Relationships between the fan Allele and Agronomic Traits in Soybean

Abstract

Normal levels of linolenic acid (70‐80 g kg‐1) in soybean [Glycine max (L.) Merr.] oil adversely affect oil flavor and stability. The mutation‐induced line C1640 has half the normal level of linolenic acid (37 g kg‐1), but is 24% lower yielding than ‘Century’, from which it was selected. This study was conducted to determine if there are genetic relationships betweena gronomictr aits and the fan allele for low linolenic acid identified in C1640. Century and ‘Harper’, both with the FanFan alleles for normal 18:3, were crossed with C1640 containing the fanfan alleles for low 18:3. Both FanFan and fanfan segregates from the two crosses were evaluated for agronomic traits and linolenic acid in replicated tests over a 2‐yr period on a Chalmers soil (fine‐silty, mixed, mesic Typic Haplaquoll) at the Purdue University Agronomy Research Center near West Lafayette, IN. The fanfan segregates in the Century × C1640 cross averaged slightly higher in seed yield and taller in plant height than the FanFans egregates. In the Harper × C1640 cross, fanfan segregates averaged 1 d later in maturity than FanFan segregates. Mean values for FanFan and fanfan segregates for other traits in both crosses were essentially the same. These data indicate that there are no associations between the fanfan alleles and those agronomic traits needed in commercial soybean cultivars with low levels of linolenic acid. Apparently the low yield of C1640 is controlled by genetic changes independent of the mutation for low 18:3. Regression of linolenic acid level on maturity dates for both FanFan and fanfan segregates in the Harper × C1640 cross show that segregates of both genotypes tended to have increased linolenic acid at later maturity dates. This could be attributed to the cooler temperatures during seed maturation to which the later maturing segregates were exposed.

Impact of low linolenic acid content on seed yield of winter oilseed rape (Brassica napus L.)

“…This means, that under usual growing conditions the lower C18:3 content in the cytoplasmic membranes of roots and leaves seems to be tolerated without yield losses. Similar results were demonstrated in mutant lines of soybean (Wilcox et al 1993) with decreased C18:3 content in seed oil and root lipids (Wang et al 1989); no association was found between C18:3 content and characters such as seed yield, maturity, lodging or plant height in F2-derived lines of the two cross combinations investigated.…”

Combinations of mutant FAD2 and FAD3 genes to produce high oleic acid and low linolenic acid soybean oil

“…Oleic acid and linolenic acid contents were demonstrated to be influenced greatly by temperature and modifier genes in several studies (Chapman et al 1976;Dornbos and Mullen 1992;Graef et al 1988;Hyten et al 2004;Wilcox et al 1993). It is shown clearly in this study that when two mutant FAD3A and FAD3C genes were incorporated into a high oleic acid background to reduce the enzymatic activity of FAD3, the linolenic acid content of HOLL soybeans was still affected by environmental factors while the oleic acid content showed a reduction in the Columbia, MO location compared to Portageville, MO that was statistically insignificant.…”

Influence of Reduced Palmitate Content on Agronomic and Seed Traits of Soybean

“…They indicated that reduction of linolenate content in soybean oil did not affect yield, maturity, and lodging. Wilcox et al (1993) determined the genetic associations of the mutant allele in C1640 that controls reduced linolenate content with agronomic traits. They reported that the allele for reduced linolenate had no genetic relationships with agronomic characters.…”