تأثير الرش بمستخلص الطحالب البحرية وسماد NPK المتعادل في النمو والحاصل وبعض المركبات الفعالة طبياً لنبات الكجرات .Hibicsus sabdariffa L

Effect of Spraying with Seaweed Extract and Balanced NPK Fertilizer in Growth, Yield, and Some Medicinally Active Compounds of Hibiscus Sabdariffa L.

Abstract:
This study was conducted out in one of the agricultural fields designated for the College of Agriculture / University of Karbala and affiliated with Ibn Al-Bitar Vocational Preparatory School located in Al-Husseiniyah District – Karbala Governorate during the 2023 agricultural season, to study the response of the Roselle Hibicsus sabdariffa L. For different concentrations of seaweed extract and neutral fertilizer (NPK) and their reflection in some characteristics of vegetative growth and yield and its medically effective compounds, the experiment included two factors: the first: four concentrations of seaweed extract (0, 0.25, 0.5, 0.75) ml L-1, and the second factor: It included three concentrations of NPK neutral fertilizer (0, 2.5, 5) ml L-1, and the two workers were added by spraying on the shoots.
The results showed that spraying with seaweed extract at a concentration of 0.75 ml L-1 was significantly superior in all traits terms of vegetative growth, yield, and medically active substances in Roselle plants compared to other spraying treatments, by giving it the best results for the following traits: plant height, number of main branches, number of flowering branches, number of leaves, leaf area, chlorophyll percentage, fresh weight of vegetative parts, and dry weight of vegetative parts. The same concentration also excelled in the number of calyces, fresh weight of calyces, dry weight of calyces, total yield of calyces, fresh weight of calyx leaves, dry weight of calyx leaves, and total yield of calyx leaves. Additionally, the same concentration gave the highest levels of nutrients in Roselle plants (nitrogen, phosphorus, and potassium) and the content of medically active substances in the calyx leaves (Vitamin C, Anthocyanin, Quercetin, Hibiscetin, Gossypetine, Protocatechuric acid, and Sabdaretine). Spraying with balanced fertilizer at a concentration of 5 ml L-1 was also significantly superior in all indicators.
Regarding the interaction between the study factors, the interaction treatment of spraying 0.75 ml L-1 of seaweed extract with the treatment of spraying 5 ml L-1 of balanced fertilizer (A3F2) was superior, giving the highest averages for all studied traits and mentioned above.