Selecting seed for sowing requires care and attention
Grain growers are encouraged to pay particular care and attention to the retained seed they are planning to sow in season 2012.
While the extent of seed affected by weather during the 2011 harvest is considerably less than the previous year, close scrutiny of seed set aside for planting is being advised.
The Grains Research and Development Corporation (GRDC) says that any grain subjected to wetting at harvest is more susceptible to poor germination, low vigour and degradation during storage and handling.
To assist growers in determining whether grain is viable for sowing and what is an appropriate and effective seed management program, the GRDC offers a detailed Retaining Seed fact sheet.
The fact sheet states that the symptoms of seed quality deterioration can range from mild, such as a loose and wrinkled seed coat in some pulses, to more advanced, such as seed staining, fungal mould and visible signs of germination.
It is essential that growers recognise whether the damage is cosmetic or the symptom of a seedborne disease and if it will impact on germination.
GRDC Southern Regional Panel chair David Shannon says that in accordance with the fact sheet, unless canola seed was harvested before any weather damage it should not be retained for sowing due to the vulnerability of canola’s small seed.
“And irrespective of availability, hybrid canola seed should not be retained for seed as the crop will not be true to the original first generation (F1) seed,” Mr Shannon said.
“Any retained seed should be graded and tested for germination and vigour. Testing for seed-borne disease is also recommended, especially with saved pulse seed.”
Other key points contained in the GRDC fact sheet that growers should consider when retaining grain for seed include:
• While a laboratory seed test should be used to establish the germination percentage of on-farm retained seed before sowing, especially if it has been weather damaged, a simple on-farm germination test can be done in soil. This will give a good indication of emergence and seedling vigour as at germination.
• Seed-borne disease generally cannot be identified from visual inspection so requires laboratory testing.
• Achieving and maintaining low temperature, humidity and grain moisture content for stored grain is even more critical if grain has been weather damaged. As weather damaged seed deteriorates faster than sound seed it should not be stored for more than 12 months.
• With many weedy pulse and cereal crops in a wet season, desiccation or crop topping often becomes necessary. Depending on timing and chemicals used, this could affect seed quality for sowing.
• Grain must not be retained for seed when glyphosate has been used in pre-harvest applications.
• Seedling emergence can be affected by sowing too deeply, cold or wet soil, some seed dressings and herbicides, and hard-setting soil.
The fact sheet is accessible via www.grdc.com.au/GRDC_FS_Retainingseed and is also available free (plus postage and handling) through GRDC’s Ground Cover Direct – freecall 1800 110044 or email firstname.lastname@example.org.
GRDC Project Code: COR00019
Media releases and other media products can be found at www.grdc.com.au/media
Contact: Sharon Watt
GRDC Project Code