Toward Production Systems Incorporating Ratooning/Perennial Grain Crops

Farmers, both smallholders in developing countries and industrial-scale producers in developed countries, need more options for sustainable intensification of crop production while also increasing support of multiple ecological functions (e.g., topsoil retention) to mitigate or preferably reverse long-term losses of ecological capital associated with row crop agriculture. These needs must be met under more challenging circumstances than those of the first ‘Green Revolution’, including rising input costs, diminishing water resources, increased climate variability, and degraded soil conditions. The development of perennial grain crops, such as wheat, sorghum, and grain legumes, is a potentially transformative innovation that could be a keystone in solutions to these multiple challenges. Smallholders in particular may benefit from this cropping system, to support their hard-won agricultural skills to feed their families. Deeper roots and longer growing periods mean more harvests, better protected soil and more resilience to fluctuations in rainfall – and amortizing seed and soil preparation/sowing costs over multiple cropping cycles may significantly change production economics, perhaps broadening utilization of hybrids. Genomics tools can speed the process from lab to field. The most drought resistant among the five most important cereal crops and a key dual-use (grain and biomass) crop in regions containing some of the world’s most degraded soils, sorghum (S. bicolor L.) may be an appropriate ‘early adopter of multiple-harvest cropping – however preliminary breeding is in progress on perennial variants of several major crops in anticipation of determining their roles and value in region specific cropping systems.