Citrus is the third most important fruit crop of India with several
species recorded to have originated especially in parts of Northeast.
India with World's third highest Citrus production after China and
USA is regarded as home of Citrus due to the presence of vast genetic
diversity of important species.
Citrus fruits are rich in antioxidants and have nutraceutical properties
which make this fruit a prime choice of daily diet in developed
countries. Genetic resources are the backbone of any crop
improvement programme and for a diverse fruit like Citrus their
importance is incredible. Hence, in the national context management
of genetic resources of citrus assumes immense significance.
Citrus genetic resources spanning across 5 major groups namely,
Acids, Oranges, Pummelo-grapefruit, Mandarins, Wild and semi-wild
species and other related genera, hold great economic significance
for Indian fruit industry. India, a natural home of several Citrus
species harbours vast reservoir of diverse types/forms.
Genetic diversity of Citrus is mainly concentrated in the Northeastern
and Northwestern part of India. Study on genetic resources of Citrus
in Northeastern India indicated the presence of 23 species, one
subspecies and 68 varieties, thus according this area a special status
as a treasure house of Citrus germplasm.
• To protect these invaluable genetic resources of citrus, NBPGR
(ICAR) took initiative way back in 1981 by establishing the
"Citrus Gene Sanctuary", probably first of its kind in the
World, in the Garo hills of Meghalaya. It is endowed with highly
specified microclimate and is a part of buffer zone of Nokrek
Biosphere Reserve in Meghalaya. With only 12-13% of the
earth's surface devoted to protected areas and other
conservation areas, it is understandable that all species
diversity cannot be secured in them. Ex situ conservation, with
several options, are thus required to be adopted. Introduction
of desirable Citrus germplasm into country by NBPGR and
other organizations have enriched the diversity and
strengthened the Indian Citrus Industry.
• Seed banking is one of the most powerful and practical ex situ
conservation tools available to combat the loss of biodiversity
while complementing the in situ conservation.
• NBPGR has thus worked with integrated approach by
cryobanking of seeds, embryos and embryonic axes and a
cryobase collection of about 700 accessions has been
• Rich genetic diversity of fruits exists across the tropical and sub-tropical
regions of the world, with more than 500 species of fruits estimated to be
found in Southeast Asia alone (Rao and Bhag Mai; 2002).
• India is one of the 12 mega diversity rich countries of the World possessing
three hot spots of biodiversity (Conservation International-Biodiversity
hotspots: http: //www. biodiversityhotspots.org).
• Northeast India fans under the "Indo-Burma Region" of hot spot of
biodiversity, which is the richest and one of the most threatened places for
plant life on the earth. Several Citrus species and their natural hybrids have
been reported to originate and exist in this area; however, this vast
indigenous Citrus diversity of India has not been used to its full potential for
Citrus improvement programmes.
• Any species or cultivar lost from nature is a loss of unique genetic
information contained in it that had evolved over several generations.
• As per the International Union for Conservation of Nature and Natural
Resources (IUCN) norms seven Indian Citrus species are endangered as
indicated by threat perception analysis (Singh and Singh, 2003).
• These species are C. indica, C. macroptera, C. latipes, C. assamensis, C.
ichangensis, C. megaloxycarpa and C. rugulosa.. Sustainable in situ and onfarm conservation is possible with active synergies with farmers,
communities and national institutions. Role of farmers as active partners,
conservator, promoter and custodian of local citrus diversity are needed to
• Hodgson (1965) placed various citrus fruits into five groups:
based on their fruit characters:
(1) Acid members group: 7 species, i.e.
C. medica L., C. limon (L.) Bunn. f., C. jambhiri Lush., C. limmetta
(Risso) Lush., C. karna Raf., C. aurantifolia (Christm.) Swingle, C
latifolia Tanaka and C. limettioides Tanaka.
(2) Orange group: 5 species, i.e.
C. aurantium L., C. myrtifolia Raf., C. bergamia Risso, C
natsudaidai Hayata and C. sinensis (L.) Osbeck.
(3) Pummelo-grapefruit group: 2 species, i.e. C. maxima (Burm.)
Merr. and C. paradisi Macf.
(4) Mandarin group: 6 species, i,.e.
C. reticulata Blanco, C. unshiu Marcov., C. deliciosa Tenore, C.
tangerina Hort. ex Tanaka, C. reshni Tanaka, and C. nobilis Lour.
(5) Other species group: 11 species, i.e.
C. macroptera Montr., C. hystrix DC., C. latipes (Swingle) Tanaka,
C. macrophylla Wester, C. limonia Os beck, C. pennivesciculata
Tanaka, C. maderaspatana Tanaka, C. junos Seibold, C.
ichangensis Swingle, C. indica Tanaka and C. madurensis Lour.
Centres of Origin:
• Citrus is believed to have its primary centre of origin in
South and South- East Asia i.e. Malayan Archipelago to
China and Japan, and southward to Australia and also
to New Caledonia and New Guinea
• The Citrus belt of the world extends approximately 35°
N and 35°S latitude on either side of the equator. Citrus
fruits are widely cultivated throughout the tropical and
sub-tropical regions of the world,
• Probable centers of origin of twenty important Citrus
species based on various literature surveys are
Table 1 : The principal Citrus species with probable centres of origin in Asia
Probable centre of origin
C. medica L.
C. limon (L.) Burm. f.
C. aurantifolia (Christm.) Swingle
C.limmetta (Risso) Lush.
C. jambhiri Lush.
C. karna Raf.
C. reticulate Blanco
C. tachibana (Makino) Tanaka
C. indica Tanaka
Indian wild orange
C. maxima (Burm.) Merr.
C. megaloxycarpa Lush
C. aurantium L.
C. sinensis (L.) Osbeck
C. paradise Macf.
C. latipes (Swingle) Tanaka
C. macroptera Montr.
Polynesia and Malay
C. ichangensis Swingle
C. hystrix DC.
C. micrantha Wester
C. assamensis Dutta & Bhattacharya
C. pseudolimon Tan.
• The major citrus producing states and districts and
commercial cultivars grown in different zones of India:
1. North-western Zone:
Jammu & Kashmir (Jammu, Kathua, Udhampur and Rajauri)
Himachal Pradesh (Kangra and Sirmaur)
Punjab (Abohar, Fazilka, Faridkot, Batinda and Hoshiarpur)
Haryana (Sirsa, Fatehabad, Hisar and Bhiwani)
Rajasthan (Shriganganagar, Jhalawar, Bharatpur, Dholpur
and Sawai Madhopur)
• Commercial cultivars:
• Mandarin- Kinnow;
• Sweet oranges- Jaffa, Malta, Blood red, Valencia, Hamlin and
• Acid lime - Kagzi lime, Vikram, Kagzi Kalan
• Lemon- Galgal, Eureka, Baramasi, Pant lemon 1, 2 and 3
• Pummelo- Chakotra
• Grapefruit- Duncan, Marsh seedless, Foster and Ruby red
2. North-eastern Zone:
– West Bengal (Darjeeling, Jalpaiguri, Midnapur and 24
– Assam, Arunachal Pradesh, Manipur, Meghalaya,
Mizoram, Nagaland, Sikkim and Tripura
• Commercial cultivars:
• Mandarin - Khasi mandarin, Sikkim or Darjeeling mandarin
• Sweet oranges - Malta, Tasi, Sohbitara, Soh-nariang, Mitha
chakola. Ruby, Blood red, Valanecia
• Acid lime - Kagzi lime, Vikram, Kagzi' Kalan
• Lemon- Assam lemon, Pant lemon and Chinara
• Pummelo- Kanapora, Batabi, Bhogote, Sah-myngor, Sagothra,
• Lambura and Der-tawk
• Grapefruit- Duncan, Marsh seedless and Ruby red
• Others- Satkara
3. Central Zone:
– Madhya Pradesh (Mandsaur, Shajapur, Chhindwara,
Khandwa and Hoshangabad)
– Maharashtra (Amravati, Nagpur, Akola, Aurangabad,
Wardha and Yevatmal)
– Orissa (Ganjam), Uttar Pradesh and Bihar
• Commercial cultivars:
Mandarin- Nagpur mandarin
Sweet oranges- Mosambi, Malta
Acid lime-Baramasi, Vikram, Laldevi, Pramalini, Sai Sarbati
Lemon- Bhadri lemon, Pant lemon
Pummelo- Chakotra, Mahatabi, Gagar
Grapefruit- Saharanpur special, Duncan, Marsh seedless Ruby
Area of cultivation
Nagpur mandarin, Kinnow mandarin, Honey, Wilking, Maharashtra,
mandarin, Fewtrell's Early, King, Willow leaf, Pradesh,
(C. reticulata) Khasi
mandarin, Orlando, Temple, Fairchild, Fremont, states, Darjeeling, Sikkim,
mandarin, Ponkan, Kamla, Australia, Fox Coorg
ButwaI, mandarin, Fortune, Afourer
Sweet orange Mosambi, Satgudi, Jaffa, Hamlin, Malta, Valencia late, Maharashtra,
Sonamitri, Loyalpur Pineapple, Blood Red, Washington Pradesh,
S1, Loyalpur S-2, Naval, Olinda Valencia late, Delta Rajasthan, Northeastern
Mitha chakola, Tasi, Valencia, Vanale, Moro, Rhode Red states
Valencia, Parent Naval, Declarbe
Sweet Orange, Vaniglia Sanguigno,
Sweet Orange, Teneriff, Tardiff,
Seleta, Aspal Ornage, Joppa
(C. Hill lemon, Assam Eureka lemon, Italian
lemon, Lesban lemon,
Seville, Harvey lemon
Assam and Northeastern
lemon 1,2,3, Bhadri no.252,No.302, Villa
Area of cultivation
Gagar, Sweet China, Royal, Triumph, Northeastern states, Foothills
Red flesh, White Foxey
flesh, Pink fleshed,
Himalayas, parts of Bihar,
Uttarakhand, Uttar Pradesh,
lambura, Ser tawk,
Saharanpur special, Duncan, Frost marsh, Marsh Northeastern Region, and
Champa seedless, Ruby red, Foster pink, parts
Red blush, Thompson seedless, Himachal Pradesh, Punjab,
Bira jora, Pati jora, Etrong citron
North-eastern states, foot hills
of North-western and
Central Himalayas, Punjab,
and peninsular region of India
Mitha jora, Tayum,
Areas of cultivation
Jatti-khatti, Jullandhari khatti, EC-25833, Florida North-eastern and foot hills of
Jambhiri, Mithi, Renuka lemon, rough 8748, Rough North-western and Central
Wynad rough lemon, Gol nirnbu, lemon, South Africa, Himalayas,
Kata jamir, Sinduri lemon, Naity Italian rough, Esteus southern peninsular region
thuli, Cleopatra mandarin, Field gene banks, gardens,
backyards and orchards in
Andhra Pradesh and other
parts of India
dragon, Field genebanks, NRCC,
Pomeroy, Rubidoux, Nagpur, PAU RS, Abohar and
EC- 31974, Dweat
Areas of cultivation
Karun Jamir, Sohmyndong, Seville orange
(C. aurantium) Mole kaipuli
Rangpur Lime Rangpur lime L- 19, Sharbati EC-115795,
Northeastern India, Parts
lime, Kusai lime, Kole jamir Florida Rangpur- of Central and South
Field genebank of NRC
cv. Field genebank of NRC
Troyer citrange Citms, Nagpur Field
genebanks of NRCC,
Carizo, Savage, Nagpur,
Abohar and other field
• In India Citrus genetic resources are being managed by multiple agencies
such as research institutes of Indian Council of Agricultural Research (ICAR),
State Agricultural Universities and also by the State Horticultural Farms, and
Fruit Research Stations.
• Besides these several private nurseries, orchards, gardens, parks etc. which
are owned by progressive farmers and public enterprises are also
maintaining Citrus germplasm as field collections
• In India National Research Centre for Citrus (NRCC), of ICAR, located at
Nagpur in Central India is the only dedicated institute for Citrus research,
development and extension. This Centre has also been designated as
National Active Germp1asm Site (NAGS) for Citrus by NBPGR.
All India Coordinated Research Project (AICRP) on Tropical Fruits
(Citrus) of ICAR with its Network at nine centres at SAU's and ICAR institutes
in various agro-ecological regions of India has been taking up work on
genetic resources management, crop improvement, crop production and
crop protection. Since last several decades crop specific responsibilities for
multi-location evaluation and improvement work has been assigned to
• World Status of PGR:
which was published recently in the year 2010 to update the
information in the first report, indicated 29,690 accessions
of Citrus in the World. For better management of World
Citrus genetic resources for conservation and utilization,
FAG in 1997, constituted the Global Citrus Germplasm
Network (GCGN) to involve national institutions and existing
regional and inter-regional citrus networks such as, the
Inter-American Citrus Network (IACNET), MECINET, IACNET,
CLAM and NeSCRA.
• The main objective of this network was to link germplasm
related activities undertaken in the different parts of the
World. However, the present status of existence of the
GCGN could not be ascertained as the last proceedings of
GCGN countries meeting available on various Citrus related
websites is of the year 2000.
Table3: Number of collections of Citrus species made from various States during explorations by NBPGR and NAAS
Andaman and Nicobar Islands