Sugarcane (Saccharum officinarum L.) is an economic crop cultivated in the tropical and subtropical zones. It is the world’s major crop according to production quantity. Sugarcane crop faces all types of environmental constraints due to its long life cycle period. Among various stresses, water stress creates a major obstacle to sugarcane production. Water deficit during formative stage in sugarcane causes more deleterious effect on crop growth. Plants develop mechanism to perceive external stress signals and adapt by changing in their physiological and biochemical responses. Therefore, this experiment was undertaken to elucidate the changes occur in to physiological and biochemical parameters under water stress in ten sugarcane genotypes. The water stress was applied by water suppression during formative stage (120–150 days). The third fully expanded leaf from random plant of each biological replication was collected on 120th day (irrigated condition), 135th day and 150th day after applying water stress. The obtained results showed significant differences among physio-biochemical responses in all genotypes. Minor fluctuations in physio-biochemical observations were found to be in 15 days of water stress, whereas higher level of percent changes were to be noted in samples of 30 days water stress. A minimum reduction in RWC, MSI, SCMR value, NR activity and higher increase in proline accumulation, catalase, peroxidase activities were found to be in sugarcane genotypes Co 98014, Co 0118, CoPk 05191, Co 0238 and Co 05011. Whereas the genotype Co 89003 and CoJ 64 were more affected in both stress treatment.

Genetic variability in rice breeding programs plays a very crucial role. It provides an outstanding pool of superior alleles governing better agronomic and quality characters through association mapping. For a greater understanding of population structure, the genetic relationship among different rice lines is indispensable prior to the setting of a correlation among dynamic alleles and traits. In the present investigation, the genetic diversity and population structure of 116 rice accessions were studied to understand genetic relatedness and diversity among them using 64 polymorphic SSR markers. A genotyping assessment based on SSR markers revealed a total of 225 alleles, with an average PIC value of 0.755. The germplasm lines were classified into three distinct subgroups through population structure analysis, utilizing both model- and distance-based approaches. AMOVA analysis showed that 11% of the total variation could be attributed to differences between groups, while the remaining 89% was likely due to differences within groups. This study suggested that population structure and genetic relatedness should be considered to establish marker–trait associations for association mapping when working with the core collection of germplasm lines.