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WELCOME
Breeding for colour development in vegetable crops : current approaches and achievements
DIVISION OF VEGETABLE SCIENCEINDIAN AGRICULTURAL RESEARCH INSTITUTE
NEW DELHI-110012
R AV I N D R A D A N G I
R O L L N O - 2 0 6 9 8
Content
Introduction
Pigments in Vegetables : Types & Distribution
Breeding Approaches for Colour Improvement
in Vegetables
Research Achievements
Edible colour rich varieties of vegetable crops
Case Studies
INTRODUCTION
Nutritionists of WHO-FAO suggested that vegetables
is essential for balance diet
Vitamin A deficiency (VAD) is recognized as a
serious public health problem in India
It is estimated that 25% of the 15 million blind
people globally are from India
Colourful fruits and vegetables have enormous
nutritional and medicinal value
PhotosynthesisEncourage pollination
Higher nutritional value Higher consumer preference
What are the significance of colours in vegetables?
Pigment class Main subgroups
Typical colors Examples
Carotenoids Carotenes, lycopene andxanthophylls
Orange, yellow,, red
Carrot, tomato, water melon,pepper, Leaf y Vegetables
Flavonoids Anthocyanins;flavonols
Purple, blue,red
Eggplant, redCabbage, onion
Betalains β-cyanins andβ-xanthins
Red,orange, yellow
Beet, SwissChard
Chlorophylls a and b Green Any green plants
Pigments in vegetable crops: Types & Distribution
(Chen,2015)
Carotenoids are lipophilic, tetraterpenoids organic pigments.
CAROTENOIDS
Carotenoids in Human NutritionSignificance of Provitamin A Carotenoids in Developing Countries
Fertility and Reproductive Success
Prevention of Oxidative Stress and Inflammation
Vision and Diseases of the Eye
Cognitive Decline and Alzheimer’s Disease
Cancer Prevention and Treatment
Metabolic Syndrome, Obesity, Cardiovascular Disease, and Diabetes
(Chen,2015)
(Cazzonelli et al., 2010)
CAROTENOIDS RICH VEGETABLES
β-carotene
α-carotene
Lycopene
Lutein + zeaxanthin
β-Cryptoxanthin
Antioxidant Properties
Cardiovascular Diseases Control
Role in Obesity
FLAVONOIDS
Water-soluble polyphenolic compounds.
Distribution of flavonoids in vegetables
Anthocyanins
Flavones
Flavonols
Isoflavones
Betalains
Betalains
β-cyanins
β-xanthin
Betalains are a class of water-soluble pigments that are found only in the order
Caryophyllales.
Betalains differ from anthocyanins in the chemical structures but share
similarities to anthocyanins in the color spectra, biological functions.
For example, betalains contain nitrogen but anthocyanins do not.
Similarly, betalains are also localized in vacuoles.
(Chen,2015)
Betalains
Swiss Chard
CactiAmaramths
Beet
Breeding for colour development in vegetables
Breeding Approaches For Colour Improvement In
Vegetable Crops
Selection
Mutagenesis
Hybridization
Interspecific hybridization
Somaclonal Variation
Genetic engineering (Singh, 2009)
Selection Most of the colour varieties are developed by this method
Selected on the basis of phenotype
Carrot cream colour variety Pusa Kulfi content high lutein and Pusa
Ashita have high anthocyanin are the two Classical example
Pusa Kulfi Pusa Ashita
MutagenesisCarotenoid pathway mutants in Pepper & Tomato
Species Mutant name Phenotype References
Tomato r (yellow flesh) Yellow fruit color Fray and Grierson,1993
delta Orange fruit color Ronen et al.,1999
tangerine Orange fruit color Isaacson et al.,2002
Beta Orange fruit color Ronen et al.,2000
Pepper y (yellow) Yellow fruit color Lefebvre et al., 1998
c2 Yellow fruit color Thorup et al., 2000
(Farré et al.,2010)
Hybridization
High-Carotene Cucumber Germplasm
Early Orange Mass 400, Early Orange Mass 402, Late Orange Mass 404
Developed by crosses between U.S. pickling cucumber lines (Cucumis
sativus L. var. sativus) and the orange-fruited Xishuangbannan cucumber
(C. sativus L. var. xishuangbannanesis Qi et Yuan)
Fig. Cross sections of four mature fruits of LOM 404 high carotene cucumber (15-25 mg.kg-1carotenes).
Simon and Navazio, 1997
Interspecific Hybridization
M. L. Tomes(1958) , bred Caro-Red, a Provitamin -A rich tomato variety
Develeped by cross between common tomatoes, Lycopersicon esculentum
Mill., and the wild species, L. hirsutum Humb
Due to its orange colour it not got commercial acceptance and consumers
preference
Tissue culture derived plants show variation termed somaclonal variation
Chromosomal rearrangements are an important source of this variation
A cultivar of sweet potato ‘Scarlet’ having higher yield and disease
resistance characteristics similar to their parent but also have darker and
more stable skin colour
Somaclonal Variation
(Moyer and Collins, 1983)
Cauliflower Or gene
Semi-dominant, single-locus mutation
No alteration in carotenoid biosynthetic genes expression
Function- regulating the differentiation of some non-photosynthetic plastids
into chromoplasts, which provide the deposition “sink” for carotenoid
accumulation
The Or gene encodes a plastid membrane protein
Beta carotene range from 3 to 320 µg/ 100 gram fresh tissue
Achievements
(Li et al.,2012)
A. Normal cauliflower
B. Orange cauliflower (heterozygous) curd
C. Orange homozygous mutant
D. Apical shoot of three month old normal cauliflower
E. Apical shoot of three month old orange cauliflower
Continued….
Cauliflower Pr gene
(Chiu et al.,2010)
Anthocyanins are responsible for purple color.
Purple (Pr) gene mutation is a spontaneous mutation.
The cauliflower purple mutation controlled by a single, semidominant
gene
Phenotype - Intense purple color in curds and a few other tissues
A commercial purple cauliflower cultivar Graffiti (Harris Seeds)
cultivated in USA.
The curds accumulated approximately 3.75 mg cyanidin diglucoside
equivalent per g fresh weight
Figure. Phenotypic comparison between wild type and the cauliflower Pr mutant. A, Young seedlings of 5-d-old plants. B, Young plants of 3-week-old. C, Curds of cauliflower plants grown in field. D, Young flower buds.E, Flowers. F, Young (inner) and old siliques of G, Seed endosperms wild type (left)and mutant (right).
Continued….
Edible colour rich varieties of vegetable crops
Carrot
Pusa Rudhira(High lycopene)
Pusa Meghali(High β-carotene)
Pusa Ashita (High anthocyanin)
Radish
Pusa Mridula (Lycopene)
Pusa Jamuni (Anthocyanin )
Pusa Gulabi(Anthocyanin
)Tomato
Pusa Rohini (Lycopene) Pusa Uphar (Lycopene)
Amaranths Pusa Lal Chaulai
(Anthocyanin) Onion Pusa Ridhi
Rich in antioxidant (quercetin 107.42 mg/100g)
Pumpkin Pusa Vikas (β-carotene) Continued….
Case Study -1
To enrich the anthocyanin content of the fruits of a cultivated tomato cultivar
To enhance the antioxidant value of tomato fruits
objectives
Materials and Methods
Two gene - delila and rosea1 from antirrhinum majus
Transformation of tomato with pGAntho construct was carried out by Agrobacterium-mediated gene transformation
Figure1 . Schematic diagram of the pGAntho gene construct in pGreen II.
Gene cloning and vector construction
Results and Discussion Transgenic tomato plants accumulating high amounts (70–100 fold) of anthocyanin in the fruit were developed
Figure1. Biochemical analysis of tomato fruit. a, Anthocyanin content; b, Antioxidant capacity.
WT, Wild type; C, Commercial; V, vector and pGAntho, Transgenic tomato.
a b
Figure 2. Biochemical analysis of tomato fruit. c, Total carotenoid content; d, Lycopene content.
WT, Wild type; C, Commercial; V, vector and pGAntho, Transgenic tomato.
c d
Continued….
Gene Expression Analysis
Figure 3. Expression analysis of Del and Ros1 and their targets:
a, Relative mRNA levels of Del and Ros1 at three developmental stages of fruit.
b, Relative mRNA levels of F3H and CHI induced by Del and Ros1 at three developmental stages of fruit.
a b
Figure . Tomato fruit colour in pGAntho (E8:Ros/Del) transgenic, WT-control and vector control .a Comparison of ripened fruits of pGAntho, WT-control and Vector control. b Transverse section of the ripened fruits of pGAntho, WT-control and Vector control.
Fig. Fruit colour during developmental stages of the fruit, from left green, breaker and red-ripe of WT-control (top) and pGAntho (bottom).
b
a
In conclusion, they have developed transgenic tomato
producing fruits rich in anthocyanins
This approach has achieved high levels of anthocyanin
content through-out the fruit
The fruit is of value for its health benefits as it is rich in
anthocyanins along with naturally occurring carotenoids.
In addition to the direct consumption, these fruits can also
be utilized to extract biological food colourants and
anthocyanin compounds used as a nutraceuticals.
INFERENCE
Case Study -2
To develop carotenoids and anthocyanin rich transgenic sweet potato with
high antioxidant capacity.
To characterize carotenoid contents and antioxidant activity in transgenic
sweet potato
Objective
Materials and MethodsPlant materials and expression vectors
Take anthocyanin rich sweet potato cultivar Sinzami (SZM) as wild type (WT). Under the control of the cauliflower mosaic virus (CaMV) 35S promoter was constructed. Agrobacterium -mediated transformation
Fig.Schematic diagram of the T-DNA region of the IbOr constructs used for plant transformation. LB and RB, left and right T-DNA borders, respectively; 35S Pro, CaMV 35S promoter; gray boxes, cloning site of gateway vector systems; FLAG, FLAG octapeptide.
Fig. Phenotypes of storage roots and leaves of three IbOr transgenic and wild-type (WT) lines.
Fig. Expression of IbOr in leaves and storage roots
Results and Discussion
Carotenoids contents in the storage roots of transgenic and wild-type sweet potato plants (μg /g DW).
Fig. Analysis of total anthocyanin contents.
Continued….
Photograph of aerial plant parts and storage roots
Fig. Average yields of storage roots
INFERENCE
In conclusion, anthocyanin-rich transgenic sweet potato plants with high
carotenoids were successfully generated
Carotenoids contents, and antioxidant activity in storage roots were
characterized
Transgenic plants is expected to contribute to human health by increasing
the contents of carotenoids
Transgenic sweet potato show tolerance to environmental stresses .This
would be beneficial for sustainable agriculture on marginal lands
worldwide.