Division of Plant Genetic Resources
The Division, since its inception in 1979 has been involved in Exploration, Introduction, Exchange, Evaluation, Characterization and Conservation of horticultural PGRs. A total amount of 22,080 accessions have been introduced in fruits, vegetables, ornamentals & Medicinal and Aromatic Plant species, besides enrichment of germplasm from wild sources through exploration missions. While evaluation and characterization of genetic resources was carried out in collaboration with the breeders of the commodity based divisions, a major thrust was focused on ex situ conservation of seed and pollen, for which infrastructure facilities were created through a UNDP project.
Protocols were optimized for short, medium and long term conservation of vegetable seed material and pollen of fruits, vegetables, ornamentals & Medicinal and Aromatic Plant species. Long term cryogenic preservation in these crops was accomplished and for the first time in India, a POLLEN CRYOBANK was established, which was featured in the LIMCA BOOK of RECORDS-2001. With the support of NATP, a program on exploration and collection of plant biodiversity of relevance to horticulture was successfully completed with collections derived from the Western Ghats, resulting in establishment of a Field Gene Bank (FGB) of 5300 accessions. Besides, the Institute has been supporting establishment of FGBs for Mango, Guava, Jackfruit with the funding support of other agencies.
The Head of Division since inception is listed below
- Dr.S. Ganeshan (present Head (A))
To act as a regional center for acquisition and management of indigenous and exotic horticultural plant genetic resources (PGR), and to carry out related research and human resource development for sustainable growth of horticulture in the country.
- To plan, organize, conduct and coordinate exploration and collection of desired indigenous and exotic PGR of relevance to horticulture.
- To undertake introduction, exchange and quarantine for augmenting horticultural PGR.
- To characterize, evaluate, document and conserve horticultural crop genetic resources and promote their use in collaboration with other national organizations within and outside ICAR system.
- To develop genomic tools, technologies, and approaches to discover and validate the functional genes of importance in germplasm of horticultural crops.
- To develop bioinformatic tools for exploitation of genomic information for enhanced utilization of horticultural PGR.
- To develop information network for effective utilization of horticultural PGR.
- To conduct research, undertake teaching and training, develop policy guidelines and create public awareness on PGR of relevance to Horticulture.
- To address and moderate policy issues related to Intellectual Property Rights (IPRs) with regard to horticultural crop germplasm
- Liason with National and International agencies working in area of horticultural germplasm
Present status of PGR activities at IIHR Bangalore
The PGR Division at IIHR Bangalore since its inception in 1978 has played an important role in crop improvement and diversification of horticulture in India through acquisition and distribution of the germplasm of fruits, vegetables, ornamentals and Medicinal and Aromatic Plant species in liaison with NBPGR. From being a section primarily concerned with plant introduction, exchange and conservation of gene pool components such as seed and pollen, PGR division today plays a key role in the overall management of horticultural PGR, comprising activities such as germplasm exploration, collection, exchange, quarantine, characterization, evaluation, conservation and documentation. The division was initially funded through a UNDP program for HR development and initiation of research in the area of germplasm conservation.
The Division has built up infrastructural facilities in the form of a full fledged seed storage laboratory, pollen storage laboratory having facilities for Cryopreservation of horticultural PGR. In 1996, the division developed facilities for in vitro conservation through an AP Cess funded project for optimizing in vitro conservation protocols for grape germplasm. Further support was provided to the division from 1999-2003 through an NATP Plant Biodiversity project, during which period the cryogenic and in vitro conservation facilities were strengthened, besides receiving support for plant germplasm exploration of species of relevance to Horticulture, from the Western Ghat region. It was during this period, IIHR developed a FGB facility for over 100 species of horticultural importance, well recognized and appreciated by NBPGR, which also led to identification of IIHR as NAGS for tropical & subtropical fruits.
The Division was is also carrying out its mandatory baseline PGR activities related to introduction and exchange indigenous and exotic germplasm of horticultural crops in liaison with NBPGR.
Achievements so far
Plant germplasm is an important natural resource and plays a vital role in the sustainable development of horticulture. A wide genetic base is essential for the development of new genotypes capable of surviving under heterogeneous environment. Management of genetic resources draws a major attention in farming and current emphasis is placed especially in areas such as exploration and collection, introduction, evaluation, characterization, documentation, and conservation of valuable genetic diversity in different horticultural crops. Keeping in view the importance of plant genetic resources, the section of Plant Genetic Resources has been upgraded to the Division level in 1999 to give fillip to the research in the area of genetic of resources management. Since then, the division has been working to evolve strategies for sustainable management of genetic resources of various horticultural crops, comprising fruits, vegetables, ornamental and medicinal crops.
I. EXPLORATION AND COLLECTION OF GERMPLASM
Exploration and collection missions were undertaken covering various parts of Southern India to collect wild as well as cultivated but untapped genetic resources of various horticultural crops.
1. Exploration and collection mission to Maharashtra
The districts covered were Pune, Satara, Kolhapur and Rathnagiri. A total no of 50 accessions of cowpea, dolichos, French bean, amaranth, brinjal and cucurbits were collected. A wild relative of the Vigna unguiculata (Vigna marina) was collected from Shivaji University, Kolhapur (it is distributed in Nicobar island). Collection from Gowal village in Rathnagiri district is cultivating specialty vegetable in cowpea and brinjal and germplasm of the same were collected.
2. Exploration and collection mission to Dharwad region of Karnataka
Places of collection were Dharwad, Gadag, districts and particularly Hulikoti, Gokak, Ghataprabha, Kabbur and Hukkeri market. A total of 28 germplasm were collected including amaranth, brinjal, dolichos, cowpea, cucurbits, tomato, and okra. Many local varieties of brinjal like Malapur local, Kuduchi local, Betegere local were collected. A Visit was made to growers field in Banavasi, Sirsi, Uttara Kannada, and collected four different lines belonging to Kew and Queen cultivars. Two variants in Kew cultivar, one brought from Punalur and the other from Thrissur were also collected. A survey was conducted in and around Sirsi, Sagar, Siddapur and Ullur in North Kannada district for mango trees used for pickling. Some of the lines collected (local names) are Kadigai, Karishad, Chandrama, Kempigunde, Gundappe, Maitri, Gangappe, Magemavu, Kadakeri local, Chinithotta, Dombesara, Kelaginamane, Yellare, Siddapura, Jeerige midi, Kanchape, karpurappe and Saadappe.
3. Exploration and collection mission to Tamil Nadu and Pondicherry
Districts covered were Cuddalore, Villupuram and Pondicherry union territory. Many local varieties of brinjal were collected viz. Annamalai University local, Palur local. In some pockets of pondicherry district, local brinjal and local red onion were also collected.
A visit to Parassara forest area resulted in collection of two pineapple lines and at HRS, Pechiparai, collections of two lines of pineapple lines one cultivar of jack (PPI-1) and Myristica fragrans were made.
An exploratory mission to Tirunelvi was undertaken for survey of off season mango and medicinal plants covering Parassala, Kanyakumari, Tirunelveli, Tenkasi, Tuthukudi, Vallanad and surrounding areas. At Prassala, a local mango variety namely Chengavarikkai was collected. From Hoticulture farm, Kanyakumari, scion sticks of local varieties such as Surankudi, Kalkaichi, Nadan, Mohandas, Vettaiyasurankudi, Chinnakkothu, Panchavarnam, Kalkandu and Panickanadan were collected. Four established varieties of aonla were also procured. One medicinal plant locally known as Vaadhamudakki was collected. Two sets of Tirunelveli Senna were collected from Senna Exporters of Tirunelveli. Exploration at Vallanad hills resulted in location of one line each in Aloe and Shatavari. At Ambasamudram, one line each of glory lily and Hemedesmus were also collected.
4. Exploration and collection mission to Kerala
An exploration mission was undertaken to Northern Kerala covering districts of Calicut, Malappuram of Palghat to collect indigenous ornamental germplasm. The species collected were Alpinia calcarata, Selaginella lepidophylla, Kaempferia rotunda, Cholorophytum laxatum Curcuma longa, Cucurma oligathis and Globba vivipara, Alpinia species, Curcuma aromatica, Curcuma cesia Costus speciosus ,Kaempferia species, Hedichium coronatrium, Curcuma aruginosa Cucurma ecalcarata, Alpinia calcarata and Alpinia zerumbet .
A mission was undertaken to Thiruvananthapuram and Kanyakumari to collect fruit and medicinal plants. Exploration to forests around Palaruvi, Tenmalai and Ariyankavu resulted in collection of Gardenia gummifera, Andrographis wightiana, Rauwolfia serpentine, Stychna calibryanum, Cycas circinalis, Alstonia veninata, Cinnamomum malabaricum, Elephantopus scabet, Piper longum, Mangifera indica and Celasterous paniculata. Procured Aloe vera (3 types), Bacopa monneri (4 accessions), Centella asiatica (5 accessions), Piper betel (3 accessions), Andrographis sp., Plumbago rosea, Asparagus racemosus and seeds of Gloriosa superba, Andrographis paniculata, Garcinia gummigatta and Mucuna grandis from TBGRI, Thiruvanathapuram. Lines of lemon grass, Asparagus racemosus, Jatropha glandulifera, Mucuna pruriens, Mucuna atropurpuria, Mucuna cochinensis and Stychna potatarum were also procured.
A total of 12 fruit species common to South Kerala namely, Antidesma ghaesmbilla (Black current), Salacia chinensis, Salacia beddomei, Flacourtia Montana, Syzygium zeylanicum, Elaecarpus serratus, Chrysophyllum cainito (Star apple), Flacourti (lovi-lovi), Averrhoa bilimbi (Bilimbi), Averrhoa carambola (sour type Carambola), Psidium guineense, Aporusa lindleyana and Psidium littorale, from forests were procured from TBGRI.
The exploration to Vaniampuzha forest area resulted in collection of Cyclea peltata, Asparagus racemosus, Gloriosa superba, Mucuna pruriens, and Piper longum. Suckers of Aloe abyssina were procured from the Herbal garden of KFRI. Collected plants and tubers of Aloe from breeding block of KAU and farmers field.
5. Exploration and collection mission to Andaman and Nicobar Islands
Fruits of Mangifera andamanica and M. camptosperma were collected. The other species collected were wild Jamun, wild artocarpus, Ciba pentandra (Silk cotton tree) and Oroxylum indicum, large oval shaped fruits of Aegle marmelos. Fruits of Mangifera griffithi and Garcinia sp were collected. Two plants each of Myristica andamanica and Cycas rhumphi were also collected. A naturally growing Mucuna plant was also located and dried fruits were collected. Betel vine plants were collected which looked like cultivated as well as wild. The leaves were more pungent to chew. Also several medicinal plants were collected.
6. Exploration and collection mission to Goa
An extensive survey of the North Goa covering Balki, Savai Verum, Borin, Khandapar, Marcela, Khandola and Bicholim was undertaken. Kokam trees were found to be fairly distributed all over the jungles of Goa with wide variations in vegetative and fruit characteristics. In all, 33 trees were located and studied in detail. Fruit samples were collected for further studies. Based on preliminary observations, two trees could be considered as elite trees.
7. Exploration and collection mission to parts of Karnataka
Exploration was carried out in the Devarayana Durga forest range of the Tumkur district of Karnataka and 18 medicinal plants were collected. Similarly, 12 medicinal plants were collected from Koodluthirtha and Agumbe area. Kokam trees were collected from Puttur in Dakshin Kannada district. A Survey was undertaken to Puttur, South Canara to collect variability in Kokum trees. Five different hermaphrodite trees were located and studied from private orchards in Alakku Majalu, Marial Puttur and Savanuru. Two elite trees with big sized very dark purple coloured fruits and high yield and one tree with early bearing habit were collected from a private orchrd at Sediyapu, which has plenty of variability for kokum trees.
8. Collection mission to Andhra Pradesh
A Survey was undertaken to Adilabad, AP and collected fruits and scion sticks of Gourani mango, which has good canopy and good fruit yield from Dongragaon of Gudihathnoor mandal. In Narayanpur village collected Gourani types with pinkish shoulder, golden yellow and very early maturing types. A similar survey was undertaken to Emboye village of Bethamcherla (AP), known for excellent quality Banganapalli and collected local varieties Narasu and Reddipasand, one of which is claimed to be better than Banganapalli in quality. Fruits and scion sticks of four such types including golden yellow colour with good quality fruits and another with purplish red colour were collected.
II. PLANT INTRODUCTION
Besides explorations, the Division has also been coordinating with crop divisions in introduction of germplasm both from indigenous and exotic sources. About 128 accessions of various horticultural crops were introduced since 2001 which includes vegetable crops from AVRDC, Taiwan and fruit crops from Australia, S. America, USA and Uzbekistan.
III. GERMPLASM CHARACTERIZATION
A. Morphological characterization
Guava: Total germplasm collection stands at 70 accessions, of which 60 accessions were characterized morphologically as per standard descriptor. Wide variability was recorded for fruit and fruit component characters. Based on characterization donor parents were identified for different traits.
Sapota: Out of 32 accessions, morphological characterization was carried out for 25 accessions as per standard descriptor. The fruit parameters showed wide variability for fruit length, fruit width, fruit weight, pulp percentage, pulp colour etc. among different accessions.
Mango: As per the IPGRI descriptor morphological characterization was carried out for 250 accessions. The genotypes expressed wide variability for growth, leaf, flower, fruit and quality parameters. Based on characterization and evaluation donors parents were identified for different horticultural traits.
B. Molecular Characterization
DNA fingerprinting, genetic diversity analysis and marker assisted selection using the frontline DNA technologies are being investigated.
Arka Komal, Arka Suvidha, Arka Bold, Arka Anoop
Arka Anamika, Arka Abhay
Arka Kalyan, Arka Niketan, Arka Pitamber
Arka Rajhans,Arka jeet
Arka Chandan, Arka Suryamukhi, Arka Vikas, Arka Saurabh, Arka Meghali, Arka Ahuti, Arka Ashish, Arka
Abha, Arka Alok, Arka Abhihit, Arka Shrestha
Arka Neelkanth, Arka Kusumakar, Arka Keshav, Arka Shirish
Arka Jay, Arka Vijay
A. Shreshta and A. Abhijit
Genetic diversity analysis
French bean (Phaseolus vulgaris L.)
The molecular diversity of French bean 48 accessions collected from 7 different agro-climatic zones of India were evaluated using RAPD markers. The molecular dissimilarity values ranged from 4 to 45% suggesting a narrow genetic base within the Phaseolus vulgaris cultivars. Principal component analysis showed two major clusters similar to the dendrogram of cluster analysis.
The genetic diversity of onion genotypes and hybrids were assessed using DNA markers. Twenty four breeding lines of onion were selected based on colour of the bulb, disease resistance, bulb type (single or multiplier), type of pollination and hybrids. Randomly selected eleven and thirteen sets of breeding lines were studied separately to know the genetic similarity using DNA markers. For the eleven breeding lines, seven random primers generated 42 RAPD loci of which 35 RAPD loci were polymorphic (81.89%). Among the thirteen breeding lines, five random primers generated 37 RAPD loci of which 33 RAPD loci were polymorphic (86.66%). Out of the seven primers OPA 18 showed the highest genetic polymorphism of 100% indicating that the primer can be used for fingerprinting. In the other thirteen breeding lines, OPC 05 and OPC 06 produced 100% polymorphism. Each cluster in the dendrograms belonged to their respective groups. The information generated can be used to improve the agronomically important traits.
Ornamental Crops: DNA fingerprinting of released varieties was done for the following ornamental crops using ISSR/SSR markers to establish genetic distinctness of the varieties and to protect plant breeder’s rights. The following varieties have been characterized using DNA markers.
Rose: DNA profiles of three Varieties viz., G S Randhawa, Kiran and Nishkant developed using SSR and ISSR markers
Crossandra : DNA profiles of Arka kanaka, Arka ambara, 2005-1 and 2005-2 generated using ISSR markers..
Carnation: DNA Fingerprinting of Variety IIHR P-1 (Arka Flame) was carried out using SSR markers
Tuberose: DNA profiles of Sringar, Suvasini, Prajwal, Vybhav, Arka Niranthara were generated using ISSR markers.
China Aster: DNA profiles of Poornima, Shashank, Kamini were generated using ISSR markers.
Gladiolus: Molecular characterization and genetic diversity analysis carried out for 30 Genotypes. Cluster analysis based on Ward’s method showed two major clusters. First cluster consisted of IIHRG-4, IIHRG- 9, IIHRG- 5, Aarthi, Sanjeeveni, Tilak, Dr.Flemming, Wild Rose, Shobha, Shakti, IIHRG -6, IIHRG -8 and IIHRG – 12. The second cluster consists of Apsara, Basant bahar, Arka kesar, Poonam, Sapna, Sagar, Sindhur, Darshan, Kum Kum, Gladiolus callianthus, IIHRG- 11, Shirley, Psittacinus (local) , IIHRG- 10, Pink friendship, Candy man and Dhanvantri. Genotypes Dhanvantri and candyman can be considered as potent parents for further improvement programme. The polymorphic primers identified provide a core set that will be useful for fingerprinting gladiolus cultivars/hybrids/species. Gladiolus callianthus, a fragrant genotype can be utilised for breeding programs.
Mucuna::Genetic diversity analysis has been carried out in the accessions of Mucuna pruriens. RAPD profiles of the 22 accessions taken for study were generated with four random primers and its pair wise combinations. The primer generated 152 RAPD loci of which 113 were polymorphic. The level of polymorphism generated was 74% among the accessions. Among the individual primers used OPA 2 produced maximum polymorphism of 65% and in pair wise combination OPA1+ OPA 2 generated 94 % polymorphism. It was found that adopting the pair wise primer combination enhanced the level of polymorphism as compared to the individual primer. The dendrogram based on Ward’s method grouped the 22 accessions into four clusters and one lone cluster. The lone cluster belonged to the genotype MP-5 that has a high L-DOPA content.
Identification of Zygotic seedlings using molecular Markers
Mango: Distinguishing zygotic seedling in polyembryonic (PE) varieties of mango using molecular markers is in progress in collaboration with the division of Fruit crops.
Minor fruit crops:
Jack fruit (Artocarpus heterophyllus): Molecular characterization and genetic diversity analysis in under utilized fruit crop namely jack fruit (Artocarpus heterophyllus) is in progress for identifying trait specific germplasm to establish working collections.
Genetic stability/fidelity testing using molecular markers.
- PCR protocols were optimised and identified ISSR/SSR primers for genetic fidelity testing of tissue culture raised plantlets of Anthurium, Carnation and Gerbera.
- Genetic fidelity of in vitro raised plantlets of carnation vis-a-vis mother plant was assessed using 16 SSR and 10 ISSR. The percentage of polymorphic bands in SSR and ISSR analysis were respectively 7.69% and 5.88% for the 16 clones and mother plant. Microsatellite markers detected more polymorphism in the in vitro clones compared to ISSR markers revealing the ability of these markers to detect subtle variation at the molecular level.
- A field evaluation trial indicated that Bird of Paradise is a promising crop for southern dry zones of Karnataka. Identified Bird of Paradise Elite lines with specific attributes, such as plant height, spike length, high flower to leaf ratio, clump production, high spike yield and more florets/spike, which can be used as clonal selections or used for as potential parents for crop improvement programmes.
- Generated mutant population in bird of paradise by gamma irradiation for increasing variability and isolating mutants with desirable traits. Initial evaluation indicated a wide range of variability with respect to plant height, number of leaves/plant and clump production and spike yield.
II. GERMPLASM EVALUATION FOR RESISTANCE TO INSECT PESTS
Germplasm of fruit, vegetable and ornamental crops, introduced and being maintained at the institute, was evaluated to find resistance sources to major insect and mite pests. The resistance or susceptibility of genotypes was also correlated with different morphological and biochemical parameters.
Screening of pests from voucher samples collected from explorations and collections
Mango: Leaf and fruit samples from exploration missions to South Andaman Islands were screened for insect pest damage. Leaf damage up to 25% was observed in samples collected from Baratang Island. All accessions were free from stone weevil damage. Leaf and fruit samples from exploration missions to Middle and North Andaman Islands were screened for insect pest damage. Leaf damage up to 46.58 % (8-10%) was observed.
Jackfruit: Average leaf damage of 26.3% (Range-18.18-37.50%) was recorded from two voucher samples.
Jamun: Average leaf damage of 45.48% (Range 37.35-56.66 %) was recorded from 3 voucher samples.
Dharwar and Kittur
Jamun: 16 Leaf and fruit samples from Dharwar and Kittur recorded leaf damage of 42.38 % (4.16%-90.9%).
Kaveripattanam and Paiyur, Tamil Nadu
8 Leaf and fruit samples from Kaveripattanam and Paiyur were screened for insect pest damage. Average Defoliator damage was 44.73% (26.40-82.91%) and Leaf folder damage was 91.62% (33-100%).
Leaf and fruit samples (32) from Belgaum, Khanapur and border areas of Maharashtra were screened for insect pest damage. Damage by leaf gall (14.28 %) caused by Psyllids was observed.
Monitoring and recording of pest load on domesticated, under utilised fruit species and medicinal and aromatic plants
Under utilised fruit species: In Flacourtia montana, larvae and pupae of leaf feeder Phalanta phalanta was observed assuming serious pest status.
In Aegel marmelos,
Domesticated fruit species: In Baccaurea courtallensis leaves damaged by mirid bugs, Helopeltis sp. On Aegle marmelos, leaf feeder beetle, Clitia picta causing serious leaf damge was observed. Other pest species viz., citrus butterfly, Papilio demoleus, (0.5 larvae/shoot), and an ash weevil (Mylloceros sp) (22.5 -34.6% with mean of 28.55% leaf damage) were recorded. On Psidium spp., sporadic incidence of green scale (Coccus viridis), Bag worms, Spiraling whitefly (Aleurodicus disperses), Termites and Hairy caterpillar (Euproctis sp) were recorded. Besides these, activity of honey bees (Apis dorsata, and A. florea) was also observed on flowers of both the Psidium species.
Medicinal and Ornamentals: In Amla, leaf folder, Gracillaria acidula causes 9.56-38.53% leaf damage. In Bird of Paradise, Lymantrid larvae, Mealy bug (Ferrisia verghata) and 60% parasitization by Anesius advena was recorded
Mango: Stone weevil damage on seedling population of polyembryonic varieties of mango viz., Muvandan, Vellaikulumban, Mylipilian, Nekkare, Kensington, Olour, Prior, Moreh varied from 0 (Nekkare, Mylipilian, Prior, Manipur, Moreh)- 92.15 % (Olour) with a mean16.98%.
Seedlings of seven polyembryonic varieties of mango were examined for the infestation of mango scale (Aulacaspis tubercularis) under net house conditions. Variety Moreh was initially free from Scales but showed infestation after 3 months to the extent 25.40%. Bappakai recorded 82.26 % infestation. The damage caused in other varieties varied from 27.55 % (Kensington pride) to 48.49% (Vellaikulumban). Among the infested plant parts, lower surface of the leaf near the petiole was most affected and the damage varied between 30 and 48 %. After two weeks of spray with Imidacloprid @ 0.3 ml/L controlled the pest infestation in all varieties except Bappakai, where resurgence of the pest incidence was observed.
Pollinator diversity in mango germplasm: Recorded pollinators in nine varieties and one species. (Amrapali,Banganapalli, Kalepad, Prabhat Shankar, M. odorata, Langra, Himsagar, Lajjat Bakshi, Rumani, Totapuri). Apis florea, A. cerana, Eristalinus arvorum, Chrysomya megacephala, was found to be major pollinators across varieties in consecutive years. Exception observed is the foraging of rock bee, Apis dorsata (on Amrapali). Pollinators under protected cultivation: Introduction of honeybee colonies was not successful. Bees congregate to the corners of roof and die. However under net house, they were effective. Alternatively Calliphorid flies are being evaluated with watermelon.
IV. GERMPLASM CONSERVATION
Pollen cryobank conserves NGD of important horticultural crops. Long term conserved pollen in the form of nuclear genetic diversity (NGD) of citrus, papaya, grape, mango, tomato, eggplant, onion, capsicum, rose, gladiolus, gerbera, carnation and RET species of medicinal plants are continued to be cryopreserved in liquid nitrogen. The pollen cryobank was maintained and managed by periodic replenishment of the cryogen, for maintaining a constant cryogenic temperature throughout the storage duration.
2 In- vitro Conservation
Protocols have been optimized for 23 horticultural crops, which are being conserved under normal and reduced culture conditions. Vitroplants of Jackfruit accessions have been successfully conserved for 4 years under standard culture conditions prior to first subculture. While more jackfruit accessions are accessed in vitro, 4 citrus accessions are maintained in vitro and conservation attempts has resulted in maintaining vitro plants under reduced culture conditions for 6 months.
3. Seed Conservation
Seed conservation is aimed at maintenance of high seed quality in terms of viability and vigour for various periods. High seed quality was maintained for 20 years in onion, radish, French bean, cluster bean, watermelon, pumpkin and capsicum; for 15 years in chilli, carrot, tomato, brinjal, long melon, amaranth, bottle gourd, spinach beet and muskmelon and 8 years in cucumber and marigold by using moisture impervious containers and storing them at sub-zero temperature (-200C). Seeds preserved well in polyethylene bags too at low temperature (50C), which can also be used for medium term storage (<10 years) without affecting the seed quality. High seedling vigour in terms of growth parameters was exhibited in low temperature stored seeds. Further, seedlings emerged from stored seeds were healthy and normal. There were no changes in plant characteristics on germination of stored seed germplasm. A low cost storage technique such as modified atmosphere packaging of seeds with nitrogen or carbon dioxide showed relatively higher seed storability. Seed viability was greater with nitrogen in ridge gourd, garden peas and bitter gourd and with carbon dioxide in Knol Khol, cabbage, French bean and cluster bean under ambient conditions.
4. Field conservation
The division has been maintaining several accessions of different fruit crops in Field Gene Bank viz., guava (70 accessions), ber (30), jamun (12), custard apple (14) and fig (6). Collection of medicinally important species made during the previous years are being maintained in the form of FGB simulating wild situations under captivity in the form of a plant biodiversity block maintaining over 100 species collected from the Western Ghat region.