgrain.com.au.

Details about results from GRDC grain storage research projects are available in the GRDC Grain Storage Supplement. It is available at www.grdc.com.au/GCS119, and is included in the November-December edition of the GRDC magazine Ground Cover. To subscribe to Ground Cover visit www.grdc.com.au/groundcover.

The GRDC National Grain Storage Extension Project has been extended for a further three years to continue building growers’ knowledge of grain-storage management practices and to deliver tools to respond to issues.

By investing in grain storage research, the GRDC aims to support growers to introduce and maintain excellent stored grain management for human consumption, stockfeed and seed.