Potential of Open-Pollinated Varieties (OPVs) in Chilli Crop Breeding—A Review ^†

Abstract

The research for crop improvement is a continuous process that enhances plant quality, yield, and ameliorates their adaptability to changing climatic conditions. Chilli is cultivated worldwide as a vegetable, spice, or natural colour additive and is an economically and medicinally important crop. A basic requirement for crop improvement in breeding programmes is the presence of genetic diversity within the crop. Smallholder farmers of chilli usually face challenges in acquiring commercial hybrid seeds because of their high cost and the need for annual purchases. Open-pollinated varieties (OPVs) can serve as a sustainable alternative that provides broader genetic variability, allowing adaptation to local growing conditions, and enabling farmers to save seeds for successive planting season. These characteristics make OPVs economically viable and valuable genetic resources for future chilli cultivation and breeding programmes. This review highlights the potential of OPVs in promoting sustainable chilli cultivation, enhancing genetic diversity, and supporting breeding to develop resilient and economically viable cultivars.

1. Introduction

Chilli belongs to the family Solanaceae and is a member of the genus Capsicum, which includes 30 species. Among these species, Capsicum frutescens, Capsicum pubescens, Capsicum chinense, Capsicum baccatum, and Capsicum annuum L. are cultivated worldwide. Capsicum annuum is domesticated and cultivated in both tropical and temperate zones. It is a diploid specie having 2n = 24 chromosomes [1]. Fresh chilli is cultivated worldwide, with production reported from 126 countries. South Asia is the largest producer of chilli, producing about 55% of the total world production. The three main chilli-producing countries in South Asia are India, China, and Thailand [2]. China is the largest producer of chilli followed by India and Thailand. It is an important vegetable-cum-spice crop that originated in Mexico (Central America) and is also used as a vegetable and natural colourant. It is an essential component of food and is used in different medicinal products. It reduces obesity and diabetes due to the presence of capsaicin in it. Chilli is enriched with vitamins such as A, B6, and C, along with antioxidants and nutrients such as iron, zinc, and calcium [3]. It is also helpful in improving the heart, eye, and skin functions. Besides medicinal and household uses, it is also being used in the cosmetics industry for different purposes [4].

Besides chilli’s economical and medicinal importance, most countries import both chilli fruit and seed. Small farmers cannot afford to buy imported hybrid seeds and depend on seed saved from the previous season, which results in low yield. Researchers should focus on the development and selection of OPV chilli varieties, which would be economically beneficial to farmers. Selecting appropriate OPV chilli varieties that are high-yielding and well adapted to local environmental conditions can perform better and will be profitable for farmers. OPVs can also provide a base for breeding programmes. Therefore, the objective of this review is to highlight the potential of open-pollinated varieties (OPVs) in chillies and discuss their potential in maintaining genetic diversity and supporting crop improvement.

Chilli is a diverse crop and has numerous qualitative and quantitative trait variabilities [5]. The presence of diversity within a crop is a fundamental requirement for crop improvement [6]. The extent of variability present within the crop determines the actual potential for crop improvement. Interest in agro-diversity has grown over the past few decades, and scientists have begun to rediscover diversity, especially for organic and low-input agriculture. Diversity helps in overcoming and managing issues of pests and diseases, abiotic stress, and enhances the productivity and long-term stability of chilli [7]. Open-pollinated varieties (OPVs) can serve as a fundamental source for chilli crop improvement as they exhibit various genetic diversity. These are the varieties that have been continuously selected and cultivated by farmers and have adapted well to local growing conditions [8]. OPVs have the potential to form a fundamental base for chilli crop improvement and can be utilised in chilli breeding projects for the development of improved cultivars [9].

2. Common Goals for Chilli Breeding

In chilli breeding, breeders typically target traits such as yield, disease resistance, abiotic stress resistance, colour, pungency, aroma, fruit size, and pest resistance (Figure 1). The four main objectives of chilli breeding are as follows: (a) colour, size, shape, and yield; (b) disease resistance; (c) abiotic stress resistance; and (d) quality, which is determined by the presence of bioactive compounds such as capsaicinoids, flavonoids, and vitamins [10].

3. Open-Pollinated Variety (OPV)

Open-pollinated varieties (OPVs) are cultivars developed when pollination occurs within the same cultivar or variety (self- or cross-pollination). The resulting seeds or offspring are genetically true-to-type, exhibiting traits similar to their parents (Figure 2) [11].

These varieties are landraces or local ecotypes, produced through traditional selection and recurrent cultivation. Chilli OPVs originate from farmers’ selection and have adapted to local climatic conditions over generations. The literature specifically on chilli OPVs is limited, although many locally cultivated varieties are open-pollinated. For example, landraces or local varieties of Spain are OPVs and have been maintained through local seed-saving traditions and recurrent cultivation. Many of the cultivated chilli varieties, such as Guntur Sannam, Brown Jalapeno, and Kali Mirch, are maintained as OPVs and have been grown for many years [12]. These varieties exhibit traits such as fruit size, hotness, vigour, and adaptation to the local environment across many generations. OPVs has the following advantages:

• Farmers can save true-to-type seeds across generations, enabling them to be seed self-sufficient, economical, and independent from seed companies.
• OPVs develop in situ (within the local environment), which enables them to be well suited to local climatic conditions, soil, and diseases, making them resilient varieties.
• OPVs exhibit a wide range of genetic diversity as compared to hybrids, making them better suited to changes like high temperature, drought stress, and insect pests.
• The seed of OPVs can be recycled each year, allowing farmers to save the harvest for next year’s sowing, which reduces the cost of production and creates opportunities for higher profits [13].
• OPVs that are native to certain areas have unique taste and flavour, resulting in high demand in local markets. They often contain high levels of phenolics, carotenoids, and vitamins (11).
• The promotion of local seeds (OPVs) increases diversity level and contributes towards long-term food security and sustainability [14]. The comparison of open pollinated and hybrid varieties is shown in

  Table 1. Comparison of OPV and hybrid varieties.

  Feature	OPV Chilli Varieties	F1 Hybrid Chilli Varieties
  Seed-Saving	Yes—stable across generations	No—seeds segregate, traits lost
  Genetic Uniformity	Moderate, some variation	High—uniform fruit and plant type
  Local Adaptation	Excellent—evolves with environment	Limited—bred for fixed broad environments
  Yield Potential	Good under adapted conditions	Often higher under optimal inputs
  Disease/Stress Resilience	Broader genetic diversity resilience	Often built-in resistance but narrow spectrum
  Seed Cost	Low (self-saved)	High (must be purchased new, each season)

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OPV yields may be lower or less uniform than those of hybrids, but in many contexts, especially on low-input or organic farms, they can perform very well, particularly across successive seasons [15].

3.1. Role of OPVs in Biodiversity Conservation

For the preservation of biodiversity present within OPV cultivars, researchers are trying to establish seed banks that will preserve indigenous local OPV varieties [16,17]. The variability within OPVs strengthens their ability to survive under harsh environmental conditions such as drought, heat stress, irregular rainfall, pests, and diseases, which makes them valuable for local cultivation. The contribution of chillies open pollinated varieties are mentioned in

Table 2. Key aspects and contributions of open-pollinated varieties (OPVs) to sustainable agriculture.

Aspect	OPV Contribution
Biodiversity Conservation	Maintains genetic diversity; adapted to local conditions; preserved via seed banks and farmer networks.
Climate Resilience	Broad genetic pool increases stress tolerance; dynamic “ultra-cross” populations; long-term system resilience through diversification.
Agro-ecological/Organic Support	Meets organic seed standards; enables participatory breeding; thrives under low-input, biodiversity-rich systems.
Seed Sovereignty and Farmer Empowerment	Encourages local seed-saving, exchange, and innovation; reduces dependency on commercial hybrids and proprietary seed systems.
Economic Sustainability	Provides affordable seed options for smallholders; ensures stable yields across variable seasons; reduces input costs due to inherent adaptability.
Genetic Resource for Breeding	Acts as a source of diverse alleles for developing new varieties and hybrids; valuable for pre-breeding and adaptation studies.
Socio-cultural Significance	Preserves traditional varieties and associated cultural heritage; fosters farmer identity and community-based innovation in seed systems.

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3.2. Role of OPVs in Chilli Crop Breeding

Open-pollinated varieties (OPVs) continue to play a crucial role in chilli crop breeding, even after the development of hybrids. These varieties have been conserved by natural pollination and are purified through the process of repeated selection by farmers. Open-pollinated varieties (OPVs) are genetically diverse, having variable traits of interest, which make them appropriate for farmer adaptation, crop genetic improvement, and sustainable chilli production.

The main contribution of open-pollinated varieties (OPVs) in chilli crop breeding is the availability of variable traits (alleles) within its genome. OPVs, unlike highly uniform hybrids, are genetically variant and have conserved variants of alleles within their genome, providing a pool of genetic diversity for breeding that results in the development of resistant and high-yielding varieties [18]. OPVs have the potential to conserve their identity and level of diversity within their genome, making them an important asset for farmers and breeders, as these varieties are well adapted to specific local conditions and have good production [19].

OPVs are resistant to many diseases due to the presence of resistance genes in their genome, such as Phytophthora capsici, leaf spot, and other viral pathogens. Resistance to Phytophthora capsici is multi-genic and develops in diverse landrace populations, which can be used to develop improved OPVs as a donor parent in chilli breeding projects. The genome of these diverse landraces also contain other important recessive genes that are key factors for the development of elite chilli cultivars [20].

OPVs are heterogeneous in nature and conserve a wide range of intra-population variability, which enables them to adapt to adverse climatic conditions and different environments compared to hybrids. On-farm selection and repeated cultivation of OPVs by farmers allow them to gradually adapt to local environmental conditions, such as heat stress, irregular rainfall, drought, diseases, and insect pests [21].

OPVs also play an important function as breeding platforms:

• They can be improved through repeated selection and cultivation for yield, fruit quality, and stress resistance.
• The two breeding approaches such as participatory and evolutionary breeding enable farmers to co-select traits of importance, aligning breeding outcomes with local demands [22].
• Selected OPVs can act as a base for hybrid development by contributing resistance genes and quality traits to heterotic pools.

4. Concluding Remarks and Prospects

OPVs can act as a vital component of chilli breeding and production, especially in smallholder systems that require seed sovereignty, adaptability, and affordability. OPVs can replace hybrids if selection is performed properly, and with the help of modern tools and participatory approaches, their performance and resistance can be exponentially increased. Strengthening seed systems, investing in OPV improvement, and promoting farmer involvement will unlock OPVs’ potential to contribute to food security, biodiversity, and climate resilience in chilli production systems.