**Abstract**

With the increase in risk of extinction of various plants, the trend has been shifted to employment of many biotechnological techniques for preservation of genetic resources of plant and is the area of research which needs to be revolutionized after a specific time period because it allows the production and selection of crop varieties with desirable characteristics during breeding process such as improved fuel, food and health facilities. Having an immense research in conservation of non-threatened species, there is a small collection of knowledge available for conservation of endangered ones. This chapter aims to highlight the various techniques in germplasm conservation of endangered or the species which are at extent of extinction and also the future directions in this field. In developing countries where most of agriculture depends upon food crops, the maintenance of genetic variation is of immense importance. On farm conservation provides the best example of preservation and evolution based on genetic variability which can occur ex-situ and in- situ environment in farms or gene bank. So, it presents the best option for conservation or maintenance of ecosystem and biodiversity which ensures survival of endangered species via germplasm. The most point to consider is that germplasm or genes have to be conserved instead of genotype. In situ conservation involves preservation of plant crops in the field condition in ecosystem where plant is adopted to grow in order to maintain self –sustaining process in natural ecosystem. Similarly ex-situ involve the collections of seed banks of genes collected from plant under natural conditions to produce desirable varieties or from tissue culture in laboratory also referred as in-vitro methodology. In –vitro techniques include cryopreservation which include freezing at much lower temperature than that of freezing point i.e. -196 °C in liquid nitrogen for preserving species which are near to extent of endangerment. Cold storage and storing at lower temperature provides best opportunity for protection against damage caused by rapid freezing. Germplasm exchange has become now a usual practice ensuring exchange of varieties between cultivated and wild types as for example in potatoes specie etc. DNA as well as gene or seed banks provide molecular sources for conservation at biotechnological level. The techniques of introgression and incorporation are basic approaches for germplasm conservation. So there is need to revolutionize and practice germplasm conservation for fulfilling future needs being aimed at conserving endangered or threatened species from conservation hotspots.

**Keywords:** germplasm, threatened species, gene resources, cryopreservation, introgression, incorporation, endangered species, tissue culture technique, seed bank, gene bank, gene pool, and breeding technology

#### **1. Introduction**

Conservation of plant genetics is one of the main areas which is to be refined and revolutionized again and again with knowledge. The phenomenon of conservation is helpful in the maintenance of the genetic basis being needed for breeding. This allows the production and selection of varieties with desirable characteristics in crops, which later can be used for purpose of feeding, fuel, and health sectors [1]. Germplasm is the plant's genetic resources such as tissues or cells which are being preserved for purpose of obtaining desired breeding characteristics. These resources are obtained from gene banks, plants grown in nurseries, and laboratory culture. The collection of germplasm usually ranges from wild species to genes which are supposed to capture traits of plants as a result of natural selection [2].

A germ is defined as the collection of genetic resources for an organism. In the case of plants, the germplasm is stored or preserved in form of seeds or trees in the nursery. So, it is the living tissue from which new varieties of plants can be grown i.e., it can be the seed from which the whole plant can be grown because it contains all the genetic makeup or information required for resources of the diversity of plants. Plant germplasm is a spice of generic materials needed by breeders to develop new varieties. This includes seeds, leaves, stems, pollen, and cultured cells. So it provides the necessary raw material to develop the commercially valuable varieties of plants [3].

It is of prime importance in the maintenance of diversity in the biological system and the security of food. Conservation of plant resources is of great importance because most of the plant species are getting endangered with time. Genetic resources are a potential sustainable source of agricultural products i.e. efficient production of crops used as food, for the reduction of poverty and maintenance of economic conditions of the population [4]. For example, in countries like Nigeria, the major source of food is from crops sowed by simple farmers which maintain them by their efforts utilizing their resources. This involves the conservation of gene resources which preserve them for storage and usage systemically at both national and international levels [5]. Hence maintaining these species for purpose of variation in genetics is therefore of immense importance especially in the case of poor farmers who are participating in the agriculture of the country at much lower input conditions in marginal land [6].

On-farm conservation provides the best example of preservation as it is helpful in the maintenance of evolution responsible for genetic variability. Variations in genes are observed in both ex-situ i.e. in a natural environment and ex-situ in the form of gene banks obtained from laboratory culture. A huge collection of the most value able crop fields are being reserved in the gene bank and are placed in modern aseptic conditions in gene bank facilities. The variety includes collection from national and international worldwide programs i.e., NAGRAB, OSTROM, and IITTA. It also includes varieties obtained from plant genetic programmers in collaboration with a national action plan [7]. It has been revealed from a scientific investigation that about 3 lac plant species of higher plants exist in the world but only 1% of them are being utilized in the world today. About 80% of food is provided by only 8–10 crops ranging from wheat, rice species to millet, and rye. Most advancements in the field of agriculture in the present day world is based on a wide range of genetic resources possessing two types of values [8]. The plant genes and various genotypes are considered for many characteristics such as insect and pest resistance, bearing the conditions of drought, plant structure, function, and color acting as an immediate source of plant genotype conservation for desired properties. Secondly, diversity in genes or genetics ensures future requirements. Hence in turn contribute to the farming system at both local or small level and national levels [9].

#### *Germplasm Conservation DOI: http://dx.doi.org/10.5772/intechopen.96184*

Moreover, variations in genetics have also resulted in losing information in an already present generation which makes the preservation of these genes much important. Because if genes for variations are not preserved, it would lead to endangerment of plant species. International board [7] as a bank for further next generations [10]. The conservation involves

