**9. Conclusion**

Primitive maize cultivars in the Northeastern Himalayas of India have generated interest among researchers for their high prolificacy (4 to 8 ears/plant) and their link to the origin and evolution of maize [31]. Sachan and Sarkar [14] concluded that Sikkim Primitive maize is equivalent to pre-Chapalote, pre-Nal-Tel, and prehistoric wild corn of Mangelsdorf. Besides being of interest for origin and evolution, Sikkim Primitives serve as a valuable source of prolificacy, pest resistance, and drought tolerance, given their resilience against natural challenges.

To enhance farm productivity and food security in the rainfed Eastern Himalayan region, it is necessary to intensify the existing maize-fallow system by incorporating more crops per unit area. This requires careful crop selection and increased productivity, especially in rainfed ecosystems. However, intensified production systems also demand higher energy and other inputs. Therefore, focusing on sequential cropping in mono-cropped areas and crop intensification is crucial for improved agricultural production. Vertical growth, by increasing productivity per unit of land, offers an alternative to expanding horizontally due to limited space.

Genetic characterization and improvement of local and indigenous maize cultivars are pivotal in addressing their limitations. In Sikkim, the rapid introduction of high-yielding and hybrid varieties has led to the decline of traditional landraces in agroecosystems. Thus, conserving these landraces in the National Bureau of Plant Genetic Resources (Indian Council of Agricultural Research) is imperative for future research, registration, and protection under the Protection of Plant Varieties and Farmers' Rights Act 2001.

#### *Exploring the Diversity of Maize (*Zea mays *L.) in the Khangchendzonga Landscapes… DOI: http://dx.doi.org/10.5772/intechopen.112566*

Diversification and intensification of maize-based systems, through traditional crop management practices, can enhance profitability and resource use efficiency in both irrigated and rainfed ecosystems of the Sikkim Himalayas. Diversifying monocropped maize areas improves the profitability and productivity of organic agriculture, sustaining the livelihood security of organic growers in Sikkim. This approach supports the development of a more sustainable agricultural system, contributing to food security and livelihood enhancement.

The Eastern Himalayan region of India is widely recognized as a significant secondary centre of maize diversity, housing a diverse array of genetic resources. Maize cultivation in this region spans altitudes from 300 to 2500 masl. A field investigation conducted between 2010 and 2022 employed a combination of traditional knowledge and scientific methods to characterize maize morphologically. A comprehensive literature review documented the diversity of maize cultivation in the Sikkim Himalaya since the 1960s. The primary objective was to assess the number of indigenous maize varieties cultivated in the Sikkim Himalayan region approximately 60 years ago until 2023.

Categorizing maize landraces provides valuable insights into the diversity and classification of maize varieties, contributing to our understanding of maize genetic resources. The study also involved the collection of *in situ* germplasm in farmers' fields to conserve cultivated plant diversity. Prioritization at the species level and in specific geographic regions was necessary due to the dynamic demand for germplasm. The primary objective was to assess the risk of extinction or erosion of specific maize germplasm, crucial for cultural and ecological preservation. The study aimed to safeguard valuable genetic resources, ensuring their availability for food security, livelihoods, climate resilience, and research. Furthermore, the study focused on improving landraces and increasing access to high-quality germplasm.

During the study, as many as 31 different landraces of maize were identified, highlighting the need for comprehensive research on the genetic characterization of each variety, which remains unexplored in the region. Notably, *Murali Makai, Seti Makai, Pahenli Makai, Rato Makai, Baiguney Makai, Gadbadey Makai, Tempo-Rinzing*, and *Lachung Makai* exhibited excellent adaptation to local environments ranging from 300 to 2500 m. These landraces displayed variations in agronomic and quality traits, as well as resistance to biotic and abiotic stresses. Their adaptability has resulted from natural and artificial selection. Conserving these landraces is crucial for future food security and sustainable agricultural practices.

Genetic research on Himalayan maize is critical for unraveling the genetic basis of unique traits, including agroclimatic adaptability, disease and pest resistance, and abiotic stress tolerance. This knowledge is essential for breeding superior maize varieties with enhanced productivity, nutritional value, and resilience. Additionally, studying the genetic diversity of Himalayan maize aids in conserving valuable landraces and heirloom varieties, which possess traits absent in commercial cultivars, thus ensuring long-term food security and farming community resilience. Genetic research facilitates the identification and utilization of genes and markers associated with desirable traits, enabling the development of molecular breeding techniques like marker-assisted selection and genetic engineering for targeted maize improvement. Furthermore, understanding the genetic diversity and population structure sheds light on maize's evolutionary history, migration patterns, and contributes to broader scientific knowledge of crop domestication and genetic dynamics. This research supports the formulation of sustainable agricultural policies and strategies by providing evidence-based data on crop improvement, seed systems, biodiversity conservation, and farmer rights. Ultimately, the genetic research on Himalayan maize is pivotal for

advancing our understanding of unique traits, conserving genetic resources, enhancing breeding programs, and fostering sustainable agricultural practices, thereby promoting food security, resilience, and the well-being of farming communities.
