Response of two broccoli varietys Brassica oleracea Var. italica to seaweed extract Stimax nature and dried baker's yeast.

Abstract

The experiment was conducted at the Research Station of the College of Agriculture and Marshlands/University of Thi Qar during the 2024-2025 agricultural season with the aim of studying the response of two broccoli varieties (Brassica oleracea Var. italica) to the seaweed extract Stimax nature and dry baker's yeast. The study included three factors: the first factor was two broccoli varieties, Jasmin and Sidra; the second factor was three concentrations of the seaweed extract Stimax nature (0, 1.5, and 3) ml L^-1, and the third factor was three concentrations of dry baker's yeast (0, 3, and 6) g L^-1. Thus, the experiment included eighteen treatments with three replicates for each and a number of experimental units of (54). It was implemented as a factorial experiment using split-split plots twice within Randomized Complete Block Design (Split-Split plot design in RCBD). The results were statistically analyzed using the statistical program (Genstat), and the test was performed the significance of the differences between the means was determined using the least significant difference (LSD) test at a probability level of 0.05. The results showed the significant superiority of the Sidra variety in (leaf content of total chlorophyll, floral cruds content of vitamin C, and percentage of nitrogen and potassium) at averages of (69.915 and 71.789) mg 100g^-1 f. w., (1.835 and 1.499) %, respectively, no significant differences were observed in the percentage of phosphorus. The concentration of 3 ml  L^-1 of seaweed extract (Stimax) was significantly superior in (leaf content of total chlorophyll, floral cruds content of vitamin C, and percentage of nitrogen, phosphorus, and potassium) at averages of (70.252 and 69.694)  mg 100g^-1 f. w., (1.873, 0.460, and 1.548) %, respectively. The results also showed the significant effect of the concentration of 6 g L^-1 of yeast suspension dry bread in (leaf content of total chlorophyll, floral cruds content of vitamin C and percentage of each of nitrogen, phosphorus and potassium) at averages of (75.025 and 75.956) mg 100g^-1 f. w. and (2.023, 0.523 and 1.668) % respectively. The two-way interaction treatments, were significantly superior to the interaction treatment between the Sidra variety and the seaweed extract (Stimax nature) at a concentration of 3 ml L^-1 and achieved the highest averages in (leaf content of total chlorophyll, floral cruds content of vitamin C, and percentage of each of nitrogen, phosphorus, and potassium) at averages of (71.327 and 74.989) mg 100g^-1 f. w. and (1.932, 0.460 and 1.547) %, respectively. Also, the two-way interaction treatment between the Sidra variety and the dry baker’s yeast suspension at a concentration of 6 g L^-1 was significantly superior in (leaf content of total chlorophyll, floral cruds content of vitamin C, and percentage of each of nitrogen, phosphorus, and potassium) at averages of (77.317 and 81.411) mg 100g^-1 f. w. and (2.132, 0.531 and 1.672) % respectively, in addition to the significant superiority of the two-way interaction treatment between spraying with seaweed extract (Stimax nature) at a concentration of 3 ml L^-1 and dry baker’s yeast at a concentration of 6 g L^-1 in (leaf content of total chlorophyll, floral cruds content of vitamin C and percentage of each of nitrogen, phosphorus and potassium) at averages of (77.307 and 79.567) mg 100g^-1 f. w. and (2.218, 0.590 and 1.708) %, respectively. The triple interaction treatments between the Sidra variety and the seaweed extract (Stimax nature) at a concentration of 3 ml L^-1 and the dry baker's yeast suspension at a concentration of 6 g L^-1 had a significant effect and achieved the highest averages in (the content of the floral cruds of vitamin C and the percentage of each of nitrogen, phosphorus and potassium) amounting to (84.400 mg 100 g^-1 f. w.) and (2.333, 0.630 and 1.713) %, respectively, and no significant differences were observed in the content of chlorophyll in the leaves.