Central University of Kerala

About: Central University of Kerala is a education organization based out in Kāsaragod, India. It is known for research contribution in the topics: Population & Catalysis. The organization has 556 authors who have published 881 publications receiving 7474 citations.

Occurrence of Life Cycle Dependent Monophasic and Biphasic Molting in a Parasitic Isopod, Mothocya renardi

Abstract: This paper reports the occurrence of life cycle dependent monophasic and biphasic molting in Mothocya renardi (Bleeker, 1857), a protandrous hermaphroditic cymothoid parasitizing the banded needle fish, Strongylura leiura. Although the molting in manca I is monophasic, the infective manca II, juvenile and adult stages including male, transitional, and female opt biphasic molting in which the posterior half of the body molts first, followed by the anterior half. The molt cycle (monophasic and biphasic) in M. renardi is broadly divided in to four sequential stages, premolt, molt, postmolt and intermolt. Five distinct premolt stages (D0-D4) were also identified through the microscopic observation of characteristic changes reflected in different appendages of manca stages and adult infective stages. Pleotelson, uropod rami and dactylus of the first pereopod and antennae were used for the identification of stages of monophasic molt cycle. By undergoing monophasic molting, the manca I was transformed into the manca II which then undergoes biphasic molt. The characteristic changes related to biphasic molting were well reflected in the maxillule. When the maxillule showed characters of the premolt stage D2, the posterior half of the body had already exuviated. Molting of the anterior half ensued within 2–3 days after posterior half ecdysis. Occurrence of a series of biphasic molts resulted in the transformation of manca II into the successive stages in the order juvenile, male, transitional and female.

SSR marker-based genetic diversity analysis and SNP haplotyping of genes associating abiotic and biotic stress tolerance, rice growth and development and yield across 93 rice landraces.

Abstract: As rice is the staple food for more than half of the world’s population, enhancing grain yield irrespective of the variable climatic conditions is indispensable. Many traditionally cultivated rice landraces are well adapted to severe environmental conditions and have high genetic diversity that could play an important role in crop improvement. The present study revealed a high level of genetic diversity among the unexploited rice landraces cultivated by the farmers of Kerala. Twelve polymorphic markers detected a total of seventy- seven alleles with an average of 6.416 alleles per locus. Polymorphic Information Content (PIC) value ranged from 0.459 to 0.809, and to differentiate the rice genotypes, RM 242 was found to be the most appropriate marker with a high value of 0.809. The current study indicated that the rice landraces are highly diverse with higher values of the adequate number of alleles, PIC, and Shannon information index. Utilizing these informative SSR markers for future molecular characterization and population genetic studies in rice landraces are advisable. Haplotypes are sets of genomic regions within a chromosome inherited together, and haplotype-based breeding is a promising strategy for designing next-generation rice varieties. Here, haplotype analysis explored 270 haplotype blocks and 775 haplotypes from all the chromosomes of landraces under study. The number of SNPs in each haplotype block ranged from two to 28. Haplotypes of genes related to biotic and abiotic stress tolerance, yield-enhancing, and growth and development in rice landraces were also elucidated in the current study. The present investigation revealed the genetic diversity of rice landraces and the haplotype analysis will open the way for genome-wide association studies, QTL identification, and marker-assisted selection in the unexplored rice landraces collected from Kerala.

Phenotypic Characterization and Genetic Diversity of Sugarcane Varieties Cultivated in Northern Karnataka of India based on Principal Component and Cluster Analyses

Abstract: Sugarcane is a major commercial crop grown in India and across the world. Hence, several elite varieties have been developed now-a-days to overcome many obstacles including abiotic stresses and diseases. The present study was undertaken to screen genetic variation among twenty four sugarcane varieties that are commonly cultivated across Northern Karnataka, India with reference to physicochemical characters. Experiment was conducted in triplicate following randomized complete block design (RCBD) at S. Nijalingappa Sugar Institute, Belagavi, Karnataka, India during February 2016-17. Physiological parameters such as internode length, stalk height, plant height, stalk girth, number of internodes, single cane weight, single cane volume of juice, cane yield and recovery were investigated. Further, statistical techniques such as principal component analysis and agglomerative hierarchical clustering were performed to characterize the twenty four varieties. Among twenty four sugarcane varieties studied, Co 86032 and CoC 671 were found to be elite varieties with respect to sugar recovery and cane yield, whereas varieties such as Co 86032 and Com 0265 were found to be best with respect to cane yield only. Based on the results obtained, eight varieties, viz., Co SNK 09232, Com 0265, Co 86032, Co SNK 09293, Co SNK 07680, CoC 671, Co 13006 and Co 2001-15 were found to be good with respect to overall qualities. Further studies need to be involved with molecular marker that would help in identification of elite varieties which could substantially contribute to construction of genetic resources library that may in turn find maximum use in molecular breeding.