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A high oleic:linoleic acid ratio (O/L) in peanut (Arachis hypogaea L.) seeds is controlled primarily by two recessive genes, ahFAD2A and ahFAD2B ([ol.sub.1] and [ol.sub.2]). Marker-assisted breeding for high O/L could become routine provided that userfriendly and economical markers could be developed that would target mutant alleles underlying the trait. Previously, a mutant allele of ahFAD2A was characterized as having a 448G>A transition, and two ahFAD2B alleles were found with either a nonsense mutation caused by a single nucleotide insertion (441_442insA) (high O/L line F435) or a transposable element insertion (Flavorunner 458). A cleaved amplified polymorphic sequence (CAPS) marker targeting the 441_442insA site in ahFAD2B was designed. 'Georgia-02C' and 'Georgia Hi-O/U, derivatives of irradiation-induced high O/L mutants, showed CAPS marker and sequence data diagnostic for the genetic mutations in ahFAD2 found in the spontaneous mutant line F435. In addition, conflicting reports regarding the organization of ahFAD2 genes and ahFAD2B mutations were reexamined. Our data clearly show that molecular markers can be used to screen for known ahFAD2 mutations and that only two mutant ahFAD2B alleles are present in the U.S. high O/L cultivars. Genetic markers based on these mutations have utility for detecting seed mixtures and heterozygotes, and can accelerate introduction of the high O/L trait into peanut breeding lines. doi: 10.2135/cropsci2009.01.0021

Zero erucic acid Ethiopian mustard (Brassica carinata A. Braun) seed oil has a low oleic acid content (330 g [kg.sup.-1]). The mid oleic acid line AB3 (650 g [kg.sup.-1]) and the high oleic acid line AB1 (830 g [kg.sup.-1]) have been developed. The objective of this research was to study the inheritance of both traits in Ethiopian mustard. Plants of AB1 were reciprocally crossed with plants of the standard line 25X-1, the low linolenic acid line AB4, and AB3. Plants of AB3 were also reciprocally crossed with plants of 25X-1. A genetic study was conducted through the analysis of the fatty acid profile of [F.sub.1], [F.sub.2], [BC.sub.1][F.sub.1], and [F.sub.3] seed generations. The results revealed that mid oleic acid content in AB3 was determined by partially recessive alleles at a single locus OI, whereas high oleic acid content in AB1 was the result of partially recessive alleles at two loci, OI and OI2. Both loci produced an increment of oleic acid content of similar magnitude, although ol2 alleles had phenotypic expression only in presence of ol alleles in homozygous condition. Segregation patterns for oleic acid content were similar in crosses of AB1 with 25X-1 and AB4, which indicated that loci for high oleic acid content were not related to loci for low linolenic acid content. Recombination of genes controlling high oleic acid and low linolenic acid content resulted in phenotypes with >850 g [kg.sup.-1] oleic acid and

Soybean [Glycine max (L.) Merr.] oil with high content of oleic acid (>300 g [kg.sup.-1]) is less susceptible to oxidative changes during refining, storage, and frying. Two mutants (M23 and M11) were developed that had high content of oleic acid in the seed oil compared with the original cultivar (Bay). The objective of this study was to compare the genetic control of oleic acid content in these mutants. Reciprocal crosses were made between each mutant and Bay and between the two mutants. There were no maternal and cytoplasmic effects for oleic acid content in any of these crosses. The analysis of fatty acid composition of the parents, [F.sub.1], and [F.sub.2] seeds from the cross between M23 and Bay and between M11 and Bay indicated that oleic acid content was controlled by a single gene. The cross between M23 and M11 indicated that each mutant had a different allele at the same locus for the oleic acid content. The Ol allele for low oleic acid content in Bay was partially dominant to the allele ol for high oleic acid content in M23 but completely dominant to the allele [ol.sup.a] for high oleic acid content in M11. The allele [ol.sup.a] in M11 was completely dominant to the ol allele in the M23. There was a complete inverse relationship between oleic and linoleic acid contents in both mutants. It indicated that the mutant alleles ol and [ol.sup.a] may also control the linoleic acid content by blocking the synthesis of this acid at the step of oleic acid desaturation.

The development of hybrids with high levels of monounsaturated oleic acid is an important goal among sunflower (Helianthus annuus L.) breeders. The objective of this study was to determine the association of high oleic alleles with agronomic and chemical characters of sunflower. Two cytoplasmic male sterile and two restorer parental lines averaging 890 g kg to the -1 oleic acid and their isogenic counterparts with 230 g kg to the -1 oleic acid were crossed to obtain four high-oleic and four low-oleic acid near-isogenic hybrids. The pairs of isogenic hybrids were evaluated for agronomic performance in a replicated test at several locations differing widely in temperature and water availability during seed formation. High oleic acid hybrids produced significantly greater seed yield, oil content, and above-ground biomass than low oleic acid hybrids. For the other evaluated characters, high oleic acid hybrids were earlier and less self-compatible than their isogenic counterparts with low oleic acid forms, although there were differences between environments and genetic backgrounds. The high oleic acid hybrids averaged 626 g kg to the -1 higher oleic acid content than low oleic hybrids. This difference was lower for open-pollinated seed although high oleic hybrids maintained oleic acid levels near 775 g kg to the -1 under open pollination. The high oleic OL allele appears to have a positive influence on yield and oil content and a negative effect on self-compatibility; but it depends somewhat on the genetic background into which they are introduced.

New sunflower hybrids have been genetically revamped to produce a healthful vegetable oil that's so much better for deep fat frying that domestic and export markets may quickly grow. 'By [...]

Current breeding programs dealing with the modification of oleic and linoleic acid concentrations in sunflower (Helianthus annuus L.) require large numbers for chromatographic analyses of half seeds. The objective of this research was to study the potential of near-infrared reflectance spectroscopy (NIRS) to estimate the oleic and linoleic acid concentrations of intact single sunflower achenes. Spectra from intact achenes were collected with a specially designed adapter and a standard monochromator instrument. Calibration equations for oleic and linoleic acid were developed from a calibration set including 465 intact achenes with a large range of variation for both fatty acids and were validated with an external set of 100 intact achenes. The coefficient of determination between NIRS and gas-liquid chromatography (GLC) was 0.88 for both fatty acids in external validation, demonstrating the high reliability of NIRS to predict oleic and linoleic acid concentrations of intact, single sunflower achenes. The calibration equation for oleic acid was used to evaluate two [F.sub.2] populations segregating for this fatty acid, which were further analyzed by GLC. The use of NIRS predictions permitted the discrimination of the majority of the high oleic acid achenes ([is greater than] 700 g [kg.sup.-1]), demonstrating the use of NIRS for selecting sunflower achenes with specific oleic and linoleic acid concentrations., The availability of rapid, nondestructive methods to evaluate seed quality traits is one of the most important factors determining the success of plant breeding projects (Robbelen, 1990). In oilseed crops, [...]