The effect of date palm trees spraying with different plant growth regulators on Leaves and Fruits Plant Hormones Content, Antioxidant Enzymes status and Improvement of Production in Basra Province

Abstract

The present study has been performed at Date palm orchards located in the Shatt Al-Arab reign in middle of BasraH province during the growth season 2014-2015.date palm trees of (Hilawi and Sayer ) have been selected and sprayed with different plant growth regulators which were (50 and 100)mg/l of (auxin IAA, cytokinine BA and gibberellin GA3) at two times of application in 1/2/2014 and the second in 1/4/2014.plant hormones estimated by liquid chromatography method, as well as antioxidant enzymes status ,the percent of fruit set, natural fruit drop ,average bunch weigh and productivity of tree. Results analysis showed that plant hormones (IAA, Zeatin and GA3) level was low for each examined cultivars compared with high level of Abscisic acid in control treatment while after treatment with plant growth regulator ,all of examined plant hormones increased significantly with an exception of Abscisic acid which decreased at application level of 100 mg/l in both application times .results also showed a significant increase in examined followed antioxidant enzymes activities of Ascorbate peroxidase (APX), Superoxide dismutase (SOD), Catalase (CAT) and Peroxidase (POD) during the different growth stage of date palm fruit in control treatment , hence ,application treatment of 100 mg/l to decrease these enzymes activities. Additionally spraying treatment of date palm trees led to a significant increase of fruits set for both cultivars which were 87% and 91% for Hillawi and Sayer cultivars respectively at a concentration of 100 mg/l in both application times, also led to decrease the fruits drop to the lowest levels of 11% and 8% respectively. Date palm production was improved significantly as a consequence of plant growth regulator application times, the bunch weigh reached 6.2 kg in Hilawi cultivar and 5.1 kg in Sayer cultivar as well as the yield averages were 37.2 kg in Hilawi and 30.6 kg in Sayer.