BIOREGULATORS AND BIOSTIMULANTS ON DEVELOPMENT, GROWTH AND FRUIT YIELD OF BLUEBERRY CV. BILOXI

Abstract

In Mexico, blueberry cv. Biloxi has been successfully adapted to tropical and subtropical zones due to its low-chill requirement; however, these conditions might limit the initiation of flower buds in an organized manner, so the sprouting of reproductive buds must be improved and concentrated to increase yield. An experiment was carried out with foliar application of bioregulators and biostimulants in blueberry plants cv. Biloxi under greenhouse conditions, in order to evaluate their effect on the sprouting of axillary buds, growth and yield, expecting a positive impact on such traits, since these compounds modify or stimulate development processes within the plant. Five treatments were applied using bioregulators (thidiazuron, gibberellic acid and glutamic acid) and biostimulants (Ascophyllum nodosum seaweed extract). Treatment with TDZ (25 mg L^-1) + AG3 (12.5 mg L^-1) + GLU (75 mg L^-1) increased the sprouting of buds by 46 %, plant yield by 28 %, fruit size by 13 % and individual fruit weight by 24 %, showing the effect of cytokinin and gibberellin on cell growth. Treatments with Ascophyllum nodosum algae extracts (2 mL L^-1) promoted the elongation of shoots in blueberry plants, as well as the emission of new canes. Bioregulators helped to achieve higher yield, while the application of biostimulants failed to increase yield; however, biostimulant had positive effects on cane emission, an important aspect to consider in subsequent production cycles.