Effects of homobrassinolide 0.1% on almond maturation, reproduction, and yield

Homobrassinolide, or HBR, is a potent, naturally occurring, plant hormone exhibiting a wide range of characteristics including enhancement of cell division, cell elongation, and increase in crop yield. Experiments were conducted in which HBR 0.1% was applied to almond cultivars to examine the effects on pollen quality and yield parameters of the edible almond seed (Prunus dulcis). Solutions of HBR were applied to the almond plants in various concentrations until the branches dripped with excess solution. The applications of HBR on nut size and fruit set demonstrated a favorable increase in fruit set where the application of 1 ppm HBR yielded the greatest increase at 21.1% when compared to the control. HBR at 5 ppm was shown to be the most effective treatment in increasing pollen tube growth when compared to other plant growth regulators (PGRs) such as gibberellic acid. Through these experiments HBR showed increases in overall plant quality and yield of the almond when used in optimal concentrations.