## 4 Discussion  
### Canopy Architecture and Volatile Compounds  
The mean values of LAI and LAI\({}_{\rm e}\) for all trees fall within those reported by [PERSON] et al. (2013) (2.2-4.5) for different clones of cacao in Brazil. The range of the mean values of canopy cover found in the present study was between 67% and 94%, which is similar to the range (72%-91%) obtained by [PERSON] et al. (2013) in Criollo and Forastero hybrids of cacao trees from Indonesia. The significant differences found between the two blocks for LAI, LAI\({}_{\rm e}\), and crown porosity may be due to the fact that Block 1 was planted in March 2013, while Block 2 was planted in October 2013, and therefore, their maturity stages were different at the time of measurements, giving an average LAI of 2.89 for Block 2, which is lower than that of Block 1 (3.35). High-resolution aerial images could be obtained using Unmanned Aerial Vehicle (UAV) platforms and high-resolution visible cameras. It is expected that by using the latter type of high-resolution images, the correlation between VitiCanopy and the aerial extraction of canopy architecture features will improve due to a more accurate gap analysis.  
All volatile compounds found in the cocoa beans have been previously reported in other studies. Ten out of 20 of these compounds provide aromas related to nuts, roasted, cocoa, and chocolate, while six compounds provide fruits aromas including banana, cherry, and pineapple. Acetoin and 2,3-butanediol, which elicit creamy and butter aromas, were also found. According to [PERSON] et al. (2013), the alcohols found in cocoa are due to fermentation and decrease with drying and roasting. However, 2-heptanol and phenylethyl alcohol, which give fruity and floral aromas, are commonly found in cacao. In the present study, phenylethyl alcohol was the most abundant compound in most of the samples. Furthermore, aldehydes and ketones, followed by esters and pyrazines, are the most important to determine cocoa quality ([PERSON] et al., 2013; [PERSON] et al., 2013), and in this study, seven compounds from aldehydes and ketones, four esters, and three pyrazines were found (Table 2). According to [PERSON] et al. (2013), phenethyl acetate is an important ester in fermented cocoa beans, and higher concentrations of this compound are an indicator of high cocoa quality. In the present study, this volatile compound was  
Figure 8: Original aerial image obtained from Google Map Pro (**A**), and plant-by-plant mapping of effective leaf area indexes (LAI\({}_{\rm e}\)) (**B**) and aroma profiles for phenethyl acetate (honey/floral/yeasty/cocoa) (**C**); 2-phenyl-2-butenal (sweet/cocoa/nutty/beany) (**D**); isoamyl acetate (banana/fruity) (**E**); pyrazine tetramethyl (roasted/cocoa/coffee/nutty/earthy) (**F**); phenylacetaldehyde (honey/rose/cocoa) (**G**); and 2,3-butanediol (cocoa butter/creamy) (**H**).  
identified in 22 out of 24 samples. On the other hand, similar to the present study, tetramethylpyrazine has been reported in other studies as the most abundant pyrazine and is one of the most important volatiles for cocoa flavor [36]. This was found in all except one sample from this study (Figure 5).