Canola, Rapeseed, and Mustard: For Biofuels and Bioproducts - Industrial Crops: Breeding for BioEnergy and Bioproducts - page 141

Increased seed yield in Brassica oilseeds through the exploitation of heterosis
has become a major breeding target globally in recent years since reports of
heterosis for seed yield in B. rapa , B. juncea , B. napus , and B. carinata have
appeared in the literature [ 43 ]. Brassica breeders are attempting to reach the yield
stability target through the development of hybrid canola/rapeseed/mustard culti-
vars [ 43 ] because hybrid cultivars are thought to contribute to yield stability since
they are usually more abiotic and biotic stress tolerant [ 70 ].
Brassica breeders have focused on early maturity in spring habit canola/rape-
seed/mustard and have focused on winter hardiness in winter habit B. napus canola
[ 1 , 46 ] to achieve their adaptation to local environments. In short-season growing
areas such as Canada or northern Europe, early maturity is required to avoid frost
damage, while in longer-season growing areas, early maturity is required to permit
annual multi-cropping [ 46 ].
Improved seed quality as a breeding target globally involves increasing oil
content and protein content while reducing fiber content [ 43 ]. Oil quality improve-
ment targets involve modifying oil profile for specific end-use markets. Reduced
erucic acid content for edible oil, biofuels, and bioproducts; increased erucic acid
content for industrial oil; and reduced linolenic acid and increased oleic acid
content for improved oil stability are common breeding targets throughout the
world [ 1 , 43 , 69 ]. High lauric acid canola was developed as a substitute for palm
oil [ 71 ]. The development of very high oleic acid canola (80-90 % oleic acid) is a
target since high oleic acid levels are required for industrial applications because
oleic acid is a chemical feedstock for further chemical synthesis [ 72 ]. The devel-
opment of super high erucic acid B. napus rapeseed with erucic acid levels over
66 % has been a breeding target for 20 years [ 1 ]. Oil profile modifications are a
target in B. juncea where several fatty acid profile modifications have been devel-
oped including reduced linolenic acid types as well as mid and high oleic types [ 73 ].
Meal quality improvement targets include increasing protein content and reduc-
ing fiber, sinapine, and phytic acid in B. napus , B. rapa , and B. juncea [ 41 ]. The
development of yellow-seeded B. napus cultivars (which would increase protein
content and reduce fiber content in the meal simultaneously) is a major seed quality
improvement target globally [ 1 ].
The development of herbicide-tolerant canola B. juncea and B. napus has been a
major breeding target in Canada and Australia since the 1980s [ 63 ]. Canada was the
first canola-/rapeseed-producing country to begin commercial production of
herbicide-tolerant canola/rapeseed/mustard [ 63 ].
Resistance to diseases and pests in canola/rapeseed/mustard is an important
breeding target globally, with different diseases and pests of importance in different
production areas of the world [ 1 , 46 ].
Abiotic stress resistance is also an important breeding target that involves
improving the frost, heat, drought, and salt tolerance of Brassica oilseeds [ 16 ].