Evaluation of the effects of exogenous auxin and cytokinin hormones on growth, morphology, photosynthetic pigment content and the possibility of creating favorable responses in the ornamental plant Adenium obesum

Aryan Sateei ¹ (Department of Biology, Faculty of Science, Islamic Azad University, Branch Gorgan.)
Masomeh Habibi ² (دانشکده علوم پایه، واحد گرگان ، دانشگاه آزاد اسلامی، گرگان، ایران)
Mehdi Ebadi ³ (دانشکده علوم پایه، واحد گرگان ، دانشگاه آزاد اسلامی، گرگان، ایران)
Shadman Shikravi ⁴ (دانشکده علوم پایه، واحد گرگان ، دانشگاه آزاد اسلامی، گرگان، ایران)
Mazeyar Ahmadi golsefidi ⁵ (دانشکده علوم پایه، واحد گرگان ، دانشگاه آزاد اسلامی، گرگان، ایران)

Submited date : 2021-10-07 accepted date : 2022-01-09

Keywords: development, Indole Butyric Acid, Chlorophyll, Carotenoid, Indole Acetic Acid, Kinetin, Benzylaminopurine, Adenium,

Abstract :

This study evaluates the effects of foliar application of auxins and cytokinins hormones on growth and photosynthetic pigment content in Adenium obsum. Experiments were performed in a completely randomized blocks with 8 treatments and a control group, 4 replications, and 8 stages of hormone application. Two types of auxin, IAA and IBA, 200 mg / l and of cytokinin, BAP and KIN, 400 mg / lit were used independently and in combination. The evaluated traits included leaf area, number of lateral buds and flowers, shoots and roots fresh and dry weight, chlorophyll a and b and carotenoids content. Different treatments containing BAP as well as KIN and IAA + KIN increased leaf area. Highest increase was related to IAA + BAP. The application of hormonal treatments did not have a significant effect on shoot length, except for IBA and IBA + BAP treatments but other treatments increased root length. IBA + BAP and especially IAA + BAP treatment caused a significant increase in the number of lateral buds. Stem fresh weight also increased significantly in IBA + BAP, IAA + BAP and IAA treatments, but stem dry weight increased only in IAA + BAP. The treatments had no effect on root fresh weight but its dry weight increased in all treatments except IAA and IBA + KIN.The highest number of flowers was obtained without significant difference with the control in IBA + KIN treatment. Independent or combined BAP treatments reduced the number of flowers. The content of chlorophylls a and b increased under IAA + BAP and KIN-treated treatments. IBA + BAP also increased chlorophyll b content. Carotenoid content was not affected by treatments. Morphologically, IAA + BAP clearly affected the shape of the leaves, the appearance of the veins and the general shape of the plant.