Evaluation of Genetic Variability, Phenotypic Stability and Interrelationships among the Quantitative Traits of Sugarcane under Drought Stress

Introduction: Drought is a serious abiotic stress that leads to low sugarcane productivity. The complex polyploidy and lack of heritability information for drought tolerance make breeding more difficult. Yield is a polygenic trait influenced by several phenological and physiological factors. Assessing the variability, correlation and heritability of various traits under water deficit conditions is imperative. In the present study, we measured ۱۴ traits contributing to drought resistance and yield under control (well-watered) and drought (water-stressed) conditions. Materials and Methods: Around ۱۴ quantitative traits for a large population of ۱۱۹ progenies cross BO ۹۱ x Co ۷۷۵ were evaluated. The agronomic traits, which included ۶ morphological traits, germination%, tillers, cane height, internodal length, stalk diameter, and internodes in a stalk; ۲ physiological traits, such as total chlorophyll content and chlorophyll fluorescence; and ۶ yield-contributing traits, including single cane weight (SCW), number of millable canes (NMC), cane yield, Brix%, Pol%, and commercial cane sugar (CCS)%, were measured for each clone.Results: Our multivariate analysis revealed a significant difference among the treatments, genotypes, and G × E interactions. Path analysis revealed that SCW had a positive direct effect on cane yield. Here, we suggest that the traits of tiller number, total chlorophyll content, SCW, and NMC could effectively evaluate drought-tolerant genotypes.Conclusions: This formulated study with significant findings of phenotypic stability serves as a potential parameter for breeders in selecting genotypes for arid/semiarid regions.

کلیدواژه ها:

sugarcane ، Trait ، heritability ، Genotypic and Phenotypic Correlation ، path analysis