Breeding Cover Crops – Setting the Stage for Discussion.

In this presentation I will set the stage by reviewing history of use, botanical characteristics, families and species and conclude with a discussion of the logistics of deploying cover crops successfully A cover crop is a crop that is primarily planted not for is own direct economic benefits (yield) but for its value in providing ecosystem services such as managing sensu latu. Such services might consist of managing various aspects of soil, crop, and environmental health. Cover crop species are as varied as the services they provide. While a plethora of species has been used for cover crop purposes, three botanical families comprise the vast majority, viz. grasses (Graminaceae), legumes (Fabaceae), and crucifers (Brassicaceae). Cover crops are grown during the “off season” for the major agronomic crop or during the transition from one cropping season to the next where multiple cropping seasons per year are the norm in agronomic production. In tropical and sub-tropical zones, maximum biomass accumulation is critically important, whereas in temperate zones other characteristic may have higher importance. Ease of cover crop establishment and termination need to be considered as well. The latter, in particular, is an important consideration in organic production systems under reduced tillage as might be desirable in tropical and sub-tropical high-rainfall production systems. Unlike major agronomic crops, the area of cover crop use and cover crop seed production are disjoint, complicating breeding efforts. Lastly, it needs to be remembered that everyone along the value chain of cover crop seed production and utilization has to have a profit interest in the outcome.