Agriculture Reference
In-Depth Information
simultaneously and shorten the time needed to introgress new trait into
improved breeding lines with the use of markers and off-season nursery,
as recently evidenced in the conversion of normal oleate Tifguard, a
nematode-resistant cultivar, to a high oleate Tifguard (Chu et al. 2011).
Taken together, it is expected that with the deployment of these resources
in the breeder
s toolbox, peanut breeders andmolecular biologists will be
able to enhance peanut yield, optimize host plant resistance to pathogens
and insects, enhance adaptation to abiotic stresses, and improve seed
quality traits (
http://www.peanutbioscience.com
).
'
VII. TRANSGENE(S) TO PRODUCE NUTRIENT-DENSE AND TOXIN-
AND ALLERGEN-FREE PEANUTS
A.
β
-Carotene
Carotenoids are an important source of vitamin A. The consumption of
carotenoid-rich food is associated with reduced risks of developing
cancer and cardiovascular disease, enhanced immune response,
improved vision, and prevention of night blindness as well the mainte-
nance of healthy skin and gastrointestinal or respiratory systems (Menkir
et al. 2008 and references therein). Carotenoids are fat soluble and
β
ciently converted to vitamin A. Carotene-rich
food, when ingested with minimal fat, has been reported to enhance
serum carotenoids and the total-body vitamin A and also to restore low
liver vitamin A concentrations to normal concentrations among Filipino
children (Ribaya-Mercado et al. 2007). Carotenoid biosynthesis path-
ways have been successfully modi
-carotene is most ef
ed by genetic engineering to enhance
the nutritional pro
les of staple food crops (Fujisawa et al. 2009;
Dwivedi et al. 2012 and references therein). A recent study involving
genetically modi
ed (GM) forti
ed
“
golden mustard
”
(
Brassica juncea
),
as a source of high
-carotene, has further shown to be cost-effective
for reducing vitamin A de
β
ciency in India (Chow et al. 2010). High
β
-carotene peanut seed or oil is expected to be effective for delivering
this essential vitamin to millions of people in the developing world
with signi
cant local peanut production and domestic consumption.
Peanut seed contains
50% oil, with most of its oil used in
domestic cooking in the developing world. Thus, it is a good candidate
for transforming it into a
45
-
∼
-carotene-rich crop, as evidenced in
Brassica
napus
, with 19- to 30-fold increase in carotenoids (predominantly
β
β
-carotene) compared with untransformed plants (Fujisawa et al.
2009). Advances in genetic engineering led to the development of a
