Seed Source Affects Field Emergence of Low‐Phytate Soybean Lines

Abstract

Seed production in subtropical environments is commonly used by soybean [Glycine max (L.) Merr.] breeders to reduce the number of years for cultivar development. Low‐phytate (LP) soybean lines with the mips allele had substantially reduced field emergence when planted with seed from a subtropical source. The objective of this study was to determine if seed source also would impact the field emergence of low‐phytate lines with the pha1 and pha2 alleles. Seed of six BC3F4‐derived LP lines, the LP donor parent CX1834‐1‐6 (CX1834), and the normal‐phytate (NP) recurrent parent B01769B019 (B019), was harvested from the field at Ames, IA, in 2005 (IA‐2005), at Ponce, PR, in January 2007 (PR‐Jan), and at Ponce, PR, in May 2007 (PR‐May). The three seed sources of the eight lines were evaluated at three Iowa locations in 2007. The mean field emergence of LP lines was 77.6% for the IA‐2005 source, 70.1% for the PR‐Jan source, and 25.4% for the PR‐May source while that of B019 ranged from 80.3 to 82.0% for the three sources. The seed source used to plant lines with the pha1 and pha2 alleles can have a significant influence on their field emergence, which can impact the development and evaluation of LP lines and on seed increases for commercial production.

Genetic Improvement of Seedling Emergence of Low‐Phytate Soybean Lines

“…They found that the emergence of some of their LP backcross lines was significantly better than CX1834 and equal to the NP parent when grown from seed harvested in Puerto Rico during January 2005. Anderson and Fehr (2008) found similar results when the lines and parents were tested with seed harvested in Ames, IA, in 2007. However, the emergence of the same LP backcross lines was significantly less than the NP parent when grown from seed they harvested in Puerto Rico during May 2007, which indicated that the emergence of LP lines with the pha1 and pha2 alleles was influenced by the source of the seed used for planting.…”

“…The study indicated that the LP trait remained relatively constant across different external P levels. Anderson and Fehr (2008) evaluated the impact of seed source on the emergence of six of the BC 3 F 4 -derived lines found by Spear and Fehr (2007) to have improved seedling emergence compared with CX1834. Three seed production environments were evaluated; Ames 2005, a Puerto Rico January harvest, and a Puerto Rico May harvest.…”

“…The history of line development of the LP lines with low linolenate was described by Anderson (2007). The plots were two-rows (2007) were not useful because the emergence of all the LP lines and checks was too low due to the seed source effect reported by Anderson and Fehr (2008). Seed of all the entries was harvested from the three locations for subsequent testing in my study.…”

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

“…However, the reasons causing low field emergence in LPA soybeans is still under study, as emergence is a very complex trait. Of the possibilities noted in previous research, reduced germination, weakened seedling vigor, accelerated seed aging, and seed source environment have all been implicated in this issue (Oltmans et al, 2005; Anderson and Fehr, 2008; Maupin and Rainey, 2011). Of these, seed source environment has by far been the most consistently observed.…”

Seed Inorganic Phosphorus Stability and Agronomic Performance of Two Low‐Phytate Soybean Lines Evaluated across Six Southeastern US Environments

“…In past studies, reducing the phytic acid has not inhibited agronomic performance (Shi et al, 2007; Spear and Fehr 2007; Bilyeu et al, 2008; Gillman et al, 2009; Scaboo et al, 2009). However, reduced seedling emergence remains a concern, because other LP germplasm developed from donor line CX1834 have suffered from subpar field emergence (Oltmans et al, 2004; Anderson and Fehr, 2008; Maupin et al, 2011).…”