The Effect of Spraying with Spirulina Extract and Microelements on the Growth and Yield of Cucumbers

Algae extracts are an excellent source of chemical fertilizers (NPK) and plant growth promoters such as auxins, cytokinins, betaine, gibberellins, amino acids, macronutrients, microelements, and organic matter that improve plant productivity. The investigation was performed at 2019-2020 through winter seasons, in sandy soil at Ismailia Agricultural Research Station greenhouse. To investigate the impact of numerous levels of spraying of spirulina extract (after being diluted with half its volume of water) combined with or without microelements on the vegetative development and cucumber yield (Cucumis sativus L.) of Rocket cultivar. The experiment involved 7 different treatments (control, foliar fertilization by 5 ml, 10 ml, and 15 ml of spirulina extract/L water combined with or without concentrated microelements at 2 ml/L. Spraying was performed after 2 weeks planting three times 15 days intervals. The experiment was performed with three repetitions using a complete block randomized design (CBRD), and averages were compared using the test Duncan's at 0.05 level. Spraying with 15 mL spirulina with microelements achieved the highest plant height, main branches number, number of leaves, leaf area, length fruit, fruit diameter, stems and leaves fresh weight, stems and leaves dry weight, chlorophyll content and, NPK during two seasons. While the highest yield was recorded in terms of plant yield (1.27 and 1.31 kg), the yield of the experimental plot (25.59 and 26.25 kg), the total yield per fed. (10.74 and 11.02 tons) by spraying with 5 ml of spirulina extract incorporated with microelements during the two planting seasons, respectively. The results show that higher spirulina concentrations activate plant growth, chlorophyll and NPK in the leaves, while the concentration above 5 ml spirulina reduces the resulting yield.