Evaluation of some promising sugarcane genotypes for different levels of nitrogen fertilization by multivariate analysis

Abstract

The present experiment was conducted at El-Mattana Agriculture Research Station in Luxor Governorate, Egypt (latitude and longitude of 25.25°N and 32.31°E, respectively) to evaluate seven promising sugarcane genotypes compared with the commercial G.T.54-9 variety based on GGE biplot and to study the association among characters using the Biplot-Principal component analysis (PCA) under different levels of nitrogen fertilizer. Two plant cane crops were planted in 2021/2022 and 2022/2023 seasons. The results showed that increasing nitrogen levels had a significant effect on the number of millable canes/fed in both seasons. Among the tested genotypes, G.2004-27 and G.2005-47 consistently outperformed the other ones in terms of stalk weight, cane and sugar yields when they were fertilized with 250 kg N/fed in both seasons. Furthermore, G.2003-47 genotype recorded higher values of brix, sucrose, and sugar recovery percentages compared to other genotypes, indicating its genetic potential for high-quality sugarcane. The GGE-biplot technique indicated that the PC1, PC2 could explain 96.6% of total genotype × environment interactions (GEI) variation for cane yield, and explains 93.98% of total GEI variation for sugar yield. The analysis also identified two mega-environments for cane yield and three mega-environments for sugar yield. Correlation analysis showed a positive relationship between cane yield and millable cane weight, as well as between cane yield and sugar yield. Additionally, sugar yield exhibited a strong positive correlation with juice purity, sugar recovery, sucrose, and brix percentages. Conversely, the number of millable canes and the percentages of brix and sucrose were negatively correlated. These findings suggest that increasing cane yield and millable cane weight can contribute to higher sugar yield. Moreover, improving juice purity percentage can enhance sugar production efficiency. Based on the principal component analysis, it was found that planting G.2004-27 and G.2005-47 genotypes, fertilized with 250 kg N/fed produced the highest cane yield and millable cane weight. Supplying G.2004-27, G.2005-47, and G.T. 54-9 with 250 kg N/fed showed the highest performance., Growing G.2003-47 applied with 210 kg N/fed recorded the best values of brix%, sucrose%, and sugar recovery%. Additionally, G.99-80, G.2009-11 and G.2003-47 given 250 kg N/fed recorded the highest number of millable canes/fed. These results provide valuable insights for optimizing crop management practices and improving sugar production.