Trials show barley does better when sown early

But like wheat, most slower maturing or early sowing option barley varieties, tend to commonly suffer important yield losses when sown later than their recommended window. Yield loss from all varieties was generally major when sown well outside their sowing window.

These were key outcomes from trials conducted at the IA Watson Grains Research Centre at Narrabri in 2014 by NSW Department of Primary Industries (DPI) researcher Rick Graham. 

Trials were undertaken as part of the Grains Research and Development Corporation and DPI co-funded Variety Specific Agronomy Project.

Soil type was black self-mulching clay, faba beans had been grown the previous year and treatments were sown with Supreme Z extra at 60 kilograms a hectare.

Navigator and Oxford, long-season types, yielded their best from the earliest sowing, April 23 sown trials (about six tonnes/ha) but suffered losses of about 1t/ha or more when sown on May 15, with big losses from June 12 and July 4 sowings.

GrangeR, a new malt accredited mid to slower maturing variety yielded well in the April 23 and May 15 but also with big yield decline from the two later sowings.

Compass, a mid/early maturing type undergoing malt accreditation, yielded well in the April 23 and May 15 sowings, and also credibly from the June 12 sowing. Similarly early maturing Fathom, a feed grain quality variety, and recently malt accredited varieties La Trobe  and Scope CL, also did not suffer significant yield penalties from the earliest sowing and yielded well in the May 15 sowing.

Results illustrate the benefit of sowing in the early part of the sowing window, particularly for the longer season varieties, which showed significant decreases in yield and quality (increased screenings/decreased retentions) with delayed sowings.

Delayed sowing impacted on grain quality parameters (for example retention, a measure of grain plumpness) with a range of variety and sowing time responses. Newer cultivars such as Compass and Fathom maintained good grain stability across most of the sowing windows.  

Compass had improved grain retentions compared with Commander. It is similar agronomically and requires similar management to minimise lodging risk.

GrangeR, a Gairdner maturity, also had improved grain retentions and stability compared with Gairdner, further highlighting breeding improvements in yield and quality. 

Longer maturing varieties adversely affected by delayed sowing most likely because of high starting soil nitrogen and a typical warm dry seasonal finish.