Progress 08/20/03 to 08/19/08
Outputs
Progress Report Objectives (from AD-416) Determine the impact of production practices and selection on seed quality. Approach (from AD-416) We will use germplasm selections grown in two locations differing in production system: conventional vs. sustainable farming. The lines derived from GEM breeding crosses developed in the grain quality traits breeding project of CICGR, ARS. Because the lines have been selected for grain composition through development their composition values have a wider range. Several seed quality tests will be performed in the laboratory. These tests are: standard germination test, saturated cold test, accelerated aging (AA) test, soak test, electrical conductivity (EC) , and fast green. These tests will be used in the calculation of an inbred quality index . Statistical comparisons among genotype and environment will be used to differentiate lines according to seed quality attributes and their ability to withstand sustainable production practices. Significant Activities that Support Special Target Populations From 2003 to 2008, Iowa State University cooperators determined: 1) Seed composition and genetic background affects seed quality. This discovery has highlighted the importance of evaluating seed quality characteristics early in breeding research programs. 2) Seed quality is affected by the production system (conventional vs. organic). 3) Seed produced in organic systems has lower germination and seed vigor. This seed quality difference could be attributed to later spring planting in organic and conventional production systems used to avoid cold soil and pests, thus a shorter growing season. 4) The general combining ability (GCA) effects for seed quality are relatively more important than the specific combining ability (SCA) effects. 5) Although seed quality of the lines varies, corn lines selected for high nutritional value in a conventional production system still have the same high nutritional value when produced in an organic or sustainable production system. 6) The oil content of seeds produced in the low input system was significantly higher than in the conventional system. 7) The additive effects of the inbred are more important to hybrid seed quality than the dominant effects. 8) Early selection for good seed quality characteristics in this group of inbreds could translate to good seed quality in the hybrids. The ADODR monitors activities for the project by periodic phone calls and emails about every two weeks. The ADODR and cooperator are in the same location and see each other frequently where project activities are discussed.
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Progress 10/01/06 to 09/30/07
Outputs
Progress Report Objectives (from AD-416) Determine the impact of production practices and selection on seed quality. Approach (from AD-416) We will use germplasm selections grown in two locations differing in production system: conventional vs. sustainable farming. The lines derived from GEM breeding crosses developed in the grain quality traits breeding project of Dr. Linda Pollak. Because the lines have been selected for grain composition through development their composition values have a wider range. Several seed quality tests will be performed in the laboratory. These tests are: standard germination test, saturated cold test, accelerated aging (AA) test, soak test, electrical conductivity (EC), and fast green. These tests will be used in the calculation of an inbred quality index . Statistical comparisons among genotype and environment will be used to differentiate lines according to seed quality attributes and their ability to withstand sustainable production practices. Significant Activities that Support Special Target Populations This report serves to document accomplishments conducted under a Specific Cooperative Agreement between ARS and Iowa State University. Additional details of research can be found in the parent project 3625-21000-046-00D Breeding High-Quality Corn for Sustainable, Low-Input Farming Systems. Corn seed for organic production will eventually need to be grown organically, thus research is needed to ensure excellent seed quality in organic corn seed production. Twenty high protein breeding genotypes were planted during two growing seasons in conventional and organic nurseries near Ames, Iowa, to produce seeds for laboratory tests. The germination, saturated cold, accelerated aging, and soak test percentages of seeds produced organically were lower than for seeds produced conventionally. Protein, measured by NIR, was unaffected by the production location, but the oil content of seeds produced organically was significantly higher than in the conventional system. Location by genotype interactions for most tests were non significant both years, indicating that genotypes selected for high seed quality in a conventional system will also have high seed quality when grown in a low input, organic system. Seed composition, genetic background, and environment influence seed quality. Plant breeders selecting for improved seed composition seldom select their inbreds for improved seed quality traits. Currently, there is little information on the possible genetic improvement of seed selected simultaneously for both, improved seed composition and vigor. In this experiment, a group of inbreds and their corresponding hybrids selected for high-protein content, white seed color, seedling cold tolerance and high post-accelerated aging field emergence. The mean percentage of standard germination test, saturated cold test, accelerated aging test, soak test, and fast green test for the group of selected high-protein white inbreds were significantly higher than the average values of the corresponding yellow inbred checks. There was genetic variability for seed quality in these sets of high protein white inbreds even after a very intense selection process for improved seed quality traits. GCA effects for seed quality were more important than the SCA effects, indicating that the additive effect of the inbreds was more important than the dominant effect to the final seed quality of the hybrids. Selecting inbreds for high seed quality early in the breeding program is beneficial and important for improving germination and field performance. The ADODR monitors activities for the project by periodic phone calls and emails about progress during the year. These contacts occur at least every two weeks. The ADODR and cooperator are in the same location and see each other frequently where project activities are discussed.
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Progress 10/01/05 to 09/30/06
Outputs
Progress Report 4d Progress report. This report serves to document research conducted under a Specific Cooperative Agreement between ARS and Iowa State University. Additional details of research can be found in the report for the parent CRIS 3625- 21000-046-00D Breeding High Quality Corn for Sustainable, Low-Input farming Systems. This research integrates plant breeding, corn genetics, and seed science. Plant breeders developing new inbred lines with improved grain nutritional value are frequently not aware how their selections impact seed quality. Selecting for increased oil and protein content in the grain sometimes comes at the expense of seed quality. Unanticipated seed quality problems may occur when seeds are multiplied in an alternative location or when lines are crossed to make hybrids. Plant breeders usually select corn in fields cultivated in a conventional manner (i.e., using chemical pesticides and fertilizers to maximize production). Seed quality and
nutritional value of the grain could be different when corn is produced in these high-input systems, rather than in low-input, organic and sustainable crop production systems. The results of this research indicate that seed quality is affected by the production system. Seed produced in organic systems has lower germination and seed vigor. This seed quality difference could be attributed to later spring planting in organic and sustainable production systems used to avoid cold soil and pests, shorter growing season, and greater threat of freezing injury incidence in the fall. Although seed quality of the lines varies, corn lines selected for high nutritional value in a conventional production system still have the same high nutritional value when produced in an organic or sustainable production system. This is an important finding because it means that breeding selections made in a conventional system can be transferred directly to an organic production system. Other aspects of
this on-going research include predicting seed quality of the hybrid from the seed quality of the inbred lines used in the cross; and evaluating the inbred quality index for predicting inbred and hybrid seed quality.
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Progress 10/01/04 to 09/30/05
Outputs
4d Progress report. This report serves to document research conducted under a Specific Cooperative Agreement between ARS and Iowa State University. Additional details of research can be found in the report for the parent CRIS 3625- 21000-046-00D Breeding High Quality Corn for Sustainable, Low-Input farming Systems. This research project will determine if seed quality of high protein corn lines is affected by organic and conventional farming systems. A quality index is going to be determined based on results of laboratory tests performed on seed samples. Correlation of seed quality with other traits, such as variation in protein and oil composition will also be observed. Previous research suggests that chemical composition is influenced by the environment. Seed quality is crucial for a satisfactory crop establishment and is an important part of the process of breeding programs for sustainable farming systems, where varieties are developed in target environments under
restricted conditions.
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Progress 10/01/03 to 09/30/04
Outputs
4. What were the most significant accomplishments this past year? D. Progress Report. This report serves to document research conducted under a Specific Cooperatve Agreement between ARS and Iowa State University. Additional details of research can be found in the report for the parent CRIS 3625- 21000-046-00D Breeding High-Quality Corn for Sustainable, Low-Input Farming Systems. The purpose of this research is to evaluate seed quality attributes of germplasm selected for sustainable agriculture production practices, determine their correlation with other quality traits, and determine the best method of assessing seed quality variations early in the selection process. We characterize seed quality by measuring germination, emergence in cold test, pericarp integrity using Fast Green, cell membrane integrity using Electrical Conductivity of the soaking water, seed vigor using the accelerated aging test and the soak test. Values of these tests are used to calculate an
index in order to rank germplasm according to seed quality. In the summer of 2003, eighty high-protein synthetic lines were planted under organic and conventional production systems. In September/October 2003, ears were harvested at physiological maturity (30 % moisture content or black layer formation) and dried artificially with forced air to preserve maximum seed quality. Seed were shelled and stored in a controlled temperature room at 10 DGC. Chemical composition of the seed was determined using NIR to assess seed composition differences of seed grown under these two environments. A graduate student was identified to conduct the research. She started her graduate program on January 2004. Seed quality evaluations were initiated during the Spring 2004, as well as the second year of field plantings (Summer 2004). Trials are carried out on farms of Practical Farmers of Iowa members, in conjunction with breeding trials carried out through the USDA-ARS 'Breeding High-Quality Corn
for Sustainable, Low-Input Farming Systems' project that collaborates with Iowa State University (ISU), Michael Fields Agricultural Institute, and Practical Farmers of Iowa (PFI). Previous work by this research team demonstrated that seed quality is affected by seed composition, genetic background, and production environment. Research results also showed that seed quality decreases when seed are produced under a sustainable agriculture system. Germination percentage and cold emergence (saturated cold test) results of corn seed produced in a sustainable agriculture system are significantly lower than seed produced using conventional seed production practices. This lower seed quality corn also emerged poorly when planted early in the field. Statistical comparisons among genotype and environment are used to differentiate lines according to seed quality attributes and their ability to yield high quality seed under sustainable production practices. Results are compared to early field
emergence and final stand of the seed planted in conventional and sustainable production fields. Understanding the seed quality attributes that can minimize these differences is essential for providing producers and farmers with improved nutritional value, high seed quality corn varieties adapted to sustainable farming systems.
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