Response of fennel (foeniculum vulgare L.) to cytokinins and different modalities for weeds control

A field experiment was conducted on a farmer’s field in Abu Al-Jasem village, Al-Musayyib district (30 km north of Babylon), during the winter season of 2022-2023. The experiment aimed to investigate the impact of different levels of the growth regulator cytokinin and weed control methods, as well as their interaction, on the growth and yield of Fennel (local cultivar) and its medicinal compounds. The experiment followed a randomized complete block design (RCBD) with a split plot arrangement. The experiment included four concentrations of cytokinin (0, 100, 2000, 3000) mg.L-1 as the primary factor and four weed control methods (no control, manual, herbicides, black plastic) as the secondary factor. Each treatment combination was replicated three times, resulting in a total of 16 experimental units. Each experimental unit had an area of 16 m2 and was divided into four rows of equal length (3 meters). Statistical analysis was performed using the Genestat software, and the means of the studied parameters were compared using the Least Significant Difference (L.S.D) test at a significance level of 0.05. The results can be summarized as follows: The concentration S2 (2000 mg.L-1) of cytokinin exhibited superior performance compared to other concentrations in terms of plant height, number of branches, number of inflorescences, weight of 1000 seeds, and total seed yield. It produced the highest averages for these traits, measuring 85.72 cm, 7.32 branches per plant, 117.58 inflorescences per plant, 8.28 g, and 1129.89 kg/ha, respectively. Among the weed control methods, the manual treatment showed the best results for the mentioned traits, with average values of 85.48 cm, 7.26 branches per plant, 107.89 inflorescences per plant, 9.56 g, and 1336.56 kg/ha, respectively. The interaction between cytokinin concentration S2 and the manual treatment resulted in the highest averages for the studied traits. The combination (S2 X manual) showed significant improvements, with values of 109.45 cm for plant height, 8.94 branches per plant, 147.45 inflorescences per plant, 12.14 g for weight of 1000 seeds, and 1690.65 kg/ha for total seed yield, respectively.