Agriculture Reference
In-Depth Information
allergy. High O/L ratio increases shelf life of peanut products and, therefore, their
marketability. Germplasmand advanced breeding lines with oil content as high as
55
60% and O/L ratio ranging from 7:1 to 40:1 are available for use in peanut
breeding. Globalwarminghas a signi
-
cant impact on thenutritional qualityof food
crops. Identi
cation of germplasm with stable seed quality traits will be a pre-
requisite to initiate quality breeding in peanut. Peanut cultivars with high oleate
content, developed by conventional breeding and selection, are widely grown in
the United States. Marker-aided backcross breeding has led to the development of
'
peanut cultivar in the United States. Enough genetic variation
in seed iron and zinc content has been noted, but targeted breeding for these
micronutrients in peanut is yet to begin. Peanut is devoid of
Tifguard High O/L
'
a
precursor of vitaminA. Using a cotyledon-based
Agrobacterium
-mediated genetic
transformation system and the maize
psyI
gene driven by the
At oleosin
promoter,
β
β
-carotene
—
-carotene-rich transgenic peanuts have been achieved. Transgenic peanuts with
the antifungal gene
cpo-p
inhibited
A.
avus
hyphal growthor those containing the
Rchit
gene have shown a broader spectrum of resistance against fungal infection
including
A.
avus
. Knocking out genes for the allergenic proteins, using targeting-
induced local lesions in genomes (TILLING) or RNAi approaches, has shown
promise to derive mutants or transgenic events lacking allergenic seed proteins,
with no adverse effect on seed quality or viability. These genetic stocks when
available to researchersmay lead to breeding agronomically superior nutritionally
enhanced peanut cultivars, which will be free from allergens and toxins.
KEYWORDS:
atoxin; allergy; genetic map; germplasm; groundnut; marker-
aided backcross breeding; nutrition; quantitative trait loci; transgene
a
ABBREVIATIONS
I. INTRODUCTION
II. GENETIC VARIABILITY FOR NUTRITIONAL TRAITS
A. Oil and Oil Quality
1. Oil Content
2. Oil Quality
B. Tocopherol
C. Iron and Zinc
D. Bioactive Compounds
III. PEANUT ALLERGENS
IV. PREDICTING SEED QUALITY AND ALLERGENS
A. Oil and Oil Quality
B. Mineral
C.
-Carotene
D. Allergen
V. GENETIC AND MOLECULAR BASES OF HIGH OLEATE TRAIT
VI. SEQUENCING THE PEANUT GENOME AND IMPLICATIONS IN BREEDING
VII. TRANSGENE(S) TO PRODUCE NUTRIENT-DENSE AND TOXIN- AND ALLERGEN-
FREE PEANUTS
A.
β
β
-Carotene
B. A
atoxin
