S. K. Malik

Collection and Characterization of Citrus indica Tanaka and C. macroptera Montr.: Wild Endangered Species of Northeastern India

Citrus indica and C. macroptera are the wild endangered species of Citrus occurring in northeastern India. Surveys were undertaken in this region for ascertaining distribution, studying variability and for collection of germplasm of these two species. C. indica, an endemic species of this region, was collected from the Citrus Gene Sanctuary located in buffer zone of Nokrek Biosphere Reserve in the Garo hills of Meghalaya. In addition, a putative natural hybrid of C. indica and C. limon was collected for the first time from the south Garo hills. C. macroptera had much wider distribution and was collected from Mizoram and Meghalaya states. In Jantia hills of Meghalaya, natural populations of this species are in a highly threatened state. The two species were unevenly distributed all over the explored territory. Morphological characterization of leaves, fruits and seeds indicated the presence of sizable variability within collected accessions of these two Citrus species. Indigenous technical knowledge gathered on the use and socio-economic importance indicated commercial potential for these two species in northeastern India. However, lack of cultivation of these species and clearing of forest cover at an alarming rate has led to an urgent need to adopt complementary conservation strategies to safeguard these species and to ensure their availability for future utilization. A major emphasis on developing methods for their propagation, multiplication and regeneration in in situ and ex situ conditions is required.

The cryopreservation of embryonic axes of two wild and endangered Citrus species

The cryopreservation of embryonic axes of two wild and endangered species, Citrus macroptera Mont. and C. latipes Tanaka, was attempted using air desiccation–freezing, vitrification and encapsulation–dehydration. Successful cryopreservation was achieved in both the species using these three methods. However, the two species responded differently to: the rate of drying and the degree of tolerance to desiccation following air desiccation–freezing; the response to loading duration following vitrification; and to the sucrose concentration during pre-culture following encapsulation–dehydration. C. macroptera was more tolerant to desiccation and freezing than C. latipes with recovery rates of, respectively, 87% and 64%. Recovery from encapsulation–dehydration was 62% for C. macroptera and 45% for C. latipes . In both species, the vitrification protocol gave a significant improvement in recovery rates: 92% and 77% for C. macroptera and C. latipes , respectively. The air desiccation–freezing protocol being a simple and practical technique is recommended for the cryopreservation of these two species.

Socio-economic importance, domestication trends and in situ conservation of wild Citrus species of Northeast India

Northeast India is rich in Citrus genetic diversity representing several wild and cultivated species. Besides commercially cultivated species, several wild, semi-wild and domesticated species namely Citrusindica, C.macroptera, C.ichangensis, C.latipes, C.megaloxycarpa and C.assamensis are found to grow in Northeast India. These species have great potential in improvement of Indian Citrus industry being source of genes for combating biotic and abiotic stresses. The natural diversity of these genetic resources is shrinking at alarming rate due to large scale deforestation, shifting cultivation practiced in these areas and climate change scenario in this important hotspot of biodiversity. Socio-economic importance of each species have been studied during surveys and interesting domestication trends were observed based on their cultural and economic significance, which led to “in situ on farm” conservation of C.indica, C.macroptera and threat to C.megaloxycarpa and C.ichangensis. Consequently, genetic resources of most of these species are facing severe threat of extinction necessitating policy interventions and adoption of dynamic conservation and management strategies. Species specific conservation strategy especially through “in situ on farm” conservation has been proposed with suitable sites in Northeastern Indian states based on population structure and suitability of habitat. Farmers’ support through “The Biological Diversity Act, 2002” and “The Protection of Plant Varieties and Farmers’ Rights Act, 2001” of India would bring the required impact on management of these complex genetic resources of Citrus. In the present study, we have documented the current status, socio-economic potential, domestication trends and associated traditional knowledge of these wild and semi-wild Citrus species occurring in Northeast India and enumerated suitable conservation strategies and desired policy interventions for their dynamic conservation and sustainable utilization.

Genetic diversity and traditional uses of wild apricot (Prunus armeniaca L.) in high-altitude north-western Himalayas of India.

Wild apricot ( Prunus armeniaca L.) is an economically important fruit crop for folk and marginal farmers and local tribal populations in the high-altitude difficult terrains of north-western Himalayas in Jammu and Kashmir and Himachal Pradesh states of India. This is a multi-purpose fruit tree species which, besides its fresh edible fruits, is preserved for use in diverse ways depending upon the type of cultivar. Seed kernel of apricot is used as edible nut and for the production of edible oil. In the present study, 147 diverse accessions of wild and cultivated apricot belonging to 28 folk cultivars were collected and characterized for fruit, stone and kernel characters. Indigenous traditional uses and importance of fruits and kernels of these folk cultivars have been recorded and described. Promising table-type cultivars identified were Margulam, Lodi, Shakarpara, Narmo and Khurmani, while drying-type cultivars were Halman, Shakarpara, Rakchey Karpo and Tachu. Cultivars Chuli and Shadi were the most common types and widely distributed with vast variability, while other cultivars had localized presence. Some of these folk cultivars have high potential for promotion as commercial cultivars of apricot in this high-altitude area basically depending upon traditional production system. Genetic resource management including collection, characterization and documentation of existing variability of apricot is of immense importance for safe conservation and commercialization of potential cultivars to enhance farmers livelihood in this fragile agroecosystem.

Socio-economic and horticultural potential of Khirni [Manilkara hexandra (Roxb.) Dubard]: a promising underutilized fruit species of India

Manilkara hexandra (Roxb.) Dubard (Khirni) is a socio-economically important fruit and nut species of tribal population of tropical deciduous forests of western and central India. Survey and collection missions were undertaken to study the extent of variability and socio-economic importance of Khirni germplasm in diversity rich areas of Rajasthan, Gujarat, Madhya Pradesh and Maharashtra. A total of 99 accessions of this important tree species were collected from surveyed regions, of which 47 diverse accessions were selected for morphological characterization showing wide range of variation in agro-morphological traits. During the survey, sizable variability in morphological characters and high socio-economic potential of Khirni was recorded. Bark, fresh fruits and extracted seeds have high nutritional and medicinal value. Tree provides substantial livelihood support to local inhabitants as collected fresh fruits from natural populations fetch good price in local markets. Besides livelihood support species, M. hexandra contributes in the nutritional security of the women and children of this area by fulfilling the need of micronutrients and vitamin A. Due to the high market demand of fresh fruits and seeds and without any organized cultivation, pressure on natural wild populations is severely building up since last several decades and therefore, the genetic variability of this species is now facing a great threat and need immediate complementary conservation efforts. Based on higher diversity index and natural population size of this species six in situ conservation sites have been suggested for dynamic conservation in western and central Indian states and 60 accessions have been successfully cryostored.

Genetic variation among Jatropha curcas L. using dominant molecular marker collected from different agro-climatic regions of India

Genetic variability and relationship among 182 accessions of Jatropha curcas collected from total 19 Indian states were analysed based on random amplified polymorphic DNA (RAPD) marker. A total of 30 primers were chosen which produced 263 bands of which 254 were polymorphic (96.82%) across the studied accessions. The polymorphic information content (PIC) was highest for the primer Oligo 905 (0.901) and the lowest was OPAD 11 (0.620) with an average of 0.791. Jaccards coefficient of similarity varied from 0.31 to 0.98 indicates the high level of genetic variation among the genotypes studied. The overall grouping pattern of clustering corresponds well with the principal component analysis (PCA), confirming patterns of genetic diversity observed among the accessions.

Genetic resources of Chironji (Buchanania lanzan Spreng.): a socio-economically important tree species of central Indian tribal population

Buchanania lanzan Spreng. (Chironji) is a socio-economically important underutilized fruit and life support species of tribal populations of north, west and central India. A survey and germplasm collection programme undertaken in the Indian states of Rajasthan, Gujarat and Madhya Pradesh observed that B. lanzan is found as natural wild in the forest, marginal lands and occasionally in farmer’s fields. A total of 72 diverse accessions of this important tree species were collected from the diversity–rich areas of India having wide range of variation in agro-morphological traits among the accessions. This species has high socio-economic value providing livelihood to tribal population of these areas and has high potential as commercial horticulture species. Fresh ripen fruits and extracted seed kernels have several nutritional and medicinal properties. Seed kernel and extracted kernel oil is used for the preparation of several Indian dishes. Traditional indigenous knowledge revealed immense importance of almost all parts of plant like roots, leaves, fruits, seeds and gum for various medicinal applications like cure for blood disorder, fever, ulcers, burning sensation of body, diarrhoea, dysentery, asthma, snakebite, etc. Due to direct harvesting of economically important parts of tree from natural habitat, genetic resources of B. lanzan are facing severe threat of extinction and need immediate conservation efforts.

Conservation of Spices and Tree Borne Oil Seed Crops

Commercially important and historically prominent spices originating from different families, with immense diversity and distribution in the World are reportedly facing threats due to various factors. Despite most of the spices being grown commercially as defined varieties, there are few spices and wild relatives of all the spices which occur in the wild and are showing decline in their population requiring conservation efforts, in situ and ex situ. In vitro conservation for clonally propagated species by slow growth methods, use of minimal media, microtuber formation, synseed technology were adopted extensively in black pepper, ginger, garlic, turmeric, cardamom, and few minor spices. In vitro cryopreservation using meristematic tissues with promising success was achieved in the above mentioned species. Seed banking at −20 °C temperature for orthodox seeded spices and at −196 °C temperature for orthodox seeds with low viability and with short life spans and for non-orthodox seeded spices is a tested technology adopted for genepool conservation in seed producing species. In Vitro Genebanks at USA, Germany, Korea and India are undertaking sizeable diversity conservation of spices. Seed propagated species of tree borne oilseeds, due to their emerging importance are being promoted for non-edible purposes especially as biofuel crops. Post harvest handling, seed storage studies and long term storage using cryobanking was attempted in four of the most important desiccation and freezing sensitive non-orthodox seeds of jatropha, pongamia, wild apricot and neem. Long term conservation of germplasm variability was achieved with good success and cryobase collection established in India.