Abstract

Introduction. Dragon fruit, which belongs to the cactacea family, is an exotic fruit with multiple gastronomic and nutraceutical uses, and has been consumed since pre-Columbian times. In Costa Rica its consumption is not traditional and commercial cultivation is not well known by farmers, thus it is necessary to stimulate interest as an alternative and economically profitable crop, mainly for the Chorotega and Central Pacific region. Objective. To evaluate the effect of different cladode sizes and natural solutions (biostimulants) on growth, root development and shoots. Material and methods. The experiment was conducted at the Santa Cruz Experimental Farm of the University of Costa Rica, during 2016 and 2017. Two experiments were developed; in the first, 40 cm cladodes were used under three natural solutions (green coconut water, mature coconut water, and lentil extract) at concentrations of 150, 300 and 600 ml.L^-1. In the second, cladode size between 20 and 110 cm was evaluated. All cladodes were sown for 60 days in nursery bags (2 L) and then length and width of the shoots, length and number of roots, dry and fresh weight of roots, and the allometric measurement''LxA'' were measured. Results. The solution with mature coconut water at 300 and 600 ml.L^-1showed 8 cm longer shoots than the control, while green coconut water at 300 ml.L^-1showed the highest dry and fresh root weight. Likewise, it was shown that a larger cladode size presents greater shoots. Conclusion. Cladode size of 400 cm²in LxA (> 60 cm) guarantee the best development of the asexual seed and cladodes with an area of 200 - 400 cm²(≈ 30 - 60 cm) are of medium quality.

Keywords: shoots; cuttings; hormone; allometry