References

Taylor, et al. 1992. Inhibitors of amino acid biosynthesis strategies for imparting glysphosate tolerance to crop plants. In Biosynthesis and Molecular Regulation of Amino Acids in Plants. B.K. Singh, H.E. Flores, and J.C. Shannon, Eds. American Society of Plant Physiologists, Rockville, MD, pp. 139-145. Beversdorf, W.D., J. Weiss-Lermann, L.R. Erikson, and V. Souza Machado. 1980. Transfer of cyto-plasmically-inherited triazine resistance from birds rape to cultivated...

Specialty Oil Profile Double Low Rapeseed Canola Cultivar Development

Double-low rapeseed (canola) contains over 10 linolenic acid in the seed oil (Ratanayake and Daun 2004). Linolenic acid contains three double bonds, which reduces the oil stability and shelf life of double-low rapeseed (canola) oil. A new breeding objective of modifying the fatty acid profile of double-low rapeseed (canola) oil to increase the stability of the oil emerged in the 1980s. The initial focus was on reduction of the linolenic acid concentration in the oil. The world's first...

Contents

SECTION 1 Improvement of Agronomic and Microbial Traits Chapter 1 Molecular Strategies for Increasing Seed Oil Content 3 Randall J. Weselake, David C. Taylor, Saleh Shah, Andr Laroche, and John L. Harwood Chapter 2 Engineering Industrial Oil Biosynthesis Cloning and Characterization of Kennedy Pathway Acyltransferases from Novel Oilseed Chapter 3 Accumulation of Epoxy Fatty Acids in Plant Oils 33 David Hildebrand, Runzhi Li, Keshun Yu, and Tomoko Hatanaka Chapter 4 High-Erucic Acid,...

The Lands Cycle Enzymes and Other Acyltransferases

Much of our focus, and that of other groups, has been dedicated to studying the Kennedy pathway acyltransferases. However, any enzyme that could affect the flux of fatty acids between the acyl-CoA, phospholipid, and neutral lipid pools must be considered for a potential role in directing the flow of novel fatty acids into TAG. Most types of unusual fatty acids (including oxidized or otherwise damaged acyl groups, which occur naturally in all organisms) must be rapidly removed from their site of...

Double Low Low Erucic Acid and Low Glucosinolate Rapeseed Canola Cultivar Development

The development of low-erucic acid rapeseed cultivars for edible oil purposes created a high-quality vegetable oil from low-quality rapeseed oil. However, the nutritional value of rapeseed meal was limited by plant secondary metabolites known as glucosinolates commonly found in Brassica species (Kimber and McGregor 1995). Glucosinolates affected the thyroid gland of animals fed rapeseed meal, and the glu-cosinolates reduced the palatability of rapeseed meal. Rapeseed breeders screened rapeseed...

G3pdh

FIGURE 1.2 Carbohydrate catabolism in relation to lipid biosynthesis in photosynthetic developing seeds of B. napus L. Reactions having a substantial effect on the flow of carbon into seed oil are indicated with an asterisk. Glycolysis operates in the cytosol and plastid. Cytosolic triose phosphate (TP) in the form of dihydroxyacetone phosphate provides substrate for cytosolic sn-glycerol-3-phosphate dehydrogenase (G3PDH) to produce the glycerol backbone for triacylglycerol (TAG) bioassembly in...

High Erucic Acid Low Glucosinolate Rapeseed Cultivar Development

High-erucic acid, low-glucosinolate B. napus cultivar development began at the University of Manitoba in the early 1970s as a parallel and complementary breeding program to the double-low rapeseed canola breeding program Scarth et al. 1992 . Generic breeding objectives were still to develop locally adapted rapeseed cultivars with improved productivity and seed quality. Selection for earlier maturity, reduced plant height, increased oil content, reduced glucosinolate concentration, and increased...

Herbicide Tolerant High Erucic Acid Rapeseed Cultivar Development

Competition from weeds is a major production concern for double-low rapeseed canola rapeseed growers in western Canada Kimber and McGregor 1995, Orson 1995 . To address this concern, Brassica breeders have developed double-low canola and rapeseed cultivars with novel, broad-spectrum herbicide tolerance. Five different types of novel herbicide-tolerant canola cultivars have been developed and released in Canada starting in the 1970s McVetty and Zelmer 2007 . Double-low rapeseed B. napus...

Expression of Plastidial or Bacterial GPAT

Jain et al. 2000 investigated the GPAT-catalyzed reaction as a target for enhancing seed oil content. The investigators expressed a cDNA encoding a plastidial saf-flower GPAT or the gene encoding Escherichia coli GPAT during seed development in Arabidopsis under greenhouse conditions. The construct for plastidial safflower GPAT was designed to remove the plastidial targeting sequence. Analyses of T2 seeds revealed average oil content increases, on a relative basis, of 22 and 15 for expression...

Overexpression of DGAT

Bouvier-Nave et al. 2000 demonstrated that transformation of tobacco with cDNA encoding type 1 Arabidopsis DGAT1 AtDGAT1 , using a constitutive promoter, resulted in as much as a seven-fold increase in the TAG content of leaves compared to the wild-type plant. Jako et al. 2001 further showed that seed-specific expression of AtDGAT1 in Arabidopsis using a napin promoter resulted in 11 to 28 relative increases in seed oil content in homozygous napin AtDGAT1 lines. All transgenic lines with...