Genetic Diversity of Phenotypic Traits in the Germplasm Resources of Guitang Series Sugarcane

Purpose To analyze the major phenotypic traits and genetic diversity of Guitang series sugarcane germplasm resources, providing a reference for enhancing the efficiency of hybrid breeding in the Guitang series of sugarcane germplasm.

Methods 21 quality traits and seven quantitative traits were investigated and determined in 164 Guitang series sugarcane germplasm, which from the field conservation of sugarcane germplasm resources in Guangxi. Diversity index, genetic variation, correlation and cluster analysis were used to analyze the genetic diversity.

Results The genetic diversity index for 21 quality traits ranged from 0.3866 to 1.9776 with an average of 0.9217, with highest for bud shape and lowest for growth crack. The coefficient of variation for seven quantitative traits ranged from 7.11% to 42.86%, with an average of 27.11%. The correlation analysis showed that: plant height and stem diameter had an extremely significantly positive correlation with weight of per stalk, cane yield, and sugar yield, respectively; weight of per stalk and effective stalk number had an extremely significantly positive correlation with cane yield and sugar yield, respectively; cane yield had an extremely significantly positive correlation with sugar yield. The cluster analysis results showed that: the 164 Guitang series sugarcane germplasm could be divided into six categories. Among them, group Ⅰ had the largest number of accessions and excellent comprehensive character; the group Ⅱ had the largest average stem diameter; each character of group Ⅲ was balanced, and the effective stem number had a slight advantage; the average plant height of group Ⅳ was the highest; the average brix of group Ⅴ was the highest; the average effective stem number of group Ⅵ was the most.

Conclusion The 164 sugarcane germplasm have great variation in quality and quantity characters and rich genetic diversity. Different groups of sugarcane germplasm have own advantages. So, the hybrid parents should be selected according to the breeding objectives in the process of sugarcane hybrid.