Pineapple (Ananas comosus ‘MD-2’) planting material responses to root biostimulants

The response of the pineapple (Ananas comosus ‘MD-2’) planting material root mass to the application of a single or a consortium of microbes or combination of macro and micronutrients was determined in two experiments with 10 replications of one plant per treatment grown in plastic bags. The commercial product rates were used based on a spray solution of 2000 L ha^‑1 and a density of 65000 plants ha^‑1, using 30 mL of each treatment solution per plant. The application was done directly to the young apical leaves of the crown or suckers using a 50 mL graduated syringe. The root stimulant Invigorate^® improved the dry root weight by 12% when applied on crowns one day after transplant (P=0.0125) and by 57% when applied on suckers seven and 30 days after transplant (P<0.0001). Other products that also improved the dry root weight on suckers were Timorex Gold^® (+45%), Cronox^® (+36%) and Rhizomagic^® (+34%). Based on these results, the application of products with useful microorganism and plant extracts may have beneficial effects on pineapple root development, but future research is needed to fine tune the timing of the application to optimize the effect.