1. CROP IMPROVEMENT IN MANDARIN (Citrus reticulata Swingle)
ASPEE COLLEGE OF HORTICULTURE AND FORESTRY
DEPARTMENT OF FRUIT SCIENCE
CROP IMPROVEMENT IN MANDARIN (Citrus reticulata Swingle)
VIKAS RAMTEKE
PH.D. 1ST SEM
DEPARTMENT OF FRUIT SCIENCE
DR. T.R. AHLAWAT
ASSOCIATE PROF.
DEPARTMENT OF FRUIT SCIENCE

2. Geographical Distribution
Origin
The center of origin and diversity of citrus is generally considered to be south east asia epecially East India, North Burma and South west Chinna.
Chromosome number 2n=18
Geographical Distribution
Citrus is commercially grown in the tropical and subtropical regions around the world, primarily between the latitudes of 40⁰N to 40⁰S from equator.
Hot humid, warm subtropical and even cooler sub temperate.

3. PRODUCTION (million MT)
World and National scenario of citrus
Cultivar- wise citrus cultivation (%) in India
AREA
(million HA)
PRODUCTION (million MT)
PRODUCTIVITY(MT)
1.0
10.7
11.2
8.6%
NHB, 2014

4. Taxonomy Order : Geraniales Sub- Order : Geraniinea Family : Rutaceae
Sub family : Aurontoidae
Tribe : Citrae

5. Citrus Classification
Swingle : 16 species
Tanka :162 species
Bhattacharya and Dutta (1956) : 78 species in India
Hogson reported 159 species and classified citrae into Citrus, Poncirus and Fortunella.

6. Classification of mandarins
C. reticulata : Coorg mandarin, NagpurSantra and Kodai orange
C. unshiu : Japanese Satsuma mandarin
C.deliciosa : Willow leaf mandarin
C. nobilis : King mandarin
Kinnow mandarin : King x willow leaf
Citrus tangerina : Tangerine orange var Dancy (trifoliate x mandarins)

7. Breeding Objectives
To breed varieites suitable for agro-ecological situations.
To breed varieites having high yield potential.
To breed varieites having bigger size and round shape.
Quality (TSS/acid ratio), juice content, flavour and colour.
To breed varieites which are seedless.
To breed varieites having high juice content
To develop varieites easy to peel.

8. Cont. Exterior appearance
Adaptation to adverse climatic and soil conditions
Adaptation to mechanical harvest
Disease resistance (Phytopthora, Tristeza etc.)
Pest reistance (Nematodes, Pyslla, Lemon butterfly etc.)
Good processing quality
Longer storage life

9. Problems in Citrus Breeding
1. Incompatibility
Satsuma mandarins are pollen sterile.
Hybrids are also self incompatible.
2. Nucellar Embryony
When cross has been made the breeder will get both nucellar and zygotic embryos.
Nagpur mandarin produces only zygotic seedlings.
3. Juvenility

10. Floral biology
In subtropical climate mandarin bloom only one annual period i.e. March to April.
The flower bud induction initaiated in November and may continue upto early january.
Full bloom stage appers in spring.
In tropical areas, the tree may flower several times a year.
The main flowering season of citrus in north India (Feb- April), South India (Dec- April) and in central India (March- April and September).
Flowers are staminate and hermaphrodite borne singly or in small groups in the leaf axils on the young twigs.

12. Cont. Inflorescense in citrus species is of cymose type.
Flowers have a five petals that are white and some kinds have purple staining the outer surfaces.
The calyx is cup-like with five sepals and corolla have a five white petals alternating with sepals.
Opening of flowers start during morning and continued till evening , maximum anthesis from a. m to noon.
Stigma receptivity starts 2-3 days earlier to anthesis and lost 4 days after anthesis with maximum receptivity on the day of anthesis.
Relatively large stigma is receptive one to few days before anthesis and in some cases up to six to eight days after anthesis .

13. Inheritance Pattern Small size fruit : Dominant
Sadiness and Paleness of fruit : Dominant
Presence of thornes : Dominant Character
Presence of pubescence and oil gands in juice sac and leaf : Dominant Character
Nucellar embryony : one or two dominant genes
Frutose and aromatic compounds – Dominant (Bassene et al, 2009).
Scaleness of flower: Recessive
Resistant to Citrus Tristeza Virus: dominant allele at single locus (Ctr).

14. Character
Inheritance
References
Leaf character
Two principal genes
Soost and Cameron,1975
Anthocyanin pigment in fruit
More than one recessive genes are involved.
Spigel-Roy,1988
Tristeza virus
Single allele
Mestre et al.,1997
Texture
Polygenic control
Yamamoto et al.,1990
Polyembryony
More than one single gene
Maheshwari and Rangaswamy, 1958
Seedless character
A recessive gene
Spigel-Roy,1982
Nucellar Embryony
One or two dominant gene

15. Breeding methods
and Achievements

16. Introduction
Nagpur mandarin: It was introduced into the Central Provinces (now Maharashtra) by Ranghojee Bhonsal II in eighteenth century.
Tangerines, St.Michael Blood Orange and Large White Orange were imported and cultivated at Goojranwallah in Punjab during 1880.
Kinnow : The introduction of ‘Kinnow’ mandarin (King x Willow leaf) in 1947 showed great promise in North India. It was introduced in South India in 1958 and Punjab in 1959 and has performed extremely well in Punjab.
Cleopatra mandarin : Intoduced as a rootstock.

17. NAGPUR MANDARIN
KINNOW MANDARIN

18. Dancy : Most popular American variety also known as tangerine.
Tangor : Introduction from USA (Temple mandarin).
Satsuma : Introdcution from Japan.
Murcott : Indroduction form USA (mandarin X sweet orange).
Clementine: Native of Algeria, Monoembryonic in nature.
Beaury: It is a popular cultivar of Australia.
Emperor: Early mid season cultivar introduced from Australia.

19. Selections The most important commercial variety in south India
Coorg
The most important commercial variety in south India
it is particularly grown on a large scale in Coorg and Wynad tracts. 
Fruits medium to large, bright orange in color, oblate to globose in shape, base necked or depressed, rind thin to medium thick, easily peeled.
matures during February- March.
Khasi
Khasi is a commercially grown variety of mandarin in Assam, Meghalaya and north eastern states. 
It is locally known as Sikkim or Kamala mandarin. 
 Fruits depressed, globose to ovate, orange- yellow to bright orange, surface smooth, base even.

20. The trees are vigorous, spineless with compact foliage.
Nagpur :
The trees are vigorous, spineless with compact foliage.
Fruits medium sized, sub globose, cadmium colored, surface smooth, base slightly drawn out with glandular furrows; rind thin, loosely adherent.
  It matures during January- February.
Desi :
It is mainly grown in Punjab and adjoining hills of Himachal Pradesh.
Fruits orange colour uniform, golden yellow, rind medium thick some what thicker than coorg mandarin.

21. Clonal selections Dr.PDKV Akola
Nagpur seedless : It is a seedless clonal selection of Nagpur mandarin.
Central Citrus Research Institute, Nagpur
N4 : fruit with less seed (2.82 seed per fruit), quality of N4 was at par with Nagpur mandarin having good fruit quality (0. 82 % acidity). 
N28 : Bigger size very attractive fruits, High yielder (786 fruits/plant), medium large, upright tree; deep orange colour fruit, sweet, good flavour and juicy , fruit weight - 152g.

22. N34 : Good looking attractive fruit, 806 fruits per plant, spresding plant habit, orange colour fruits, sweet juicy, fragrant fruit peel easily.
N38 (NC-5) : Orange colour fruit, yield 765 fruits per plant, easy to peel sweet juicy fruit, fruit weight -139g.
N43 (JK-1) : Round fruit with orange colour, yield 738 fruits per plant, juicy, spreading plant habit, good aroma, seeded fruit, fruit weight -143g.
 N51 (JK-11) : Very attractive orange colour fruit, yield 805 fruits per plant, juicy, easy to peel, fruits segments easily, excellent flavour, fruit weight -136g.

23. Hybridization
Kinnow : It is cross between king x willow leaf by H.B. Frost in Popular in North India.
Encore : It is a cross of King and Willow leaf by H.B. Frost, alternate bearing.
Wilking : It is cross between king x willow leaf.
Page : Hybrid of minneala tangelo x clementine

24. Mutation Mudkhed Seedless : Bud mutant of Nagpur seedless.
Pongan 86-1: Natural bud mutant of Pongan.

25. Thank you