Location: Corn Insects and Crop Genetics Research2012 Annual Report
1a. Objectives (from AD-416):
The objectives of this research are to 1) breed high yielding corn with enhanced nutritional value for the Northern Corn Belt, 2) adapt the corn to the conditions found on farms using sustainable farming practices, and 3) achieve acceptance of these cultivars by end users such as livestock farmers and poultry producers.
1b. Approach (from AD-416):
1)Interact with a team including USDA and ISU scientists and PFI to select varieties for breeding, plan experiments, test corn, develop methods for screening lines for desired traits, and for outreach and publication efforts. 2)Utilize a crossing, inbreeding and test-cross facilitated breeding program to identify and fix corn lines with desired traits, and crossing and recurrent selection to improve desired traits such as the content of methionine and lysine in grain. 3)In conjunction with others, fully utilize and improve the accuracy of a near infra red spectroscopy-based test for screening whole grain samples for essential amino acids. 4)Evaluate the adaptation of lines and their hybrids to organic farming systems in the Northern Corn Belt, including their agronomic traits and their ability to suppress weeds. 5)Help coordinate on-farm trials with hybrids and publicize the results. 6)Interact with end-users such as seed and organic poultry companies with advice and to help facilitate poultry company sponsored feeding trials with grain from our cultivars.
3. Progress Report:
The project involves breeding corn for superior nutritional value including increased content of essential amino acids. These varieties are adapted to low input, sustainable farming conditions where nitrogen is primarily made available to corn through the decomposition of soil organic matter and organic manures, and where the corn will need to out compete inherent weed populations because herbicides are not used. All selections by the cooperators are made under organic cropping conditions. Our 2011 crop breeding research focused on the development and testing of corn varieties with stability of grain yield production and grain quality adapted to organic crop production conditions. Our focus areas follow: 1) Concurrent development of open pollinated and hybrid varieties. Open pollinated (OP) varieties permit growers to save part of their harvest to use as seed for planting in future seasons, a benefit where seed is expensive or availability limited, where performance is important, but absolute uniformity is not needed, where seed cost overshadows profit margin. The industry standard for corn is hybrid varieties due to the perception of superior quality, uniformity and performance as promoted by the proprietary seed corn industry. Both OP and hybrid seed corn varieties have a place in organic crop production programs; 2) Evaluation of yield via replicated variety trials included a bacterial inoculation trial, application of biodynamic preparations, and a replicated trial of our diverse breeding lines: hybrid and OP, and the United States Testing Network (USTN) trial of commercially developed hybrids as a final testing phase before their release; 3) A yield trial for evaluation of nitrogen use efficiency and efficacy of bacterial inoculation was planted as a means to evaluate atmospheric nitrogen fixation. Nitrogen fixation was not evaluated in 2011. Plot to plot carryover of bacterial inoculum in the planter boxes created cross contamination between treatments. The data would not have been definitive; 4) Protein and methionine levels were evaluated for key populations using near infrared. Increased protein level improves feeding quality for humans and livestock. Methionine is a limiting essential amino acid in poultry rations which is currently available only in synthetic form. Increased methionine levels in feed corn would reduce the amount of supplemental synthetic methionine used to meet dietary needs of chickens; 5) Gametophytic incompatibility is a genetically inherited system preventing pollination by pollen sources not containing incompatibility gene. This gene occurs in nature and effectively isolates popcorn from pollination by field corn. Introduction of the gametophytic gene would “protect” or limit wind-blown field pollination during crop production limiting contamination from external pollen sources, i.e. Genetically Modified Organism (GMO) pollen. While important work, introgression of this gene into our populations and recovering the integrity of our breeding lines without undue carry-over of the popcorn genes is a challenge; 6) Agronomic characteristics were evaluated for some characteristics for a portion of the plots. Results and conclusions from the 2011 nurseries lead to selection and planting for trials in 2012: 1) Soil sampling and analysis was conducted on all areas planted to plant breeding research. Organic Materials Review Institute (OMRI) approved organic fertilizers were applied to meet soil test recommendations; 2) Comparison of nitrogen use efficiency and atmospheric nitrogen fixation will be conducted in a replicated yield trial utilizing low and normal nitrogen fertility levels, with and without bacterial inoculation. The nitrogen source utilized was independent of other nutrient sources permitting reservation of a low nitrogen fertility area for direct comparison of performance in plots applied with recommended levels of nitrogen. We will refine our sample harvest and preparation techniques to better evaluate the plant’s nitrogen sourcing; 3) Breeding lines representing germplasm from diverse backgrounds: plant introductions, gametophytic incompatibility and conventional germplasm, were planted in a replicated yield trial; 4) GMO free entries from the USTN nursery were planted for yield and agronomic characteristic evaluation; 5) Breeding nursery includes areas for small quantities of seed production for future trials, population development through sib mating, self-pollination to produce inbred lines and new hybrids. New hybrids will include back-crossing P.I. introgression lines and top crosses, test crosses to determine combining ability; 6) NIR protein evaluation was complete pre-planting for some of the populations. The lowest protein lines were dropped from the nursery. Larger populations were subjected to selection based on visual appearance of the seed; 7) Plant characteristics will be evaluated for all entries in the nursery to provide a matrix for comparison within and between families. Data will include plant stand, seedling vigor, plant height, silk date, tassel date, stalk and root lodging. Our emphasis on coupling yield, grain quality and agronomic traits needed for organic crop production is unprecedented. We are making progress in developing new, unique corn varieties, not duplicated in the private sector but needed by the organic sector. As we continue our work, our understanding and the depth of our program increases. Our future direction is to release cultivars fitting an organic ideotype which includes grain quality, agronomic reliability and excellent grain yield.