1991 Annual Report for ANE91-001
Improving Crop Adaptation to Alternative Systems (LNE91-025,LNE91-025.2)
Summary
The objectives of this project were to identify corn varieties that are well adapted to specific low-input or sustainable agriculture practices, and to provide this information immediately to farmers and extension personnel.
Other project goals involved identifying traits critical to improved corn adaptation to sustainable conditions; initiating a corn breeding program to develop new genetic materials adapted to existing and proposed low input sustainable agricultural procedures; and working with farmers, extension agents and seed companies to improve availability of varieties adapted to sustainable systems and ability to choose appropriate varieties.
This work was carried out in four cropping systems: (1) no-till, which received zero tillage and recommended herbicide and nitrogen inputs; (2) low nitrogen, which received full tillage and herbicide inputs, but only a minimal starter nitrogen application; (3) red clover interseeding, which received full tillage, no herbicide, a minimal starter nitrogen application, and medium red clover sown between rows at layby and plowed down prior to planting the following spring; and (4) a conventional check system, which received full tillage and recommended herbicide and nitrogen inputs.
Two major field activities were carried out: an evaluation of current commercially available corn varieties in the four cropping systems studied, and a divergent selection breeding program to develop unique genetic materials with improved performance in specific cropping systems.
After two years of research, progress was made in understanding the interaction between corn varieties and different cropping systems. It is apparent that performance of a variety in a conventional production system is not generally an accurate indicator of how that variety will perform in alternative low-input, sustainable production systems. In other words, the best variety in one system is not necessarily best in other systems.
Some specific traits important to productivity of corn varieties under low-input, sustainable systems were identified. These traits include good stand establishment, appropriate leaf angle, dark green color under stress (as shown by readings indicating chlorophyll content of the leaves), and synchronization of pollen shed with silk emergence under stress. Root system traits are very important to productivity under LISA systems. These traits have received very little study and have not generally been part of plant breeders' selection criteria. Therefore, they represent untapped potential for genetic improvement. We initiated development of unique genetic materials with specific adaptation to the LISA systems studied. Numerous presentations, field days, and publications documented the progress of this work. However, because funding for this project was terminated after only two years, corn varieties appropriate to sustainable agriculture were not identified.