Physiological traits and cereal germplasm for sustainable agricultural systems

Plant breeding is not a discipline that readily comes to mind when agricultural sustainability is being considered. Sustainability is normally associated with farming practices such as stubble retention, direct-drilling, or amelioration practices such as contour farming or liming, or rotation practices for nutrient management and disease control. The contribution of plant breeding will be in providing germplasm for these changed practices and devising new methods of selection. This paper reviews opportunities where plant breeding can contribute to improvements in sustainable farming practices. The emphasis is on rainfed cropping systems and cereal improvement. The main contribution for breeding is to (i) increase crop water and nutrient use so that less escapes from the root profile; and (ii) preserve the soil resource with conservation farming systems by developing cultivars specifically adapted to changed farming systems and competitive cultivars that reduce herbicide use. To achieve these outcomes identification of desirable traits, suitable selection methods and development of appropriate germplasm are discussed.