The 2012 ASHS Annual Conference

Research was conducted in southwestern Puerto Rico to determine the effects of two biostimulants on fruit retention and size of 'Villa Flor' mango. The biostimulants  evaluated were an agricultural formulation of blended amino acids fortified with potassium (AminoQuelant-K^TM), and an extract of the alga Ascophyllum nodosum (Stimplex^TM) for agricultural use. The alga extract and the amino acid blend were sprayed separately on the mango leaves until run-off, using the rates of 0 (control), 1, and 2 L/ha per application. The biostimulants were first applied at flowering, and applications were repeated 3 and 6 weeks later. The treatments were established in a complete randomized block design with 5 replications. Inflorescences were selected, tagged, and evaluated for fruit retention every two weeks until fruit harvest, when fruit number, size, and weight were determined. Both rates of the two biostimulants significantly increased fruit retention as compared to control plants. The trees treated with the amino acid blend had the highest fruit numbers. However, increasing fruit retention resulted in reduced fruit size and weight, regardless of the biostimulant and rate used. Because fruit size usually is an important attribute for marketing, further research is needed to determine if other application times and rates of these or other biostimulants may be used to attain increased fruit retention without reducing fruit size.