GROWTH, FLOWERING AND ANATOMICAL CHARACTERS OF GLADIOLUS (Gladiolus x hybridus) AS INFLUENCED BY VERNALIZATION AND YEAST TREATMENTS

The experiment was conducted in the Department of Horticulture and Landscape Design, College of Agriculture, Basrah, Iraq with the aim to study the effect of the vernalization period and active yeast on the vegetative and flowering growth of gladiolus. The experiment involved two factors, which are the vernalization period factor (without treatment, and treatment with temperatures 5 and 10°C), and the second factor included spraying with active yeast extract in three concentrations, which are 0, 3 and 7 g L-1. The results of the study indicated a significant effect of vernalization period of gladiolus corms on plant height. As the treatment of vernalization period at a temperature of 10°C recorded the highest plant height and leaf area of 70.41 cm and 584.02 cm2, respectively. The treatment with active yeast had a significant effect on plant height, as the 7 g L-1treatment, recorded the highest plant height and leaf areas were 69.34 cm and 555.22 cm2, respectively. The vernalization period treatment at 10°C, affected on the time of flowering, as the vernalization period treatment at10°C, recorded the lowest mean for the number of days required for the flowering of plants to 100.99 days, and the highest average for the duration of flowering was 21.22 days. The treatment with active yeast had a significant effect on the number of days required for the flowering of the plants, as the treatment at 7 g L-1, recorded the lowest mean for the number of days required for the flowering of plants was 102.11 and the highest average for the duration of flowering was 21.11 days. The treatment of the vernalization period at a temperature of 10°C recorded the highest percentage, specific weight and oil density, which was 0.29%, 0.366, and 0.76 mg ml-1, respectively. Also, the vernalization period treatment at10°C, recorded the highest mean of the parenchyma cells of the mesophyll tissue and the vascular bundle diameter were 8.92 and 39.56 µm respectively. The treatment with active yeast had a significant effect on the diameter of the parenchymal cells of the mesophyll tissue and vascular bundle, as the treatment of 7 g L-1, recorded the highest means were 9.19 and 40.25 µm, respectively, with a significant difference from the other treatments. As for the interaction between the vernalization period treatment at 10°C and the yeast treatment at 7 g L-1, recorded the highest means of the parenchymal cells of the mesophyll tissue and the vascular bundle diameter, were recorded10.23 and 45.23µm, respectively, with a significant difference from the other treatments.