7.3.1 Production and Morphological Characterization of A. comosus Leaves

First, differences were found in the amount of leaves of the plants from the first and the second crops. The first crop plants presented an average of 69 leaves, whereas the second crop plants had 105 leaves. Regarding the length of the leaves, a varia­tion of 30-130 cm was found in the first crop plants and of 30-140 cm in the second crop plants (Fig. 7.1). Distribution by leaf length showed that (1) for longitudinal classes between 50 and 100 cm, the first crop plants’ production is statistically higher than the production of the second crop plants; (2) however, the percentage of leaves in classes between 30-40 and 100-140 cm in plants of the first crop is statis­tically lower than the percentage shown by the second crop plant leaves for the same classes, and (3) classes from 20 to 30 cm and 40 to 50 cm and the 140 cm superior class did not show statistical differences in the frequencies or percentages of leaves between the plants from the first crop and from the second crop (Fig. 7.1). The dif­ferences found between the plants from both crops are similar to those mentioned by Perez et al (2011) and Aragon et al (2012)with regard to P3R5 and MD-2 varieties.

The justification these authors give is that the first crop plants are young and their leaves are not completely developed. Therefore, leaves with lengths less than 100 cm from the first crop are fewer than the leaves of the same length of the second crop. Meanwhile, the second crop plants are mature and their leaves are more devel­oped (Perez et al 2011; Aragon et al 2012), therefore concentrating in classes above 100 cm long.

Weight evaluation of the different parts of the A. comosus plant (Table 7.2) showed that the values varied for the first and second crop plants. Total plant weight, base weight, and leaf weight of the second crop plants were significantly higher than the weight of plant parts of the first crop (Table 7.2). However, a great similarity between both crops was found in the evaluation of the distribution of the weight

Fig. 7.2 Proposed scrapping machine model for A. comosus leaves from the first and the second crops from two different plantations. (a) General dimensions (b) structural parts (c) Drum dimen­sions and part and (d) Motor and broadcast of force percentages of the different parts of the pineapple plants; the weight of the bases of the plants did not exceed 28 % of the total plant weight (Table 7.2), while the leaves presented the highest weight (over 70 % of the total weight), which makes evident leaf dominance in A. comosus morphology. These percentages coincide with those reported by Perez et al. (2011) for the P3R5 variety and D’Eeckenbrugge et al.

(2011) and Aragon et al (2012) for the MD-2 variety. They determined that the weight of the base of the plant (stalk) is not above 30 % of the total plant weight. As for most Bromeliaceaes, A. comosus’s growth depends on the development of the small stalk and abundant rose-shaped leaves to satisfy photosynthesis require­ments, necessary for fruit production (Bartholomew et al 2003).