Chemical response of chrysanthemum plants to organic materials and tryptophan

A field experiment was carried out in the Horticultural Station at the department of Horticulture and Landscape, Tikrit University, during fall of 2023. The experiment studied the chemical response of chrysanthemum plants to organic materials consisting of 1:2 biochar and vermicompost (O) (0, 2, 4, or 6 %) and amino acid tryptophan (A) sprayed at levels (0, 0.25, 0.50, or 0.75 mg L-1). The results showed that there were significant effects of the two factors on the active ingredient Kaempferol. There was significant superiority of treatments T13, T14, T15 and T16 ( 6% of the mix). These treatments recorded the highest values ​​of Kaempferol ( 35.44, 35.60, 35.40 and 35.22 mg L-1 respectively). Active ingredient, apigenin was significantly superior under the treatments T13, T14, T15 and T16 which received 6% of the mix. These treatments recorded the highest values ​​(18.40, 18.22, 18.60 and 18.32 mg L-1, respectively) of this parameter. The plant height and number of branches were superior (20.08 cm, 15.75 branches) under the treatment O3 organic mix 6%. Interaction of the two factors was significantly superior in Kaempferol at the treatment T14 ( 6% organic mix with 0.25 mg tryptophan). The treatment recorded the highest value (35.60 mg. L-1). On the other hand, apigenin was significantly superior (18.60 mg. L-1 ) at treatment T15 (6% organic mix with 0. 50 mg. L-1 of tryptophan). Plant height was the significantly superior (21.75 cm) under the interaction treatment of O3A1. However, number of branches was significantly superior at the interaction treatments O3A0, O3A1, O3A2 and O3A3. They recorded 16.33, 16.33, 15.33 and 15 branch plant-1 respectively.