3072001 ; Lemerle et al. 2004 ), nutrient use efficiency (Anderson and Hoyle 1999 ) and
suitability for dual-purpose use (grazing and grain recovery (e.g., Anderson 1985 ;
Virgona et al. 2006 ) are also considered traits likely to contribute to future yield
increases.
4.2 Adoption of the Components of Conservation Agriculture
Australian dryland farmers have adopted zero tillage over more than 80 % of the
cropped area (ABS 2009b; Llewellyn and D’Emden 2010 ; Ward and Siddique 2014 ).
Some of the main reasons that farmers adopted zero tillage were - reduced fuel costs
from fewer cultivations, quicker seeding programmes, reduced wind erosion, better
water retention and better weed management from herbicides (Scott et al. 2013 ). One
of the biggest benefits of this new technology has been that farmers have been able
to sow crops much earlier. From 1978 to 1990, the mean midpoint of wheat sowing
progressed a day earlier per year on a national scale (Stephens and Lyons 1998 ).
When the recent midpoint of wheat sowing was calculated, this trend to earlier sow-
ing has continued with farmers now planting in late April and early May (Fig. 4 ).
Fig. 4 The mean midpoint of wheat sowing for Australia from 1978–1990 (Stephens and Lyons
sowing date survey 1998 ), 2007–2014 (Source: Birchip Cropping Group, BCG- sites were spread
across Australia)
Dryland Agriculture in Australia: Experiences and Innovations