**2. Breeding history**

Capsicums are believed to have originated in the Western Hemisphere and have been used as a food source since 7500 BC. They are said to have originated in South America and spread to Central America. Capsicum was brought to Europe by Christopher Columbus, and it quickly spread across Africa and Asia. The genetic inheritance of important agro-horticultural traits, mutant forms, male sterility, disease, pest resistance, and quality characteristics were all required for the purpose of early capsicum study. It has been said in a number of places that these characteristics are driven by single genes with a dominant or recessive mode of action, and that some of these characteristics are governed by quantitative trait loci. *Capsicum annuum* is by far the most significant member of the *Capsicum* family, owing to the fact that it is the species of the genus *Capsicum* that is most often economically produced. When plant breeding first started, it was based mostly on the ability of individuals to be selected, which was a time-consuming and unstructured process. Bringing the notions of Mendelian genetics and inheritance into the field of vegetable breeding was a pivotal moment in the history of the field. Currently, plant breeders are using a variety of ways to select for desirable characteristics in their crops, with the methodology chosen depending on the objectives of the breeding programme [6, 7]. The primary goals of capsicum breeders are genetic enhancement in productivity, biotic and abiotic resistance and nutraceutical compounds.

### **2.1 Contemporary objectives of Capsicum breeding**

Depending on the location, the breeding goals for capsicum, both hot and bell pepper, varies depending on the nation of culture, the purpose of cultivation, the growing conditions, the end user, and the preferences of the customers. Some countries prefer peppers that are fiery and pungent, while others prefer peppers that are sweet. The diseases that harm the crop also differ depending on the climate that prevails in the different countries. Biotic and abiotic resistance breeding, on the other hand, is one of the most important goals in the development of capsicum varieties [8]. A comprehensive depiction of the numerous pest and diseases that affect capsicum has been presented by Pohronezny [9]. The process of disease resistance breeding begins with the discovery of resistant sources, followed by a study of their genetics, and finally with the introduction of promising genotypes. It has been shown that in the case of capsicum, a significant amount of disease and pest resistance from wild species has been introduced into commercial cultivars in order to increase disease resistance. It is also necessary to assess the amount of crossability across species when developing an interspecific hybridization programme for resistance gene

### *Capsicum: Breeding Prospects and Perspectives for Higher Productivity DOI: http://dx.doi.org/10.5772/intechopen.104739*

introgression. The utilization of wild materials for the insertion of biotic resistance genes into desirable cultivars has produced significant contributions to crop improvement, most notably in terms of increased yield and quality, as well as stability in capsicum production, among other applications. Introgression efforts to introduce disease resistance genes into superior cultivars have frequently failed when disease resistance traits are under polygenic control and linked with undesirable horticultural and economic characteristics. To counteract the ongoing growth and emergence of new disease races and strains against presently existing resistant genotypes, it is vital to seek for and deploy new resistant sources on a regular basis.

The second goal for which capsicum breeders across the globe are trying is to increase yield, which will ultimately result in increased total production. In this regard, the heterosis breeding programme is becoming more important. It is preferred that more emphasis be placed on the development of F1 hybrids based on available male sterility systems, since this reduces the amount of time and work necessary for hybrid seed production. In order to make hybrids, both genetic (GMS) and cytoplasmic male sterility (CMS) systems have been used, with the cytoplasmic male sterility system being the most extensively used. The discovery of new CMS sources, the identification of their maintainers, and the diversity of CMS systems all become key goals as a result of this process. The discovery of restorers with excellent general and specific combining capacity, as well as the insertion of resistance genes into these CMS lines and restorers, should also be a priority for the generation of hybrids.

Capsicum breeding aims are also influenced by market demand and end-use usability, among other factors. This involves breeding for horticultural economic and nutritional quality traits, among other things. Fresh market breeders are looking for characteristics such as fruit color at the unripe stage, which is often green (light, medium, or dark), fruit size-length, width, and pericarp thickness. Furthermore, the amount of pungency is an important and distinct feature of capsicum breeding that should not be overlooked. Understanding consumer preferences for pungency in a given location is an extremely important aspects of the research process. Pungency, which is a major economic characteristic of capsicum, is attributable to the presence of a chemical complex of alkaloids known as capsaicinoids in the plant [10]. Capsaicin and dihydrocapsaicin are the two major capsaicinoids in capsicum, accounting for around 90% of the total capsaicinoids in most pungent varieties.

One of the most important quality attributes that capsicum breeders consider when developing commercial varieties is the amount of capsaicin present in the plant [11]. Capsanthin concentration in capsicum is estimated using the high-performance liquid chromatography (HPLC) analytical method. The capsanthin-capsorubin synthase (CCS) enzyme is found only in the *Capsicum* genus, and it is responsible for the production of two red pigments, capsanthin and capsorubin [12]. According to the USDA, red capsicum is being bred for higher capsanthin content in order to be used as a dried spice and for industrial extracts viz, paprika oleoresin, capsaicinoids, and carotenoids. The red color of chilli peppers is indicative of the presence of capsorubin and capsanthin, whereas the yellow color of chilli peppers is due to the presence of β-carotene and violaxanthin [13]. In general, the higher the ASTA color rating, the deeper the genotype's ripening red color. It has a capsanthin content of between 70 and 100 ASTA units (low), 71–100 ASTA units (medium), and 101–150 ASTA units (high). The ASTA color affects the brightness of a product, while the surface color affects the hue. As a consequence, another major aim of capsicum breeding is the development of paprika varieties that meet the great demand for nonpungent pods with a high color value for industrial uses. Dry matter content is a critical trait to

breed for in dry capsicum, since it is used to make dry powder and whole dried fruits. Additionally, these are the most often requested characters for export reasons. While a high dry-matter content in red chilli fruit is useful commercially, there is no correlation between the dry-matter content and the fruit's capsaicin concentration [14]. It is critical to have a thin pericarp for dry capsicum in order to facilitate drying. The surface of fruits with a thick pericarp gets wrinkled and their appearance becomes bland as a consequence of drying. In response to increasing industrialization, the risk of crop failure associated with climate change, and consumer demand (both domestic and international) for more nutritious and safer foods, increased emphasis is being placed on breeding genotypes with increased tolerance to high temperatures, drought, and wider adaptability.
