Published online 26 August 2005
Published in Crop Sci 45:2005-2007 (2005)
© 2005 Crop Science Society of America
677 S. Segoe Rd., Madison, WI 53711 USA
CROP BREEDING, GENETICS & CYTOLOGY
Transgressive Segregation for Oleate Content in Three Soybean Populations
Jessie L. Alta,
Walter R. Fehra,*,
Grace A. Welkea and
J. Grover Shannonb
a Dep. of Agronomy, Iowa State Univ., Ames, IA 50011-1010
b Dep. of Agronomy, Univ. of Missouri Delta Center, Portageville, MO 63873
* Corresponding author (wfehr{at}iastate.edu)
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ABSTRACT
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Increased oleate content of soybean [Glycine max (L.) Merr.] oil may be useful for food and industrial applications requiring increased oxidative stability. The objective of this study was to determine if transgressive segregates for oleate content could be found in crosses between three mid-oleate lines: FA22 from Iowa State University, N98-4445A from the USDA-ARS/North Carolina State University, and M23 from Saga University, Japan. Single-cross populations of FA22 x M23, FA22 x N98-4445A, and N98-4445A x M23 were developed. Plants with significantly greater oleate than the highest oleate parent were observed in the three populations in the F2 and F3 generations. For the F3:4 lines grown in Puerto Rico, there were four lines with significantly greater oleate than the highest parent in the cross FA22 x M23, one line in FA22 x N98-4445A, and 27 lines in N98-4445A x M23. The F3:4 line with the greatest oleate content had 689 g kg–1 in the population FA22 x M23, 672 g kg–1 in FA22 x N98-4445A, and 730 g kg–1 in N98-4445A x M23 compared with 542 g kg–1 for FA22, 589 g kg–1 for N98-4445A, and 583 g kg–1 for M23. Transgressive segregates from the populations should be useful as parents in a breeding program to develop cultivars with elevated oleate content.
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INTRODUCTION
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SOYBEAN OIL with increased oleate content may be useful for food and industrial applications (Wilson, 2004). M23 is a mutant soybean line with elevated oleate content developed by x-ray irradiation of dry seeds of ‘Bay’, a cultivar with normal oleate content (Buss et al., 1979; Rahman et al., 1994). In the M2 generation, M23 had an oleate content of 461 g kg–1 compared with 223 g kg–1 oleate for Bay. Takagi and Rahman (1996) proposed a single locus controlling oleate in M23 with two alleles, Ol controlling normal oleate and ol controlling mid-oleate. Kinoshita et al. (1998) confirmed that the elevated oleate associated with the ol allele in M23 was conditioned by a deletion at the Fad2-1 locus, an 
-6 fatty acid desaturase. Alt et al. (2005) found that the oleate content of lines homozygous for the ol allele was significantly influenced by modifying genes.
FA22 is a line with mid-oleate content developed by Iowa State University. N98-4445A is a mid-oleate line developed by the United States Department of Agriculture and North Carolina State University (Wilson, 2004). FA22 and N98-4445A do not have the deletion of Fad2-1 present in M23 (Alt et al., 2005).
The objective of this study was to determine if the alleles conditioning mid-oleate in FA22, N98-4445A, and M23 were sufficiently different to result in transgressive segregation for the trait. If transgressive segregates were found, they could be useful for elevating the oleate content of soybean in a cultivar development program.
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MATERIALS AND METHODS
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FA22, N98-4445A, and M23 were crossed during July 2002 at the Iowa State University Agricultural Engineering and Agronomy Research Center located near Ames, IA, to form three single-cross populations. FA22 was of Maturity Group 0, N98-4445A of Maturity Group IV, and M23 of Maturity Group V.
The F1 seeds from the crosses FA22 x M23, FA22 x N98-4445A, and N98-4445A x M23 and seeds of each parent were planted October 2002 at the Iowa State University-University of Puerto Rico soybean breeding nursery at Isabela. Hybrid F1 plants were confirmed with simple-sequence repeat markers by comparison with the parents.
From each population, 200 random F2 seeds and 10 seeds of each parent were planted during February 2003 at Isabela on a Coto clay (very-fine, koalinitic, isohypethermic, Typic Haplorthox). All plants of each population and the parents were harvested and threshed individually. A five-seed bulk sample from each plant was analyzed for fatty ester composition. All fatty ester analyses for this study were performed according to the procedure of Hammond (1991). The F2 plants from each population with >600 g kg–1 oleate were selected for further evaluation as F2:3 lines.
During May 2003, 61 F2:3 lines of FA22 x M23, 53 lines of FA22 x N98-4445A, 39 lines of N98-4445A x M23, and the parents were planted in a randomized complete-block design. One replication was planted 22 May at each of two locations near Ames, IA, at the Agronomy Farm and the Burkey Farm, on a Nicollet loam (fine-loamy, mixed, superactive, mesic Aquic Hapludoll). One replication was planted 29 May at the University of Missouri–Columbia Delta Research Center Lee Farm near Portageville, MO, on a Tiptonville silt loam (fine-silty, mixed, superactive, thermic, Oxyaquic Argiudoll). Plots at Ames were a single row, 0.76 m long, with 1.02 m between rows. Hill plots at Portageville were spaced 0.91 m between plots within a row and 0.76 m between rows. The seeding rate for all plots was 10 seeds. After the plants in each plot matured, they were harvested and threshed individually. N98-4445A, M23, and some segregates from each cross were killed by frost at the two Iowa environments, but all plants matured before frost at Portageville. A five-seed bulk from each plant was analyzed for fatty ester content.
All F3 plants with greater oleate than the highest parent plant of the population at that environment were considered transgressive segregates and selected for further evaluation as F3:4 lines. During January 2004, 35 F3:4 lines of FA22 x M23, 28 lines of FA22 x N98-4445A, 47 lines of N98-4445A x M23, and the parents were planted in two replications of a randomized complete-block design at the Illinois Crop Improvement Association near Ponce, PR, on a San Antón sandy clay loam (fine-loamy, mixed, superactive, isohyperthermic Cumulic Haplustolls). Plots were a single row 0.91 m long planted on raised beds with 0.42 m between the two rows on a bed and 1.35 m between rows on adjacent beds. The seeding rate in all plots was seven seeds. Four random F4 and parent plants were harvested and threshed individually from each plot. A five-seed bulk from each plant was analyzed for fatty ester composition.
The 12 F3:4 lines from the cross N98-4445A x M23 which had all four F4 plants with >700 g kg–1 oleate were selected for further evaluation. From each selected F3:4 line, the two F4 plants with the greatest oleate content were evaluated as F4:5 lines. The evaluation was done at the University of Missouri–Columbia Delta Center Lee Farm because the parents and their progeny were not expected to reach maturity before frost at Ames. On 1 June 2004, the 24 F4:5 lines, the parents, ‘Pana’, and ‘Hutcheson’ were planted in two replications of a randomized complete-block design. Pana (Maturity Group III) and Hutcheson (Maturity Group V) have normal oleate content. Plots were 0.61 m long and the row spacing was 0.76 m. At maturity, four random plants from each plot were harvested and threshed individually. A five-seed bulk of each plant was analyzed for fatty ester content.
Standard deviations were computed for the F2, F3, and parent plants. For the F3:4 and F4:5 lines, an ANOVA was computed for all fatty esters by the general linear model using SAS software (SAS Institute, 1999). Replications were considered random effects and genotypes were considered fixed effects. Lines that differed from the parents by more than the least significant difference at P = 0.05 were considered to be transgressive segregates for oleate content.
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RESULTS AND DISCUSSION
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The oleate content of the parents was strongly influenced by the environment in which they were grown (Table 1). Oleate content for M23 and N98-4445A was lowest when grown at Ames and highest when grown at Isabela. M23 and N98-4445A did not mature before frost at Ames, but they matured normally at Isabela and Portageville. Oleate content of FA22 was less variable among environments because it matured before frost at Ames. Thomas et al. (2003) found that oleate concentration in soybean increased with higher temperatures during seed development. Because of the influence of environment, the parent of a population with the greatest oleate at an environment was used to determine transgressive segregation in a population.
Transgressive segregates were observed in the F2 and F3 generations of the three populations (Table 1). There were F2 and F3 plants with >700 g kg–1 oleate at Portageville and Isabela, but not at the Iowa environments (Table 1). At Isabela, FA22 x M23 had 11 F2 plants with >700 g kg–1 oleate, FA22 x N98-4445A had two plants, and N98-4445A x M23 had six plants. At Portageville, there were 11 F3 plants with >700 g kg–1 oleate in FA22 x M23, 13 plants in FA22 x N98-4445A, and three plants in N98-4445A x M23.
Four F3:4 lines in FA22 x M23 and one F3:4 line in FA22 x N98-4445A were transgressive segregates, but none of the lines had >700 g kg–1 oleate. The fatty ester content of the five greatest oleate lines from each population is shown in Table 2. There were 27 F3:4 lines in the cross N98-4445A x M23 that were significantly different than the parents, of which 12 had >700 g kg–1 oleate. Lines of N98-4445A x M23 with > 700 g kg–1 oleate were further evaluated at Portageville by progeny testing the two F4 plants from each of the lines with the greatest oleate content.
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Table 2. Fatty ester content of the five F3:4 lines with the greatest oleate content from each of three soybean populations and the parents of the populations at Ponce, PR, in 2004.
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The F4:5 progeny from seven of the 12 F3:4 lines selected in Puerto Rico had significantly greater mean oleate content than either parent at Portageville (Table 3). Of the 14 F4:5 progeny from those seven F3:4 lines, 11 had significantly greater mean oleate content than either parent. The increase in oleate for the transgressive segregates was associated primarily with a decrease in linoleate. The contents of palmitate, stearate, and linolenate in the transgressive segregates were similar to one of the two parents.
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Table 3. Fatty ester content of seven F3:4 soybean lines from the cross N98-4445A x M23 that had significantly greater mean oleate content than the parents grown at Ponce, PR, in 2004 and their two F4:5 progeny grown at Portageville, MO, in 2004.
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The transgressive segregation observed in all the populations indicated that FA22, N98-4445A, and M23 differed for some of the alleles that condition their mid-oleate content. Oleate content in M23 is conditioned in part by a deletion at the Fad2-1 locus, which is not present in FA22 and N98-4445A (Kinoshita et al., 1998; Alt et al., 2005). The transgressive segregates found in the populations should be useful in a breeding program to develop cultivars with increased oleate content.
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ACKNOWLEDGMENTS
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The authors thank Silvia Cianzio for growing the F1 and F2 plants at Isabela, PR.
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NOTES
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This journal paper of the Iowa Agric. and Home Econ. Exp. Stn., Ames, IA, Project 3732 was supported by the Hatch Act, State of Iowa, Iowa Soybean Promotion Board, Raymond F. Baker Center for Plant Breeding, and the United Soybean Board.
Received for publication December 1, 2004.
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REFERENCES
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- Alt, J.L., W.R. Fehr, G.A. Welke, and D. Sandhu. 2005. Phenotypic and molecular analysis of oleate content in the mutant soybean line M23. Crop Sci. 45(5):1997–2000 this issue.[Abstract/Free Full Text]
- Buss, G.R., T.J. Smith, and H.M. Camper, Jr. 1979. Registration of Bay soybean. Crop Sci. 19:564.[Free Full Text]
- Hammond, E.G. 1991. Organization of rapid analysis of lipids in many individual plants. p. 321–330. In H.F. Linskens and J.F. Jackson (ed.) Modern methods of plant analysis. vol. 12. Springer-Verlag, Berlin.
- Kinoshita, T., S.M. Rahman, T. Anai, and Y. Takagi. 1998. Genetic analysis of restriction fragment length polymorphism on the fatty acid synthesis in soybean mutants and their progenies: II. High oleic acid mutants with two microsomal -6 fatty acid desaturase cDNAs as probes. Bull. Fac. Agric. Saga Univ. 83:37–42.
- Rahman, S.M., Y. Takagi, K. Kubota, K. Miyamoto, and T. Kawakita. 1994. High oleic acid mutant in soybean induced by X-ray mutation. Biosci. Biotech. Biochem. 58:1070–1072.
- SAS Institute. 1999. SAS/STAT user's guide. v. 8.2, 1st ed., vol. 2. SAS Inst., Cary, NC.
- Takagi, Y., and S.M. Rahman. 1996. Inheritance of high oleic acid content in the seed oil of soybean mutant M23. Theor. Appl. Genet. 92:179–182.[CrossRef][ISI]
- Thomas, J.M.G., K.J. Boote, L.H. Allen, Jr., M. Gallo-Meagher, and J.M. Davis. 2003. Elevated temperature and carbon dioxide effects on soybean seed composition and transcript abundance. Crop Sci. 43:1548–1557.[Abstract/Free Full Text]
- Wilson, R.F. 2004. Seed composition. p. 621–677. In H.R. Boerma and J.E. Specht (ed.) Soybeans: Improvement, production, and uses. 3rd ed. Agron. Monogr. 16. ASA, CSSA, and SSSA, Madison, WI.
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ABSTRACT
INTRODUCTION
