Genetic resources of citrus in India

1. Presented by
Buddhisatya Dowarah
Department of Horticulture and Postharvest
Technology
Institute of Agriculture, PSB
Genetic resources of citrus in India

2. Content
 Introduction
 History, origin and spread
 Botanical classification
 Cultivars found in India
 Exploration and collection
 Conclusion
 References

3. Genetic resources of citrus in India
Buddhisatya Dowarah
Department of Horticulture and Postharvest Technology
Institute of Agriculture, Visva- Bharati
Sriniketan- 731236, WB
Email ID- buddhisatyado@gmail.com
ABSTRACT
Citrus fruits are members of the Rutaceae family which contains more
than thousand species found in the tropical regions of South East of
Asia, Africa, Australia. Swingle’s and Tanaka’s attempt to classify
citrus evolved a key for identification of different citrus fruits. A large
number of citrus species/progenitors of commercial citrus fruits are
believed to have originated in India. Availability and wide gene pool in
the form of genetic diversity is a prerequisite for crop improvement .
The diversity within a species needs to be preserved for improvement
programme. The number of citrus accessions worldwide are listed to
be 6000 and in India 1495 inclusive of wild species, rootstock old
cultivars, advanced cultivars, and breeding lines are found. Thus
current efforts are need for collection of gene pool with distinct
desirable traits, which can be utilized for improvement
Keywords : Rutaceae, Genetic diversity, Accession, Improvement

4. INTRODUCTION
 Citrus have a prominent place among tropical and
sub-tropical fruits
 Wholesome nature, multifold nutritional and
medicinal values made them important
 Greater adaptability to different climatic condition
 Citrus is third most important fruit crop in India
 Citrus genetic resources spanning across 5
major groups, Acids, Oranges, Mandarins,
Pummelo-grapefruit, Wild and semi- wild species
and other related genera.
 Genetic diversity of citrus is conc in Northeastern
and Northwestern part of India. Genetic resources
in NE indicated 23 spp,1 subspecies and 68
varieties, thus act as treasure house of citrus
germplasm

5. History,Origin and Spread

6. Continue……….
 Hooker( 1872) consider not less than 78 spp of
family as natives of India.
 Bhattacharya and Dutta (1956) suggested at least
two species of subgenus Eucitrus- Citrus indica
and Citrus assamensis and three species of
subgenus Pepeda- Citrus ichangensis, Citrus
latipes and Citrus macreptera indigenous to
Assam.
 Swingle (1944) considered southern Arabia as
center of origin.
 Von Frimmel (1981) considered Mesopotamia as
the place of origin, because the seeds of citron, C.
medica found in the ruins of Nippur.
 In India citron found under wild condition in
Nilgiris, Assam and lower Himalayas.

7. Continue……
 Sweet orange believed to originated in Southern
China, from there it introduced to India during
thirteenth century.
 Mandarins have their origin in China. Their spread
over the country have taken place since the time
of Baber.
 Lemon said to be indigenous to India, however
Bonavia (1888) concludes Malaya to be home of
lemon.
 Rumphius believes the malayan word “lemeus” is
the origin of english word and that species
probably originated from Malaya.
 Bonavia and Tanaka believe that lime originated in
the Malayan regions pointing the possibility of
both English word ‘ lime’and the Indian ‘nimbu’or
‘limgbu’ having origin from Malayan word

8. Continue……..
 De Condolle thought that pummelo originated in
the island of Malaya Archipelago, however Tanaka
and Dutta claimed that pummelo was collected
wild in Garohills by Brandis, consider that from
this native area it moved east into Yongtze citrus
regions.
 The grapefruit have never found in old world. It
owes its origin as seedling or bud mutant from
pummelo, in West Indies.
 Introduction of citrus fruits to America was in the
later part of the fifteenth century by Columbus
and Spaniards while Captain Hunter introduced
orange seeds in Australia in the later part of the
eighteenth century. By the close of the15th
century Citrus species had reached almost all the
tropical and subtropical regions of Eastern

10. Bontany
 The basic botanical classification of citrus fruits
right from the natural order to genus is as follows:
Order : Geraniales (21 families)
Sub- order : Garaniinea (12 families)
Family : Rutaceae ( 7 sub-
families)
Sub-family : Aurantoidae( 2 tribes )
Tribe : Citrae ( 3 sub tribes )
Sub-tribe : Citrinae ( 3 groups, 13
genera)
Group C : Citrus fruit trees ( 6 genera)
Genus : Poncirus ( 1 species)
Fortunella (4 species)
Citrus ( 2 sub Genera)
(a) Eucitrus (b) Papeda
Generally three related genera Poncirus, Fortunella

11. Poncirus
Native home of trifoliate orange is Central and Northern
China.
Small spiny trees or shrubs with deciduous trifoliate leaves,
flower buds produced in summer, protected by bud scales,
flowers nearly sessile borne on previous seasons’ s growth
, finely pubescent fruit, and an abundant acrid oil mixed with
the acid juice in the pulp vesicles, seed many,

12. Fortunella
 latab
Kumquats are native to South- eastern China. Small, evergreen tree or
shrubs, leaves unifoliate, blunt, thick, dark-green above and paler
beneath, thickly dotted with glands on the lower side, petioles narrowly
winged, articulated or not with lamina, flowers white, smaller solitary or in
bunches in leaf axils , fruit small, oblong or globose, rind thick, sweet and
edible, small seeds, polyembryonic. Swingle separated kumquats and

13. Citrus
(i) Swingle (1948) has classified the genus Citrus as
follows;
Genus Citrus : ( 2 sub genera, 16 species, 8
botanical varieties)
Subgenus 1. Eucitrus (10 species)
Species 1. C. medica (citron)
2. C. limon (Lemon)
3. C. aurantifolia (lime)
4. C. aurantium (Sour orange)
5. C. sinensis (Sweet orange)
6. C. reticulata (Mandarin)
7. C. grandis (Pummelo)
8. C. paradisi (Grapefruit)
9. C. indica (Indian wild orange)
10. C.tachibana (Tachibana orange)

14. Continue……..
Subgenus 2. Papeda (6)
Species : 1. C. inhangensis
2. C. latipes
3. C. micrantha
4. C. celebica
5. C. macroptera
6. C. hystrix
(ii) Tanaka (1937) has recognized more than 144
species of citrus. He grouped the genus Citrus
into two subgenera viz., Archicitrus and
Matacitrus. His classification is as follows:
Genus Citrus (2 subgenera, 244 species)

15. Continue…..
Subgenera 1. Archicitrus (5 sections, 98
species)
Section 1. Papeda (12 species)
2. Limonellus (16 species)
3. Citrophorum (21 species)
4. Aruntium (28 species)
5. Cephalocitrus (21 species)
Subgenera 2. Meta citrus ( 3 Sections, 46
species)
Section 1. Osmocitrus ( 9 species)
2. Acrumen (36 Species)
3. Pseudofortunella (1 species)

16. Continue……
Hodgson (1961) made a study of both Swingle’s and Tanaka’s
treatments, he observed it to be too critical. Therefore made
a simple classification of citrus fruits (admittedly
incomplete) by grouping the different citrus fruits under four
different groups-
A. The Acid members (6 species)
1. C. medica (Citron)
2. C. limon (Lemon)
3. C. aurantifolia (Lime)
4. C. jambhiri (Rough lemon)
5. C. limettioides (Sweet lime)
6. C. limetta (Lemon x Lime)
B. The Oranges (2 species)
1. C. aurantium (sour orange)
2. C. sinensis (Sweet orange)
C. The Mandarins (3 Species)
1. C. reticulata (Mandarin orange)
2. C. unshiu (Satsuma mandarin)
3. C. nobilis (C. reticulata x C. sinensis)

17. Continue……
D. Pummelos (2 species)
1. C. paradisi (grapefruit)
2. C. maxima ( Shaddock or Pummelo)
Others of doubtful classification
1. Citrus limonia Osbeck- Rangpur lime. Conton
lemon, cravo lemon, mandarin lemon (C.
reticulata Var austera or aurantifolia x reticulata)
2. Citrus bargamia Risso- Bergemot, (C.
aurantium Var bergamia, C. Limon x C.
aurantium hybrid)
3. Citrus myrtifolia Raff- Chinnoto of Italy (C.
aurantium Var myritifolia)
4. Citrus madurensis Loureire or Citrus mitis
Blanco- Calamondin (C. reticulata Var austera x
Fortunella sp)

18. Important Citrus fruits
ACID GROUP
1. Citrus medica
2. Citrus lemon Burm( lemon)
3. Citrus aurantifolia Swingle (Acid Lime)
4. Citrus latifolia Tanaka (Tahiti or Persian lime)
5. Citrus limettioides Tanaka (Sweet lime)
6. Citrus jambhiri Lush ( Rough lemon; jambiri)
7. Citrus limetta Risso (limetta of the
mediterranean)
8. Citrus karna Raff ( Kharna Khatta)
9. Citrus limonia Osbeck ( Rangpur lime)
10. Citrus pennivesiculata Tanaka (Gajanimma)

19. MANDARIN GROUP
1. Citrus aurantium Linn ( Sour, Bigarade or Soville orange)
2. Citrus sinensis Osbeck ( Sweet orange)
3. Citrus myrtifolia Raffinesque ( Myrtle leaf orange,
Chinnoto (Italy), Chinois (France).
4. Citrus bergemia Risso ( Bargmot orange)
5. Citrus natsudaidai Hayata ( Japanese summer grapefruit)
PUMMELO-GRAPEFRUIT GROUP
1. Citrus grandis Osbeck (Pummelo or Shaddock; Chakotra)
2. Citrus paradisi Macf (Grapefruit)
MANDARIN GROUP
1. Citrus reticulata Blance ( loose skinned orange or Santra
of India)
2. Citrus unshiu M (Satsuma mandarin)
3. Citrus deliciosa Tenore ( Mediterranean mandarin; Willow-
Leaf mandarin)
4. Citrus nobilis Loureio ( King mandarin)
5. Citrus reshni Tanaka ( Spice mandarin)
6. Citrus medurensis Lou ( Calamondin)

21. Citrus Cultivars found in India

25. Mandarin group
Fairchild Kinnow
Nagpur Mandarin
Afourer
Willow Leaf Mandarin
King Mandarin

26. Wilking Mandarin Khasi Mandarin

27. Orange Group
Valencia late
Rhode Red Valencia Pineapple Jaffa Orange
Satgudi Hamlin

28. Malta Mosambi
Chinotto (sour
orange)

29. Acid Group
Pant Lemon 1
Galgal
Sharbati Lime
Eureka Lemon
Villa franca lemon
CRC3173004

30. Assam lemon Rangpur lime
Seville lemon
Kusaie lime
Acid lime

31. Grapefruit group
; gr
Frost marsh Duncan
Hudson Foster
RubyRed
Redblush

32. Pummelo group
Honey Pummelo Red flesh
Pummelo
Honey white Pummelo China White flesh
Pummelo

37. Exploration and Collection
 In India collection and conservation
of citrus species/types started in the
middle of nineteenth century it
received major emphasis. In early
part, collection and conservation
were primarily made for the quality
fruits, while current research efforts
are for collection of gene pool with
distinct desirable traits, which can be
utilized for improvement of cultivars.

38.  NRCC lead total 12 exploration mission under
NATP(PB) and IPGRI/ADB project. A total of 384
Citrus collections were collected from different
locations representing as many as 14 states viz .,
Rajasthan, Punjab, H.P., Uttar Pradesh,
Uttaranchal, Gujarat, Madhya Pradesh, Andhra
Pradesh, Maharashtra, West Bengal, Meghalaya,
Assam, Arunachal Pradesh and Sikkim (Singh and
Singh, 2003). These collected materials were
added to the pool of National gene bank. The
germplasm of rootstocks and other wild and semi-
wild nature were collected as seeds and currently
being maintained in the field repository. The
germplasm of scion cultivars were collected as
budwood and being maintained under

40. Exploration and collection of citrus
genetic diversity in North West India
 Citrus genetic diversity in northwest part of India
comprising states like Rajasthan, H.P., U.P, Punjab
and Uttaranchal are by and large maintained in home
garden by farmers, except commercial cultivars
namely Kinnow mandarin and sweet orange.
 Local citrus species which were found in NW India
includes ,lemon locally known as galgal ( C.
pseudolimon ) and Attanni, Chawanni ( C. regulosa ),
local mandarin (Butwal) cultivation,wild relatives of
citrus spp known as Glycomis pentophylla were
reported. Two new types of citrus (probable hybrids)
from Nanital area of Uttaranchal were brought to
notice ,seems to be a cross between Malta and
Pummelo. One potentially endangered citrus species
(Athanni) was sighted .Total 172 accession were
collected through the NRCC survey

41.  d
PUMMELO
GALGAL
KINNOW MANDARIN MALTA

42. Exploration and collection of citrus genetic diversity in
West India
In west India not much citrus diversity reported except
in acid lime. Exploration tour were conducted by NRCC
under NATP (PB) project and total of 13 collections
were made from the location.
ACID LIME

43. Exploration and collection of citrus genetic
diversity in NEH Region
Systemetic exploration and collection
programme started during 1950 (s) and total 56
accessions were collected and planted at
Burnihat (Assam) by Bhattacharya and Dutta
(1956) from NEH Region. In 1980-1995, ICAR
Research complex for NEH region, Barapani
Meghalaya collected 92 citrus accessions mostly
from NEH region and planted in field gene bank.
Citrus is almost universally present in various
forms. It has also been found to grow wild in Garo
hills and Siang district of Arunachal Pradesh.
Diverse forms of pummelo have been frequently
observed growing in lower hills of Assam,
Meghalaya and Tripura (Borthakur, 1993).

44.  Karl (1981), reported 17 citrus species with
52 varieties/types of citrus occurring in
NEH region having diploid chromosome
number 2N=18. Many edible species like
C. indica, C. ichangensis, C macroptera, C.
latipes are found to growing wild and semi-
wild in the region. Beside this, different
strains of citron ( C. medica ), sour
pummelo ( C. megeloxycarpa ), rough
lemon ( C. jambhiri ) and sour orange ( C.
aurantium ) are also reported to grow in
semi-wild condition in NEH region (Verma
and Ghosh, 1979).
 Area bordering Bangladesh have greater
variability in pummelo, Satkara and citron,

45. During the year 2000 to 2002 NRCC lead 4 exploration
tours to collect citrus genetic diversity from the region.
During the exploration, it was observed that C. latipes was
concentrated in and around Shillong. Total of 16
accessions mostly endangered and threatened citrus types
were collected.
Second exploration tour was undertaken in collaboration
with NBPGR, Regional Station, Umiam Meghalaya, . A
large number of promient citrus growing areas were
explored .A total of 79 collections were gathered from
these area.
Third explorations was conducted in West Garo hills of
Meghalaya, area of Assam and West Siang District of
Arunachal Pradesh to collect citrus germplasm funded by
ADB. A total of 40 accessions of citrus germplasm
belonging to different citrus groups viz., mandarin, rough
lemon, sweet orange, citron, pummelo and acid lime and
species viz ., C. pseudolimon (1), C. jambhiri (5), C. karna

46.  The Indian wild orange ( C. indica ) locally known
as Memon Narang are well protected in citrus
gene sanctuary
 Garo Hills of Meghalaya one of the promising
potential areas for locating citrus genetic diversity
in its best form. Citrus gene sanctuary Nokrek
Biosphere Reserve has maximum genetic
diversity of citrus. Three types of Memon Narang
( C. indica ) fruits from biosphere reserve area
were collected.
 Basar ,Arunachal Pradesh is another area rich in
citrus gene. Two indigenous sweet orange
materials namely Tasi and Soh Nairiang were

47. Fourth exploration was carried out in two
main citrus growing belts of the country,
where famous Sikkim mandarin and
Darjeeling mandarin are grown on
commercial scale. In Sikkim West, South
and East Sikkim districts were covered.
Whereas in case of West Bengal,
Kalimpong, Mirik, Darjeeling and Bijanbbari
areas of Darjeeling district were explored.
A total of 12 accessions of citrus belonging
to different citrus species were collected.
Besides mandarin, the other species like
rough lemon, Rangpur lime and citron were
observed growing in middle hills of

48. Citrus indica Citrus latipes Citrus kharna
Citrus
grandis
Citrus jambhiri Poncirus
trifoliate

49. Citrus medica Citrus
macroptera
Citrus
assamensis
Citrange
Citrus limon Citrus aurantifolia Citrus reticulata

50. Tasi Citrus pseudolimon

51. Exploration and collection of citrus
genetic diversity in Central India
In Central India four main field gene banks
are established, one at NRCC, Nagpur,
MPKV, Rahuri, Ahmednagar, Dr. PDKV,
Akola and Katol. Details of gerpmplasm
maintained in these gene bank were
reported by Singh . Nagpur mandarin and
Mosambi ( Citrus sinensis ) are
commercially cultivated. In these areas
NRCC leads three exploration tours first
exploration total of 33 accession collected.
In second exploration a total of 19
collections were made. Third accession in

52. Mosambi Nagpur mandarin

53. Exploration and collection of citrus genetic
diversity in South India
Southern region includes, Andhra Pradesh,
Karnataka, Tamil Nadu and Kerala. In south India,
acid lime ( C. aurantifolia .) is commercially grown.
Famous Coorg mandarin is grown in Coorg area of
Karnataka. Sweet orange ( Citrus sinensis .) cultivar,
Sathgudi is famous in Anantpur area of A.P. Other
commercially important indigenous types include
Gajanimma ( C. pennivesculata Tanaka), Kichli ( C.
maderaspatana Tanaka) and some wild mandarin
types viz ., Kodaithuli, Billikichili, Nakoor lemon, Mole
Puli (sour orange type) are found in the area. In these
areas most of the materials are maintained in three
main field gene bank AICRP, Tirupati and IIHR,
Bangalore and its regional station Chethalli. IIHR,
Chethalli had maximum exotic collection. In the year
2002 NRCC made 19 collections from Tirupati,

54. Satgudi Acid lime
Coorg Mandarin

55.  During the year 1999 to 2003 NRCC
collected 384 accessions of citrus from
different parts of country and most of
them were characterized based on
physico-chemical characters of fruits
(Singh and Singh, 2003). The evaluation
of citrus germplasm comprising of 15
species and 8 hybrids maintained at
ICAR Research Complex, Barapani farm
indicated a wide range of variability in
growth and physico-chemical characters
within the different species and types
(Sheo Govind and Singh, 2002).

56. Conclusion
The present situation of citrus genetic
diversity is alarming as enormous
destruction in the natural habitat is taking
place to fulfill various requirements of man
kind. Special drives need to be launched in
the remote areas to maintain a parallel
repository of germplasm ex situ, so that if a
diversity is extincted the species will be
available for future utilization.
At the same time every attempt should be
made to conserve the purity of the existing
germplasm in situ. Since some wild and
rare citrus species (like Citrus indica )
accessions failed to conserve in filed gene

57. References
 1. Haribabu, R., Rajput, C.B.S.(1999) Citriculture.
Kalyani publisher, New Delhi.
 2. Singh, I.P., Singh, S.(2006) Exploration,
collection and characterization of citrus
germplasm - a review. Agric. Rev ., 27 (2) : 79 -
90
 3 http://en.wikipedia.org/citrus fruits