Despite the 2008 season having a similar dry finish to that of 2007, grain yields in SA Pulse Breeding Australia (PBA) and National Variety Trial (NVT) trials were higher in 2008. The more favourable winter conditions in 2008 allowed lentil crops to produce sufficient biomass levels to allow significant grain production and acceptable harvest height.
The exceptions were late sown crops or crops in severely drought affected areas. Aldinga and the green lentil type Boomer averaged slightly higher yields (3 percent) than Nugget across all trials while Northfield and Nipper were slightly lower yielding (3 percent).
All eleven NVT and PBA lentil trials in SA were harvested last year. However results from Lameroo were disregarded due to low and variable yields. Average trial site grain yields ranged from 0.48 t/ha at Rudal on the Eastern Eyre Peninsula to 2.69 t/ha at Riverton.
Yields at higher rainfall sites were generally similar to their long term site averages while yields at medium and lower rainfall sites were generally lower.
The major factors influencing variety performance in 2008 trials were moisture stress post flowering and high temperatures during flowering and pod fill. Foliar disease, as in 2006 and 2007, had no impact on variety rankings in 2008.
Boomer generally had high relative yields at all sites in 2008 although its performance was not as convincing as it was in 2007.
It was substantially lower yielding than Nugget at Laura (19 percent) and only similar in yield at Willamulka, Maitland, Melton, Riverton and Turretfield.
At all other sites lentil growth was generally restricted to a greater extent by moisture stress and Boomer had superior yields to Nugget.
At these sites Boomers early flowering, greater early vigour and improved harvest height were favourable characteristics for aiding performance in the dry spring conditions.
Boomer is currently the highest yielding commercial lentil variety in long term southern Australian evaluation trials (2-3 percent higher than Nugget) primarily due to excellent relative performances in the dry years of 2006 and 2007.
However Boomer is best adapted to medium rainfall areas with mild finishing conditions to enable its large seeds to fully form.
Early sowing in favourable lentil growing environments may increase the risk of seed blemish from ascochyta blight and excessive biomass production leading to premature lodging.
Boomer is moderately susceptible to shattering at maturity (more susceptible than current varieties). Delayed harvest under some conditions can result in shattering and downgrading of seed quality.
Aldinga has generally been 5-10 percent lower yielding than Nugget, in long term evaluation trials in SA. Its improved performance in 2008 was largely due to high relative yields at moisture stressed sites.
At these sites its smaller plant type and earlier maturity timing than Nugget were better suited to the dry finishing conditions.
Nipper has dual resistance to ascochyta blight and botrytis grey mould and like in 2006 and 2007 these traits were no advantage to it last year.
However Nippers relative yield compared with Nugget was improved last year (3 percent less across all sites compared with 8 percent less in 2007).
This improved performance was most likely due to the more favourable winter growing conditions suiting Nippers need to produce sufficient biomass levels for high grain production.
Nipper had similar grain yields to Northfield across all trials in SA in 2008 but long term is around 5 percent higher yielding than this variety.
It provides a low risk option in medium and high rainfall areas where disease is a regular problem.
It is not as well suited as Nugget to low rainfall areas or short seasons however it generally performs similarly to Northfield under these conditions.
Current long term yields in southern Australia show Nipper having similar grain yields in all rainfall regions. This is most likely due to lower than average rainfall, reduced growing season length and an absence of disease in the high rainfall zones in recent years.
It is expected that Nipper will show a yield advantage in the high rainfall zones when seasonal conditions are more favourable for disease development.
The standout out feature of the 2008 evaluation trials was the performance of the advanced PBA breeding line CIPAL411.
CIPAL411 is one of a number of advanced breeding lentil lines from PBA Lentils currently undergoing seed multiplication with PB Seeds, Horsham.
CIPAL411 is an earlier maturing line with improved adaptation to short season environments.
It was very high yielding in NVT and PBA trials in 2008 averaging 19 percent higher than Nugget across all sites. It is expected to be available in 2010.
