**4. Landraces – definition and their importance in traditional farms and breeding programs**

Widely used in the literature, the term "landrace" encompasses different concepts, variable in time and space, depending on trends prevalent in the use and conservation of genetic resources. After a period of beginning when the issue of preserving and maintaining biodiversity was prevalent, today the commercial message is clear and promotes the higher nutritional and sensorial qualities of local vegetable landraces [26]. Due to their complex nature and huge diversity landraces are extremely difficult to be characterized by an all-encompassing definition (**Figure 2**).

However, over time, different authors have tried to define landraces on the basis of the characterization of their main attributes. Kiessling [27] in 1912 defined landraces as a mixture of shapes (phenotypes) with a certain degree of external uniformity, specific composition and a high adaptability to the natural, technical and economic conditions of the region of origin [28].

An interesting definition has been proposed by Prospéri et al. [29] in 1994 which attest that a landrace represents a set of genotypes belonging to the same species,

*Landraces - Traditional Variety and Natural Breed*

Day of Food Lost and Waste".

**2.4 Seed vegetables market**

'farmers, local or primitive varieties' [14].

importance of reducing food loss, the UN declared 29 September as "International

**2.3 Ecological and organic vegetables, increasingly sought after in rich societies**

The global market share of organic foods is growing from year to year. The share of trade in organic and ecologic fruit and vegetables (out of the total trade in fresh fruit and vegetables) has increased by around 10% in some european countries with high standards of living such as; Switzerland, Sweden, Austria and Denmark. In the United States, this rate is around 9%, but there has been recorded intense growth rates in the last years. Although, income per capita appears to be a determining factor in the consumption of these products, this is not the only one. The consumer education level, supermarket policies on the category of organic vegetables, the price and availability of conventional or traditional products, cultural factors, etc. can be important vectors that influence the consumption of organic and ecologic vegetables products [5].

Vegetable quality assurance is achieved by a succession of attributes related to biological material and cultivation technologies, harvesting, conditioning, processing, storage and marketing. Seed quality is the basic appropriation that characterizes the biological material. The demand of growers for quality seeds is increasing. The world market for vegetable seeds accounts for about 11% of the total plant seed market. The estimated value of the vegetable seed market in 2017 was 8.02 billion US\$, reaching 12.6 billion US\$ by 2021, with a cumulative annual rate of 8.1 [3].

In general, plant genetic resources are defined as that part of biodiversity used to generate productivity and quality in agriculture. In addition to commercial genotypes (varieties and hybrids), the genetic resources of a cultivated species include breeding lines, genetic forms obtained by various technologies by deliberate breeding (natural or induced mutant lines, substitution and addition lines, inter-specific hybrids, etc.), wild descendants, related species and local races, also referred to as

Plant Genetic Resources (PGR's) represents an important component of the conservation of plant biodiversity and the food security of the human population [15]. PGRs are actually the expression of natural variability in plants, variability that has sustained the human species for millennia. The multitude of plant species, with all existing genotypes, are especially important for ensuring food security, but also because they represent energy sources, medicines, animal feed, fiber, ecosystem services, etc. All these aspects are essential in the context of the global challenges currently facing life on Earth, in particular due to climate change and resource shortages. In the light of this, the efficient conservation and sustainable use of the

Thus, according to The Second Report on the State of the World's Plant Genetic Resources [17], approximately 7.4 million genotypes, sources of germplasm, belong to over 16,500 species of plants are currently stored in 1750 gene banks and collec-

Vegetable genetic resources (VGR's) are the foundation on which vegetable cultivation techniques and food chains integrated with them have been developed, and the genetic diversity present in small farms and germplasm collections is

**3. Vegetable genetic resources and biodiversity preservation**

PGR's is extremely important and has never been more necessary [16].

**64**

tions around the world.

**Figure 2.** *Vegetable landraces diversity.*

that a grower in a given region, uses specific cultivation methods and carries out mass selection, more or less targeted, over several generations.

Zeven [28] said that a "landrace" is a variety with high tolerance to biotic and abiotic stressors, manifested by medium but stable productive yield, under low technological inputs conditions. Landraces have also been defined as dynamic populations of a cultivated plant of distinct historical origin and identity, with genetic variability and high adaptability to specific local conditions (soil, climate, biotic stressors) adapted to cultivation technologies specific to local farmers [30].

Vegetable landraces are considered local old varieties with distinctive characteristics resulting from archaic selection and adaptation over time to pedo-climatic conditions specific to a localized geographical region, which usually exhibit greater genetic diversity than the types subjected to the usual breeding techniques. According to the definition developed by Dwivedi et al. [24] landraces represent heterogeneous, local adaptations of some cultivated species and therefore provide genetic resources adapted to the current challenges posed by biotic and abiotic stress factors.

The analysis of these definitions attests to the existence of some common elements in the characterization of landraces in cultivated plants such as; local character, historical origin, adaptability to soil, climate and stress factors, genetic variability, harvest stability, reduced inputs, traditional farms. Landraces through their long selection process by farmers during the pre-intensive agricultural period provide a great opportunity to find appropriate combinations of genes and phenotypes tolerant to complex situations [31].

In conclusion, landraces are dynamic populations usually associated with traditional farming systems. As such, their evolution was based on both natural and farmers' selection in low-input cultivation systems [32]. During long period of cultivation, farmers greatly contributed to the diversification of vegetable crops by selecting populations with moderate yield and well adapted to the specific agroclimatic conditions of different regions. The diversity of landraces is usually lower than at their wild ancestors, but considerably higher than at modern cultivars produced by plant breeding [33]. The vegetable landraces are valuable genetic resources to identify genes for increasing yield and adaptation to abiotic stress under the current and future climate changes [34].

Compared with modern varieties, the vegetable landraces have a low presence on the market, due to their lower yields, disease sensitivity, and poorer postharvest shelf life [35]. In the last period, amid an increasing interest of the consumers for

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*Vegetable Landraces: The "Gene Banks" for Traditional Farmers and Future Breeding Programs*

both as a source of food and as a source of useful genes [36, 37].

**5. Breeding perspectives of vegetable landraces**

with high yielding performance characters [38].

food [20, 40–43].

vegetable landraces is still limited.

commercial varieties [53].

traditional and healthy products of the local growers, the landraces are reconsidered

The breeding of plants is as old as their cultivation. The first vegetable growers exploited the favourable variability of landraces of the main attributes such as productivity and high tolerance to environmental stress factors. Much later, probably after a few millennia, mankind developed new methods of breeding and multiplication, including hybridization techniques, and the peak was reached through the use of molecular tools, all of which led to the creation of modern vegetable genotypes

Therefore, an important source of genes that is increasingly used in breeding programs are landraces, old varieties adapted to the conditions of a specific pedoclimatic area [39]. Due to the stronger genetic proximity to modern varieties than their wild relatives, landraces show huge potential to improve modern genotypes by increasing stress tolerance and as sources of healthy and nutritive

Featuring by a good stress tolerance and high adaptability to different conditions, despite the lack of pathogen tolerance genes, vegetable landraces are still a reservoir of genetic diversity, in particular for certain attributes of interest, such as; tolerance to abiotic stress and high fruit quality [44]. For these reasons, studies carried out on some heterogeneous tomato populations have shown that they have been, are and will continue to represent very important genetic resources used in breeding processes [28]. The genetic profiles of landraces are clearly different from those of modern genotypes [45]. It has been observed that numerous morphoanatomical, physiological and biochemical traits record significant levels of phenotypic and genotypic diversity [46]. However, information on the variation within

The antioxidant content of the edible organs of wild vegetable species is significantly different from landraces. These compositions have been associated with the features of the organs, the geographical origin and altitude at which they are found. For example, in high-rise areas of northwestern Argentina, local tomato populations with the highest concentration of antioxidants have been identified [47].

Recovering and rendering these qualities in adapted landraces to the original communities will contribute to the sustainable maintenance of these varieties [48, 49]. For example, tomato landraces are characterized by excellent fruit quality, high content in metabolites [50], antioxidants [20, 47] and volatile organic compounds [51]. Landraces

and old varieties have a typical flavour that consumers appreciate and demand,

The vegetable landraces are particularly important because they exhibit high heterogeneity (for improvement), are adapted to biotic and abiotic stress conditions, have excellent taste qualities, thus justifying a higher recovery price than

One strategy to highlight the genetic treasure represented by the landraces is to identify the size of genetic variability for primary and secondary metabolites and to establish existing links between biochemical composition of edible products, genetic basis and consumer preferences [54]. Studies from last decade [20, 55, 56] showed that in Romania it still exists many vegetable landraces that need to be

although the availability of their seeds is increasingly low [52].

preserved and evaluated for further use in breeding programs.

*DOI: http://dx.doi.org/10.5772/intechopen.96138*

traditional and healthy products of the local growers, the landraces are reconsidered both as a source of food and as a source of useful genes [36, 37].
