The growth and nutrition of pineapple (Ananas comosus L.) plantlets under different water retention regimes and manure

Despite the many advantages of pineapple plants offered by micropropagation, there is difficulty in rooting and slowness in the growth of seedlings, requiring a long period of acclimatization in the greenhouses. The aim of this study was to evaluate organic sources and water retention polymers used for pineapple cultivar seedlings during the acclimatization phase. The experimental design was randomized blocks in a 2 × 2 × 3 factorial design. Bovine and goat manures were the organic sources that provided the greatest increases in growth characteristics for both cultivars. Goat manure was the organic sources that provided the greatest increases in growth characteristics for both cultivars. Provid seedlings with 20 leaves, height of 19.4 cm, diameter of the rosette of 26.03 mm and 23.1 cm of length of the root system at 270 days to “Vitoria”. For "Imperial" the goat manure promoted seedlings with 20 leaves and height of 27.8 cm in 220 days. Bovine manure provided greater nutritional gains to seedlings. The use of the hydrogel did not favor the growth of shoots. However, it resulted to the increase in root dry mass when incorporated into the manure for both cultivars. The "Imperial" cultivar had a higher macronutrient intake on seedlings' leaves than the "Vitoria" cultivar at 270 days of acclimatization.   Key words: Fruit production, Ananas comosus, propagation, hydrogel, organic fertilizers.