## 3 Results
### Chemodiversity and Chemophenetic Index  
All calculations of chemodiversity \(\alpha\) and \(\beta\) consider the same data matrix. For the EO obtained from different organs, it was possible to observe that the Shannon index, which assesses compound diversity (richness), showed the highest value in leaves (2.45), followed by roots (1.40), branches (1.26), and stems (0.93). Conversely, the Pielou index assesses the uniformity of the volatile mixture (evenness) and indicates how the number of compounds is distributed within it. The uniformity index provides a projection of the maximum diversity of the mixture, and once again, leaves exhibit the highest uniformity value among the relative percentage of compounds (0.62), followed by stems (0.48), branches (0.38), and roots (0.35) (Figure 5) [6; 36; 37; 38].  
Regarding ontogeny, younger plants (phase I and phase II) showed lower compound diversity (with a Shannon index of 1.12 and 1.49, respectively). Conversely, adult plants registered an increase in diversity, reaching the highest values among plants measuring phase V (2.58) and III (2.56), followed by those at IV (1.96). The Pielou index in these volatile mixtures demonstrated that the uniformity in plants with III was the highest value among the relative percentage of compounds (0.72), followed by plants in V (0.64), IV (0.49), II (0.45), and the lowest value was found in young plants of I (0.36) (Figure 5).  
Chemodiversity \(\beta\) indices are commonly used to compare spatial similarities between different specimens. However, it is possible to apply these indices by treating each organ as an independent region or \"space\" of the plant [6]. The Jaccard index indicates the proportion of shared compounds between samples relative to the total number of compounds in each plant organ. In general, samples of different organs showed low chemical similarity. Nevertheless, the highest similarity was noted between branches and leaves (Jaccard index of 31.00), as well as between roots and leaves (Jaccard index of 28.57). The Sorensen index also represents similarity between samples, assigning greater weight to the presence of compounds in the sample than to the absence data of these. The Sorensen index indicated  
Figure 5: Variation among the calculated values for the Ramos and Moreira (EI\({}_{\text{R\&M}}\)), Shannon (richness), and Pielou (evenness) indices for ontogeny and for different plant organs. The same letters mean no statistical difference (\(p>0.05\)).  
a greater resemblance between roots and leaves (44.00). However, both \(\beta\) indices showed low chemical similarity among the different organs (Table 3).  
In relation to the different ontogenic phases, the highest similarity values, both for the Jaccard index (75.00) and the Sorensen index (86.00), were found between the samples in IV and V phase. Conversely, the most dissimilar samples were those of I compared to III, with values of 3.85 for the Jaccard Index and 7.00 for Sorensen (Table 3).  
The values of the R&M index were negative for all plant organs. They ranged from \(-2.01\) in roots to \(-14.71\) for stems. This indicates that the mixtures of volatile compounds in the EO in all plant studied compartments are reduced. This can be a particularity of the plant or suggest some physiological trend. The sum of the highest N\({}_{\text{OR}}\) values was found in branches (\(-158.43\)), followed by leaves (\(-155.42\)), roots (\(-98.30\)), and stems (\(-88.35\)).  
Considering ontogeny, the R&M index ranged from 3.09 to 3.93, that is, it also presented negative values, albeit with less variation than for the different organs.