Environmental Effects on Soybean with Modified Phosphorus and Sugar Composition

Abstract

Development of soybeans [Glycine max (L.) Merr.] with modified phosphorus (P) and sugar composition adds value to soybean meal. The identification and release of the soybean line V99‐5089 with a mutation in the D‐myo‐inositol 3‐phosphate synthase 1 gene (MIPS1) provides a germplasm source that dually enhances both P and sugar composition of soybeans. An evaluation of the recombinant inbred line population from the cross of V99‐5089 × Essex was completed at three environments in 2 yr. Phenotypic selection for modified composition was slightly more effective than marker‐assisted selection with the Satt453 marker, which was 87% efficient. In the mutant lines, a significant genotype × environment interaction was shown for inorganic phosphorus (Pi) concentration but not sugar concentration. Correlations for improving P and sugar composition were favorable, and with the exception of emergence there were no strong correlations with agronomic traits. The correlation of emergence with Pi was significant (r = −0.59), indicating reduced emergence due to the mutation. Reduced emergence is a problem in low phytate germplasm generally and further research is necessary to genetically improve emergence of low phytate lines.

Impact of mips1, lpa1, and lpa2 Alleles for Low Phytic Acid Content on Agronomic, Seed Quality, and Seed Composition Traits of Soybean

“…The triple‐mutant mips1/lpa1/lpa2 lines had the lowest average PA content (1939 μg g −1 ), which was significantly lower than all other genotypes except for lpa1/lpa2 . These results were not consistent with other studies, especially that lpa1 ‐only lines had a higher PA content than mips1‐ only lines (Wilcox et al, 2000; Bilyeu et al, 2008; Maupin et al, 2011). For example, in a study of six LPA soybean lines, Maupin et al (2011) found that the all three lpa1/lpa2 lines had significantly lower PA content than all three mips1 lines, with the lpa1/lpa2 lines ranging in PA content from 878 to 1269 μg g −1 , while mips1 lines ranged from 1935 to 2071 μg g −1 .…”

“…These results were not consistent with other studies, especially that lpa1 ‐only lines had a higher PA content than mips1‐ only lines (Wilcox et al, 2000; Bilyeu et al, 2008; Maupin et al, 2011). For example, in a study of six LPA soybean lines, Maupin et al (2011) found that the all three lpa1/lpa2 lines had significantly lower PA content than all three mips1 lines, with the lpa1/lpa2 lines ranging in PA content from 878 to 1269 μg g −1 , while mips1 lines ranged from 1935 to 2071 μg g −1 . The results showed the additive nature of each allele effect on PA content when combined with another allele, which had previously been reported for lpa1/lpa2 lines, but not for any combination with the mips1 allele (Wilcox et al, 2000; Bilyeu et al, 2008).…”

“…The triple‐mutant genotype, mips1/lpa1/lpa2 , had a sucrose content of 8.25%, only slightly lower than mips1‐ only lines. The sucrose contents for mips1 genotypes was in line with results reported by Maupin et al (2011), who reported sucrose contents of between 9.0 and 9.1%, but the non‐ mips1 lines in this study also had higher sucrose contents.…”

“…The triple‐mutant mips1/lpa1/lpa2 lines had the highest overall raffinose content (0.86%), significantly higher than all other mips1 mutant lines, but not significantly different from the non‐ mips1 lines. Overall, raffinose contents were higher than previously reported, and none of these genotypes have raffinose contents that would be considered “low” (Sebastian et al, 2000; Saghai‐Maroof and Buss, 2008; Maupin et al, 2011).…”

Identification of Quantitative Trait Loci for Sucrose Content in Soybean Seed

“…Variation among genotypes, locations, and genotype ´ location interaction were all significant for sucrose content in F 3:6 lines in 2011, as expected for any quantitative trait evaluations (Table 3). The results also support the observations in other studies where genotypic and environmental effects were significant for soybean seed sucrose (Cicek et al, 2006;Maupin et al, 2011). It is important to note that although the genotype by location interaction was statistically significant, it was almost negligent in comparison to the error term.…”