Harnessing intra-varietal variation for agro-morphological and nutritional traits in a popular rice landrace for sustainable food security in tropical islands.

Introduction: Rice crop meets the calorie and nutritional requirements of a larger segment of the global population. Here, we report the occurrence of intra-varietal variation in a popular rice landrace C14-8 traditionally grown under the geographical isolation of the Andaman Islands. Methods: Based on grain husk color, four groups were formed, wherein the extent of intra-varietal variation was studied by employing 22 agro-morphological and biochemical traits. Results: Among the traits studied, flavonoid and anthocyanin contents and grain yield exhibited a wider spectrum of variability due to more coefficients of variation (>25%). The first five principal components (PCs) of principal components analysis explained a significant proportion of the variation (91%) and the first two PCs explained 63.3% of the total variation, with PC1 and PC2 explaining 35.44 and 27.91%, respectively. A total of 50 highly variable SSR (HvSSR) markers spanning over 12 chromosomes produced 314 alleles, which ranged from 1 to 15 alleles per marker, with an average of 6.28. Of the 314 alleles, 64 alleles were found to be rare among the C14-8 selections. While 62% of HvSSR markers exhibited polymorphism among the C14-8 population, chromosomes 2, 7, 9, and 11 harbored the most polymorphic loci. The group clustering of the selections through HvSSR markers conformed to the grouping based on grain husk coloration. Discussion: Our studies on the existence and pertinence of intra-varietal variations are expected to be of significance in the realms of evolutionary biology and sustainable food and nutritional security under the changing climate.

Tracing the genetic root of Trinket cattle: an endangered cattle population of a small isolated island of Nicobar group of islands.

Trinket cattle are the inhabitant of a small island called Trinket, which is one of the picturesque islands of Andaman. This herd is thought to be of Danish leftover during their dynasty in Nicobar archipelago. When the island was abandoned by foreign invaders, indigenes utilized the animals for the purpose of meat. As a result, the cattle became semi-feral in nature. After the Great Sumatra earthquake and tsunami of Indian Ocean in 2004, Trinket island was left abandoned by indigenes and the cattle became totally feral in nature. To trace the genetic root of the cattle, this study has been undertaken based on the sequence information of the mitochondrial D-loop and cytochrome b gene. The genomic DNA was extracted from the blood samples of the Trinket cattle and was used for amplification of mitochondrial markers, and the sequence information was generated by Sanger sequencing. The analysis of sequence information revealed that the Trinket cattle belongs to Bos indicus (I) haplotype, sub-haplotype I2. The presence of I2 sub-haplotype in Trinket cattle may be due to the expansion of this I2 haplotype towards Southeast Asian countries. This is a novel input for the formulation of breeding strategy towards conservation of eco-friendly sustainable livestock in the isolated island ecosystem.