Progress 07/01/05 to 07/31/10
Outputs
OUTPUTS: Dr. Russell left the university suddenly in June, 2008. He did not leave us with any information as to progress on the project since the last update in October, 2007. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Dr. Russell left the university suddenly in June, 2008. He did not leave us with any information as to progress on the project since the last update in October, 2007.
Publications
- No publications reported this period
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Progress 10/01/06 to 09/30/07
Outputs
Objective 1: Undertaking genetic/breeding studies that will enhance breeding efficiencies. Approximately 400 F4 and F5 unselected families were developed from a cross between a small-kernel corn inbred and a large-kernel corn inbred. These two inbreds were selected from Krug open-pollinated varieties that had been selected divergently for 20 years for kernel size. The goal is to use these lines as a mapping population for kernel size. Objective 2: Developing alternative sources of corn germplasm, with particular focus on traits not emphasized by the private seed industry. Two red-kerneled and two blue-kerneled corn populations are being developed. The two red populations are from different backgrounds, so the expectation is that when crossed they will show some heterosis. The same is true for the two blue populations. Two approaches are being used to improve all four populations. One approach is mass selection, with greatest emphasis being placed on ear size and good
kernel set, absence of any kernel/ear rot, dark red or blue grain color, synchrony of male and female flowering,and acceptable late-season plant health. A selection intensity of approximately 5% was practiced in each population. A second approach is to cross one of each colored population to elite Stiff Stalk lines (yellow grain) and the other colored population to elite non-Stiff Stalk lines (yellow grain). These crosses were made this past summer. The purpose for making these crosses was to introduce higher grain yield and better plant health. In subsequent seasons, these crosses will be allowed to random-mate and then selection to recover the red and blue colors will be undertaken. In another selection program, a Stiff-Stalk and a Lancaster population are being developed that are homozygous for the recessive pi gene and segregating for the dominant Lfy gene. The pi gene doubles the number of kernel rows and therefore has the potential to increase the sink size. The Lfy gene
increases the number of leaves above the ear. This past year crosses were made between plants in each population with these genes and elite Stiff-Stalk or Lancaster lines without these genes. Objective 3: Training future plant breeders. Training future plant breeders depends on a undergraduate curriculum that offers opportunities for introduction and training in core copetencies for future plant breeders, including basic genetics and statistics. This past year, introductory courses were taught in both fields.
Impacts
All research is long-term. There were no findings, products, etc. this year that contributed to a significant outcome or impact.
Publications
- No publications reported this period
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Progress 10/01/05 to 09/30/06
Outputs
I)Crossover interactions i)An analysis of muliplte-year and multiple-location yield data of winter wheat was undertaken to determine the frequency and distribution of crossover interactions in the central and southern Great Plains of the U.S. The findings did not support the concept of breeding for local adaptation. ii) Many historical databases of crop yield trials are not ideally suited to studying crossover interactions and their relationship to genotype x year, genotype x location, and genotype x location x year interactions because the genotypes and/or locations change from year-to-year. Therefore, a field study was initiated with 20 corn modern single-cross corn hybrids that will be repeated for at least three years and approximately six locations per year to generate a balanced set of multiple-location, multiple-year yield data. II) New method of generating single-cross hybrids i) Selections were made in a hybrid population of high-yield genotypes in 2005.
These genotypes were identified on the basis of single-plant performance. Selfed progeny of one of these genotypes was sent to a private seed company for the production of several hundred doubled haploids. Progeny from three of the selections were compared to the original hybrid population in field evaluations at two environments in 2006 to more fully determine the eliteness of these selections. ii) Selections were made in a second hybrid population that is more elite than the population from which selections were made in 2005. Over 1500 plants were grown and self-pollinated in a trial where steps were taken to minimize environmental effects that cause variation in plant-to-plant performance. The highest yielding plant had a grain yield of 380 bushels per acre. Evaluation of single-cross hybrid plants in an adjoining plot indicated a broad-sense heritability within a single location of over 60%. III) Yield components A long-term study to investigate the relationship between two grain
yield components, maximum yield per plant under very low plant-to-plant competition and the rate at which this per plant yield declines as plant-to-plant competition increases, was continued. The single population is being selected divergently at approximately 7000 plants per acre and at 37,000 plants per acre. Advanced cycles of these populations were evaluated in 2006 for the first time to determine if differences have resulted for these two components.
Impacts
I) Crossover interactions Each year in the United States, millions of dollars are spent on evaluation of cultivars in regional tests. Understanding the frequency and distribution of crossover interactions is essential to improving the efficiency of this effort. II) New method of generating single-cross hybrids Development of a more efficient method of generating single-cross hybrids will improve and rate of genetic gains. If corn and other key crops are to be used widely for biofuel production in addition to their current uses as human and animal feedstocks, rates of genetic gain will need to be increased to avoid serious shortages and/or increases in commodity prices that would adversely affect the practicality of these multiple uses.
Publications
- Mishra, R., P.S. Baenziger, W.K. Russell, R.A. Graybosch, D.D. Baltensperger, and K.M. Eskridge. 2006. Crossover interaction for grain yield in multi-environmental trials of winter wheat. Crop Sci. 46:1291-1298.
- Baenziger, P.S., W.K. Russell, G.L. Graef, and B.T. Campbell. 2006. Improving lives: 50 years of crop breeding, genetics, and cytology (C-1). Crop Sci. 46:2230-2244.
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Progress 07/01/05 to 12/31/05
Outputs
A key objective is the determination of the feasibility of a new approach to developing hybrid crop cultivars. Meeting this objective depends on generating appropriate seed stocks and on obtaining adequate funding to cover the research costs. Seed stocks were prepared in a summer nursery and additional stocks are being developed currently in a winter nursery. A grant proposal was written and submitted. The potential of this new aproach also depends on the degree to which the performance of different cultivars in field trials conducted in multiple environments change in rank. Rankings of wheat cultivars over a series of environments were analyzed, and the results indicated that changes in ranks were significant. Relationships among testing locations based on these rankings were not consistent across years and were different from relationships based on other methods that have been used in the past to group environments. A second objective of this project is to develop
new types of corn hybrids and to test the feasibility of the commercial potential of these hybrids. Seed of these hybrids have been produced and evaluations will be initiated in the next growing season.
Impacts
Hundreds of millions of dollars are spent annually in the United States on the development of new hybrid crop cultivars. The gain in yield attributable to the continual release of these improved cultivars has been key to keeping U.S. agriculture competitive in the world markets. If this new method increases the efficiency of the development of hybrid cultivars, it will have a significant impact on maintaining U.S. competitiveness in world agricultural markets. Hybrid seed corn costs have risen substantially over the past several years. At the same time, the price received by prodcuers of corn grain has dropped. This situation puts many corn producers, particularly those with average to below average output per land area, in a financial squeeze. Development of alternative hybrids for which seed can be produced at a relatively low cost is important to these producers.
Publications
- No publications reported this period
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