Phenotypic characterization of indigenous rice (Oryza sativa L.) germplasm collected from the state of Nagaland, India

Abstract

Nagaland is one of the eight states in the north-eastern region of India, where a considerable diversity exists in cultivated rice. Recent exploration in this tribal-dominated state has resulted in a collection of 130 rice accessions growing under diverse agroecological conditions. The agromorphological characterization data of 124 rice landraces revealed a significant variability in plant architecture and grain morphological and quality traits. Multivariate analyses including principal component analysis (PCA) and cluster analysis were performed to assess the patterns of morphological variation. The PCA extracted 12 components, which explained 75.4% of the total variation for 38 quantitative and qualitative traits. The cluster analysis grouped 124 rice landraces into five clusters, and the number of landraces in each cluster ranged from 1 to 59. The correlations among the traits are discussed, which will be useful in considering traits for genetic improvement in grain yield and quality. The landraces have been conserved in the national genebank for further utilization.

Genetic diversity and structure in hill rice (Oryza sativa L.) landraces from the North-Eastern Himalayas of India

“…The grouping of hill rice accessions in both PCA and Ward’s cluster did not follow geographical origin for a genotype. Similar trend was also recorded in previous studies [ 47 , 49 ]. The average number of panicles per plant in hill rice accessions of Arunachal Pradesh (5.30) is lower than those reported in rice landraces from Nagaland state (7.9) [ 47 ] and rice cultivars adapted to high-altitude environments in Nepal (8.0) [ 48 ].…”

“…Similar trend was also recorded in previous studies [ 47 , 49 ]. The average number of panicles per plant in hill rice accessions of Arunachal Pradesh (5.30) is lower than those reported in rice landraces from Nagaland state (7.9) [ 47 ] and rice cultivars adapted to high-altitude environments in Nepal (8.0) [ 48 ]. Extremely strong selection pressure for adaptation to the harsh high-altitude environments and direct seeding method of planting could have limited the number of productive tillers in hill rice germplasm.…”

“…In both PCA and cluster analysis, we found that the accessions with similar names formed close groups, indicating the consistency in naming the cultivars by traditional farmers. However, in a different study with 130 indigenous rice accessions from a neighbouring state (Nagaland) in NE India, we found inconsistency in naming the cultivars [ 47 ]. Similar observation was also reported in upland rices of Nepal [ 48 ].…”

Agro-Morphological Characterization and Assessment of Variability within a Germplasm of Benin Rice (Oryza sativa L.) Varieties

“…Local varieties are valuable as they possess a huge treasure of genetic material for development and improvement programs. Several researchers reported the use of agromorphological markers in the characterization and study of rice (Oryza sativa L.) germplasm diversity in China (Yawen et al, 2003), India (Roy et al, 2013), Vietnam (Nguyen et al, 2009), Nepal (Mahendra et al, 2013) and even in Africa (Semon et al, 2005;Barry et al, 2007;Nuijten et al, 2009;Sow et al, 2013). In Benin and in our knowledge, no genetic diversity study on rice is reported.…”

Genetic relatedness among indigenous rice varieties in the Eastern Himalayan region based on nucleotide sequences of the Waxy gene

“…The Eastern Himalayan region of Northeast (NE) India, which spans over 255,000 km 2 covering Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland and Tripura states (Figure 1 ) is home to a large number of indigenous rice varieties [ 1 – 3 ]. Such varieties are cultivated under diverse agro-climatic conditions and distributed over a broad geographical area ranging from flood plains and lower catchment areas of the Brahmaputra and Barak rivers to high altitude mountains of the Himalayas.…”