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GEM
- 2005 Annual Report I. 2005 PROGRAM ACCOMPLISHMENTS AND HIGHLIGHTS Germplasm releases and development:
Pathology/Entomology: Pathology and entomology collaboration from the private and public sectors included extensive data collection on GEM lines and breeding crosses for anthracnose, Northern Leaf Blight races 1 and 2, Southern Leaf Blight, Stewart’s Wilt, Goss’s Wilt, Gray Leafspot, common and southern rust, Fusarium ear rot, Aspergillus, European Corn Borer, Corn ear worm, and corn root worm. Public Cooperator Reports are available at this meeting. Special recognition and thanks to the extensive efforts of private GEM Cooperators Pioneer Hi-Bred International, and Professional Seed Research. Highlights of important accomplishments in 2005 include:
Quality Traits:
Ames Location Highlights:
GEM Line Recommendations for Midwest for 2006 Release: Thirteen GEM lines were selected in 2005 having 2-years of favorable data for yield, Y/M, and resistance to stalk and rot lodging. The lines are from a diverse group of races from accessions originating from Argentina, Brazil, Peru, Thailand, and Uruguay. Table 1. Recommended Ames GEM Lines for 2006 Release
Raleigh, NC Location Highlights (from Dr. Major Goodman): This subproject is concerned with nine aspects of the overall GEM effort. (1) The development of GEM families from breeding crosses. (2) Making topcross seed of the families. (3) Setting up appropriate experiments to compare the topcross families with commercial and experimental checks. (4) Providing seed for these experiments to 15 additional GEM collaborators. (5) Growing the experiments ourselves at several locations. (6) Analyzing and summarizing our own and our collaborators data. (7) Selecting the better materials for subsequent‑year trials. (8) Increasing seed of better families, providing it to Ames and other GEM cooperators and to the NCRPIS. (9) Sampling allelic diversity from representative races not encompassed by GEM yield-trial efforts. 144 entries (out of 1086 tested) have been advanced from first year to second year trials in 2005, and 27 entries (out of 216 tested) advanced from second year to third year testing. In 2005, 12,421 yield trial plots were coordinated through Raleigh (4,013 planted at NC State locations). Approximately, 885 nursery rows, and 1020 isolation block rows were planted in 2005 at Raleigh. Nursery work involves 10 new breeding crosses and 10 additional breeding crosses derived from tropical inbred lines. In 2005, 19 GEM families were recommended to GEM Cooperators and provided from stocks furnished to Ames; five additional families were recommended and provided directly from Raleigh. We have continued routine screening of available tropical lines, as so little data are available to choose among them for use in GEM or other research. A summary of some of that work has been accepted as an invited article for the 50th anniversary issue of Maydica. In 2004, the effort to evaluate GEM breeding crosses for yield per se was continued as part of an overall effort to evaluate new material. Data from that study revealed a great spread in yield potential and heavily influenced our choices for 2005 nursery work. Direct tests of Breeding Cross F1s were continued in 2005, and data was obtained for 5 locations. The following crosses look reasonably promising:
In contrast, the following Breeding Cross F1s look as though they should be avoided:
Check performance and CVs are listed below:
In addition, a group of Breeding Cross F2s were tested. While testing F2s is a more questionable endeavor, nevertheless,
look like keepers, while
do not. II. PUBLIC COOPERATOR WITH SPECIFIC COOPERATOR AGREEMENTS (SCA) IN 2005: Eight university and one USDA-ARS projects were funded in 2005 for a total of $207,000. Table 2. Public Cooperators Supported In 2005
Total $207,000 A short summary of key highlights from each SCA report, and one volunteered research report is included below. Please see the complete reports under Public Cooperator Reports 2005 on GEM website for details about methods, pedigrees, and data tables. Martin Bohn, University of Illinois: Evaluation of GEM germplasm for multiple insect resistance and fumonisin concentration. This project is a continuation of the study begun in 2003 with the objective to develop and evaluate germplasm, and study the genetic basis of resistance to Western Corn Rootworm (WCR), European Corn Borer (ECB), and the association of insect resistance to fumonisin concentration, a mycotoxin produced by Fusarium sp. The project includes four experiments for germplasm screening, and three sub-projects for germplasm development. (It is not possible to discuss all the experiments and development work in this summary-see full report) Testcrosses were produced through collaboration with Pioneer and Syngenta and a generalized lattice experiment planted and infested with first and second generation ECB, and a separate experiment planted under a WCR trap crop area. Traits measured included root damage ratings (RDR), stalk damage ratings (SDR), root damage rating (RDR), and agronomic traits. Significant differences among genotypes were reported for RDR, SDR, and RDR. In general, GEM nSS topcrosses had less root damage due to WCR than GEM SS x testers. Test crosses with GEM lines DKXL212.N11a01-05-1-2 (RDR = 0.69) and DKXL212.N11a01-02-5-2 (RDR=0.98) showed the lowest RDR. Five GEM:NSS-TCs displayed significantly (P < 0.05) less root damage than the commercial check hybrids. Two genotypes having significant SCA effects for reduced root lodging, and having higher levels of WCR resistance were AR17056:N2025-522-1-B-B-B x AR17056:N02025 select #5, and AR17056:N2025-522-1-B-B-B x Mo12. The former genotype is GEM x GEM and is therefore of particular interest. In another factorial cross experiment conducted through support of AgReliant, the AR17056:N025-522 genotype showed the lowest average RDR across all cross combinations. Based on the observation that root lodging and RDR are significantly correlated, root lodging was used as a criterion for selection in early generations involving a set of 162 new S2 lines. The enhanced vigor of testcrosses provides a more accurate assessment of WCR resistance than inbred lines particularly under high infestation levels of the insect. Mark Campbell, Truman State University: Development and utilization of GEM based amylomaize hybrids and the identification of amylose modifying genes through QTL analysis. The objective of this study is a continuation of the research to develop amylomaize VII hybrids from GEM derived lines and to explore the potential of using this material for the production of high-amylose starch. In 2005, our efforts included collaboration with two other labs: (i) Dr. Yang Yen at South Dakota State (SDSU) for the development of a mapping population for high amylose modifiers, and, (ii) Dr. Jay-lin Jane at Iowa State to explore applications for high amylose maize for resistant starch. We reported previously that GUAT209:S13 was an important source of amylose modifiers to enhance development of amylomaize VII germplasm (GEM web site Public Cooperator Reports 2002-2004). Forty six polymorphic markers were identified among the 10 chromosomes in the mapping population H99 x GUAT209:S13//OH43ae/H99ae. Our goal is to identify at least 85 markers in the near future. In 2005, grain samples were collected from 300 F2 ears grown in MO to collect phenotypic data on starch amylose values, and SSR work to complement this effort being done at. SDSU. In Dr. Jane’s lab, three amylomaize VII selections derived from GUAT209:S13//OH43ae/H99 were analyzed for amylose and resistant starch using the AOAC method for total dietary fiber. The results were promising and indicative that high levels of amylose above 70% were correlated with resistant starch content (see complete report of Dr. Jane on http://www.public.iastate.edu/~usda-gem/ Second year yield results of an amylomaize yield trial was conducted by the GEM Project in Ames, IA, and at our location in Novelty, MO. The location in Novelty was under severe stress but averaged in the 2 year data. The average yield among the SS tester hybrids was 98 bushels. A normal commercial (non-amylose) check hybrid yielded 125 bushels which was not unexpected. In general, many of the GEM amylomaize hybrids outperformed the high amylose tester hybrid (68 bushels). One hybrid, CHIS775:N1912-519-1-B-B///GUAT209:S13//OH43ae/H99ae////SS tester, had an amylose content of 69.3% and yielded 100 bushels. Michael Clements, USDA-ARS, Mississippi State, MS: Evaluation of GEM testcrosses for yield and resistance to Aspergillus ear rot and aflatoxin accumulation in grain in the southern US. Aflatoxin continues to be an important problem in grain markets every year. Although sources of resistance have been identified in public germplasm the majority of this material is usually very late, poor as lines per se, and have low combining ability. The objectives of this study were to evaluate testcrosses developed from 145 GEM lines x Holdens’ testers, LH195 and LH210. Agronomic traits evaluated included emergence, silking and anthesis expressed as modified growing degree units (MGDU), root and stalk lodging, stay green, yield, and grain moisture. In a second study, 16 GEM lines selected from our 2004 study were evaluated again for Aspergillus ear rot, and aflatoxin accumulation in the grain. The results of the 145 entry agronomic trial indicated that emergence, MGDU to silking, MGDU to anthesis, and root lodging were affected significantly (P < 0.05) by genotype within trials in which LH195 or LH210 was the common tester. Emergence varied from 7 to 26 plants row-1 (mean 20 plants row-1) and from 7 to 25 plants row-1 (mean 19 plants row-1) in trials within which LH195 or LH210 was the common tester, respectively. Greatest emergence was observed from hybrids developed with 2250-01_XL370A_S11_F2S4_9214-Blk21/00-sib-B (GEMS-0020), in trials within which LH195 or LH210 was the common tester. Stalk lodging, staygreen, and yield were not affected significantly by genotype (P > 0.05) in trials within which LH195 or LH210 was the common tester. Yields ranged from 62 to 192 bushels per acre (mean=138) for the LH195 tester, and from 85-196 (mean 143). In the aflatoxin study, severity of Aspergillus ear rot was affected significantly (P<0.05) by genotype in trials within which LH195 or LH210 was the common tester. Severity of Aspergillus ear rot ranged from 2 to 22% (mean 9%) or from 2 to 23% (mean 11%) of the ear rotted in trials within which LH195 or LH210 was the common tester, respectively. Least Aspergillus ear rot was observed on the resistant check, Mo18W/Mp313E. Six GEM lines had severity of Aspergillus ear rot that did not differ significantly from ear rot on Mo18W/Mp313E in the LH195 or LH210 trial. GEM lines with severity of Aspergillus ear rot that did not differ significantly from least ear rot in both trials were 2250-01_XL370A_S11_F2S4_9214-Blk21/00-sib-B (GEMS-0020), and 2258-03_XL380_S11_F2S4_71/97_Bulk/98-sib-B (GEMS-0030). Data for aflatoxin concentration in grain from this experiment is not yet available. Jim Coors, University of Wisconsin: Development of inbreds, hybrids, and enhanced GEM breeding populations with superior silage yield and nutritional value. In 2005, we continued to evaluate silage yield and nutritional value of GEM topcrosses. An important check hybrid in these studies was top crossed with the Wisconsin release, W605S, a non-stiff stalk line derived from the GEM breeding cross, AR17026:N1019. Five trials were conducted at two locations (Arlington and Madison, WI). Climatic conditions at both locations had severe drought stress which lead to low forage yields with excessive root and stalk lodging. Twenty-four new GEM topcrosses selected from grain trial results of the GEM Project were evaluated in the trial GEMNEW. Five of the 24 topcrosses exceeded 9.49 tons/acre (the check mean), with two GEM pedigrees greater than 10 ton/acre (AR16026:S17-104-1-B-B x LH283, and FS8B(T):N11a-322-1-B x LH200). W605S x LH244 yielded 9.62 tons/acre in the GEMNEW trial which exceeded the check mean. Other re-test non-stiff stalk GEM lines were evaluated in separate trials on two SS testers, HC33 and LH198. Most of the topcrosses in these two trials were derived from the 50% tropical breeding cross, BR52051:N04. Overall, topcrosses derived from BR52051:N04 had excellent lodging scores when crossed to HC33 or LH198. Seven hybrids exceeded the check mean in the HC33 trial, and two hybrids in the LH198 trial exceeded the check mean. In both trials a related line to W605S also exceeded the check means. Stiff stalk related GEM lines were evaluated on two non-stiff stalk testers, LH279 and LH287. Both trials had severe lodging and drought, but nonetheless the yield of 11 LH279 topcrosses, and 18 LH287 topcrosses exceeded the mean of the four checks. The line CUBA164:S2012-235-1-B-21 had excellent performance on both testers. Nutritional evaluation will be complete in about one month and posted to http://www.silagebreeding.agronomy.wisc.edu. Major Goodman, North Carolina State University: Conducting, coordinating, and developing inbreds from the Southern GEM trials using 50%-tropical maize germplasm. See full report under Raleigh, NC highlights. Data analysis is still in progress and recommendations will be available in mid-January on the GEM website. Jim Hawk, University of Delaware: Inbred line development and hybrid evaluation in GEM breeding crosses. Ninety-six GEM breeding crosses were evaluated for adaptability, maturity, disease, and other traits as part of a collaborative experiment with the GEM Project in Ames, IA, and Mycogen Seeds in Mount Vernon, Indiana. The important leaf diseases in Delaware in 2005 were gray leaf spot and anthracnose stalk rot. Twelve breeding crosses were identified as being well adapted to Delaware and were recommended for further development per se, or for making 25% breeding crosses. Final recommendation for future breeding will be made pending on the combined results from Ames and Indiana. Inbreeding was initiated on three new stiff stalks, and two non-stiff stalk breeding crosses. A collaborative breeding methods experiment with the GEM Project in Ames was continued for the second year with the objective to compare the GEM protocol (pedigree method), single seed descent, and a mass selection procedure using two GEM populations. The two populations used were FS8A(T):N1804, and AR16026:S1716. It was found that AR16026:S1716 was very to herbicide (sulfonylurea) and had to be dropped from the study. Yield tests were conducted on 215 SS lines x LH287, and 249 nSS lines x Pioneer tester. The best yielding lines were derived from DKXL212:S0912. The top 10-20% of the lines will be advanced. A significant accomplishment in 2005 was the release of DE6 having 4% greater protein than B73 over a 3 year average. In addition, DE3 and DE4 have been Crop Science registered (see Crop Sci. 45:2669-2670.) Jay-lin Jane, Iowa State University: Value added utilization of GEM normal and high amylose line starch. The objective of this research is to characterize starch and potential of value added utilization of these lines. We were interested in identifying germplasm with highly digestible starch (for animal feeding advantages), and secondly to find lines with resistant starch properties. Resistant starch is receiving increased attention for human nutrition, diabetes, and obesity. The sources of germplasm consisted of (1) normal starch GEM lines that were identified with interesting values determined by Differential Scanning Calorimetry (DSC) in the USDA-ARS lab in Ames, IA, and (2) starch isolated from high amylose maize obtained from Dr. Mark Campbell, Truman State University. For the normal starch lines, GEM genotypes having low or high gelatinization temperatures, and low or high percent retrogradation were chosen for their potential for digestible starch. Enzyme digestibility tests were run using porcine pancreatic alpha amylase. Two promising GEM lines were identified with 65% digestibility: DKB844:S1601-289, and AR17056:N2025-574. The amylopectin branch chain lengths were analyzed to understand how starch structure affects digestibility. The results indicated that highly digestible starch was in general associated with shorter branch chain length. The lines were increased by self pollination in the Ames, IA nursery by the GEM Coordinator, and crosses were made for future yield trials and digestible starch analysis of the F1 hybrid. For the high amylose lines, resistant starch (RS) content was measured by the AOAC method for dietary fiber content, and amylose content was measured by gel permeation chromatography (GPC). The pedigrees studied included 3 amylomaize VII lines derived from GUAT209:S13//OH43ae/H99ae from Truman State University (see report by Campbell). Amylose content was between 86.1-88.4% for these 3 lines. Inbred checks H99ae, OH43ae, B89ae, and B84ae were also run for comparison of amylose levels and RS content. The 3 GEM lines had RS values between 39.4-43.2% vs only 11.5-19.1% for the 4 inbred checks. The correlation coefficient for % amylose and RS was highly significant, R= 0.89**. Amylopectin from RS had more long branch chains (DP>37), but displayed similar thermal properties for onset of gelatinization temperature. RS had a broader range of gelatinization temperature and starch granules were highly resistant to boiling temperatures. Dr. Jane’s lab plans to process additional high amylose GEM lines to further increase RS content with potential for manufacturing value-added health foods. Paul Scott, USDA-ARS, Ames, IA: Identification of germplasm with superior amino acid content. (volunteered report from Public Cooperator) Approximately 70 GEM lines per year have been analyzed for the past 4 years for nutritionally limiting amino acids tryptophan, lysine and methionine. The GEM material includes lines developed in Ames, Raleigh, and the University of Delaware. All analyzed samples were from self pollinated seed of the GEM nursery grown in Ames each year. We use a microbial method (Scott et al., Maydica 49:303-311) that is suitable for ranking samples. The inbred line B101 was included as a high methionine check and B45o2 was included as a high lysine and tryptophan check. B73, Mo17 and B73xMo17 were included as normal checks. In the 4 year analysis the methionine content of one public released GEM entry GEMS-0030 (2258-03_XL380) was not significantly different than the high methionine check, and the lysine content of one University of Delaware entry (DKXL212:N11a-139) was not significantly different than the high lysine check. For the new entries in 2005 (1 year data), two lines had significantly higher methionine than the high methionine check. In summary, GEM germplasm has been identified that shows promising levels of methionine, lysine and overall quality. It will be important to evaluate the protein content of this germplasm and to conduct multiyear evaluations on germplasm new to the study. Several entries from these studies have been released as public available GEM lines. Margaret Smith, Cornell University: Anthracnose stalk rot resistance from exotic maize germplasm. The anthracnose stalk rot study at Cornell is a multi-year inbred development effort to identify and release lines from GEM breeding crosses having high levels of resistance to stalk rot and good yield potential. Results of the 1995 per se breeding cross evaluations for anthracnose identified four breeding crosses that we selected for future development. All of them were 25% exotic temperate, with one population being stiff stalk (SS) related, CH04030:S0906, and the others non-stiff stalks (nSS), FS8B(T):N1802, AR01150:N0406, and GOQUEEN:N1603. Resistant families were developed through cyclic inoculation of families beginning at the S1 level of breeding and proceeding to S6. Test crossing was initiated at the S2 stage and continued through the advanced S5-S6. Yield and resistance data was used for selection and advancing the most promising families. On the basis of yield trials conducted in NY State in 2003 and 2004, with subsequent anthracnose ratings the best lines from the SS and nSS families were identified. Stiff stalk derived inbreds were generally not as resistant to anthracnose as nSS families. The best inbreds from the SS family CH04030:S0906 were inbreds 195, 250, 253, and 254. These lines have potential for resistance per se and in test crosses with reasonable yield potential. From the nSS families, FS8B(T):N1802 selections had the highest number of promising entries for resistance with three lines also had promising yield potential (222, 259, and 263). Several interesting lines were also identified from the other nSS’s AR01150:N0406 and GOQUEEN:N1603. A new nSS synthetic was created by intercrossing the best lines from the three nSS populations in this study. The yield data from 2005 has not been analyzed. We expect to release lines in 2006 pending data analysis. Wenwei Xu, Texas A&M University: Characterization and utilization of GEM breeding crosses, top crosses, and advanced lines for drought tolerance, grain mold, and corn ear worm resistance. The objectives of this project include (1) conducting field trials of 130 topcrosses under abiotic stress conditions at 4 locations in the High Plains, and 3 locations in south Texas, (2) assay aflatoxin of 10 hybrids involving GEM lines, (3) advance and characterize inbreds derived from GEM breeding crosses, (4) conduct second year evaluation of 40 GEM breeding crosses, and (5) conduct second year evaluation of 16 recommended GEM lines for abiotic stress. Results from objectives 1, 2, and 5 are pending analysis such as aflatoxin assays, and trial data from several trial locations. Our preliminary study of 2005 yield trials are supportive of 2004 results for high yielding lines derived from five GEM breeding crosses, AR03056:N0902, SCROGP3:N2017, SCROPG3:N1411a, FS8A(T):N1801, and DK888:N11. One pedigree, SCROGP3:N1411a-1 x B110 in 2004, and crossed to LH200 in 2005 is showing outstanding yield potential both years. An official release proposal of this line will be forthcoming in early 2006. Results of 2 year breeding cross data under abiotic stress under 50% ET and V-10 stress identified the following as being best: AR16026:N1210, AR13026:N08a04, BR52051:N0417, BR51721:N2012, CML323:N15 (one year data), UR13085:N0204, UR13010:N0613, and UR11003:S17b. It was reported that more ears per plant, stay green, and mold resistance could be indicators for good performing breeding crosses. Under a well irrigated breeding cross trial in Lubbock in 2005, the following breeding crosses were not significantly different in yield than the means of the commercial checks: UR13010:N0613, CML323:N15, AR17056:S19, UR11003:S17b, NS1:S08, UR13085:N0204, UR05071:S04, AR17056:S12, and AR16024:N1210. Two breeding crosses in the same 2005 study had significantly less corn ear worm penetration than the mean of the test: UR05071:S04 and GUAT209:N11c. No significant differences were found for grain mold damage among the entries. III. TSG ACCOMPLISHMENTS & HIGHLIGHTS: The TSG held their August meeting in Lubbock, TX and participated in a joint field day of GEM with the Texas A&M Agricultural Experiment Station. Hosting the meeting in Lubbock was Dr. Wenwei Xu, and Experiment Station Director, Dr. Jaroy Moore. An important accomplishment of the TSG in 2005 was the draft formulation of By-laws in August with a final approved version in November. The GEM Mission Statement was also revised by a TSG sub-team and approved by the entire TSG during the August 19 meeting.
IV. PERSONNEL UPDATE: Ames: USDA-ARS Plant Introduction Unit
Fred Engstrom was hired as GEM Technician in August 2005. Fred’s extensive experience with the operation, data collection, and transport of two-plot combines will be an important asset to GEM. Raleigh: USDA-ARS Plant Science Research Unit
NC State University Dr. Major Goodman, William Neal Reynolds and Distinguished University Professor V: IN KIND SUPPORT MIDWEST GEM PROJECT IN 2005: In kind support nursery support to the GEM Project in 2005 was reduced substantially from the support level of 2004 (4,640 rows in 2004 vs. 2,300 rows in 2005). This was mostly due to company consolidations, and to a lesser extent internal resource management by cooperators. In anticipation of reduced nursery support, GEM increased nursery work by increasing the number of breeding crosses worked in Ames to 18 (vs. 12 in 2004). GEM project leadership understands that company consolidations and sound resource management are a natural process of the agricultural community, and essential part of all business. We extend are deepest appreciation to those cooperators who agreed to increase their level of in kind support in 2005. Table 3. Private In-Kind Nursery Support – Summer 2005
Table 4. Private In-Kind Support – Winter 2005-2006
Table 5. Private Cooperator Yield Trials 2005
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