The Effect of the Growth Stimulant Bio 20 and Thinning on the Activity of the Invertase and Cellulase Enzymes and some Chemical Characteristics of Date Palm Fruits Phoenix dactylifera L. Al-Shwaithi Cultivar

Abstract

Abstract This study was conducted during the 2023 growing season in one of the private orchards in Thi-Qar Governorate, with the aim of studying the effect of spraying fruits with concentrations of the growth stimulant Bio 20 (0, 2, and 4) ml L-1 and the percentages of fruit thinning (0, 15, and 30)%, and their interactions in the activity of invertase and cellulose enzymes and some chemical characteristics of date palm fruits, Al-Shwaithi cultivar at the rutab stage. The experiment was carried out as a factorial experiment according to a Completely Randomized Block Design with six replicates to calculate the studied characteristics. Concentrations of the growth stimulant Bio 20 were sprayed and the thinning process was carried out after (21) days of pollination and upon completion of fruit set, and at (6 sprays) between one and the other (14 days) until the fruits complete growth and begin their coloring stage. The results can be summarized as follows: The results of the study showed that spraying with the growth stimulant Bio 20 achieved a significant increase in the activity of the invertase and cellulase enzymes and most of the chemical characteristics, and the concentration (4 ml L-1) recorded the highest averages for these enzymes (12.51 and 23.50) units g-1 m-1, respectively, and total soluble solids (73.83%) and dry matter (59.74%). In addition, the concentration (4 ml L-1) recorded the lowest averages with a significant difference in the percentage of water content (40.26%). The results also showed that the thinning percentage (30%) achieved a significant increase in: The activity of invertase and cellulase enzymes reached averages of (13.72 and 25.50) units g-1 min-1, respectively, and total soluble solids (69.86%) and dry matter (59.50%), In addition, it recorded the lowest averages with a significant difference for the percentage of water content (40.50%). As for the effect of the interaction treatment between the concentration of the growth stimulant Bio 20 (4 ml L-1) and the thinning percentage (30%), it was significant in giving the highest averages of activity of the invertase and cellulase enzymes and chemical characteristics during the rutab stage.