Seleção de clones de cana-de-açúcar para toneladas de colmo por hectare e açúcar total recuperável em nove ambientes contrastantes

Abstract

The sugarcane crop (Saccharum officinarum L.) holds significant importance in the global economic sector due to the high sucrose content present in the plant, which is extracted and processed into sugar, ethanol, and other by-products. Given this, the global relevance of sugarcane becomes evident. Therefore, the objective of this study is to select superior sugarcane clones based on tons of stalks per hectare (TSH) and total recoverable sugar (TRS), aiming to analyze genotype-by-environment interactions. Data on TSH and TRS were collected during the 2024 harvest season from early-season trials harvested between May and June, and late-season trials harvested between September and October. The experimental fields are part of the Experimentation Phase (EP) of the Sugarcane Breeding Program under the Interuniversity Network for the Development of the Sugar-Energy Sector (RIDESA/UFSCar). A total of 35 35genotypes with 28 clones (G1 – G35) end seven commercial cultivars (G29 – IACSP01-553, G30 – CV7870, G31 – CTC9003, G32 – CTC9001BT, G33 – CTC9001, G34 – CTC4, and G35 – CTC4) were evaluated. The experimental design used was randomized complete blocks with three replications. Statistical analyses were performed using R software, based on linear mixed models. The REML (Restricted Maximum Likelihood) method was employed to estimate variance components, while BLUP (Best Linear Unbiased Prediction) was used to predict genetic values. From these data, a deviance analysis was conducted, and genetic parameters were estimated.A heatmap was generated based on BLUP values to facilitate the visualization of the most promising genotypes for TSH and TRS. The results indicated that TRS exhibited higher heritability, suggesting that environmental factors had little influence on this trait, making it more efficient for direct selection. In contrast, TSH was notably affected by environmental variation, which posed challenges for selection based on this trait. Clones G28 and G27 stood out for TSH, while G11, G12, and G29 showed superior performance for TRS. Notably, clone G12 demonstrated balanced performance for both traits and good stability across environments.