EFFECT OF SHADING AND SPRAYING POTASSIUM ON GROWTH *AND YIELD OF CUCUMBER MOHANNAD CULTIVAR

Abstract

The experiment was carried out in the field of Horticulture and landscape Dept., College of Agriculture, University of Diyala during the summer season 2015, to study the effect of the shading and potassium spraying agents on some vegetative growth parameters and yield of cucumber cultivar Mohannad. Shading levels were (% 0, % 35 and % 65) (L0, L1, L2) respectively. Four potassium levels were used (0, 4000, 4500 and 5000) mg k l-1 which were applied spraying at vegetative growth of plant which were symboled (K0, K1, K2 and K3) respectively. Results showed that shading at level 35% (L1) significantly exceeded on the dry weight of vegetative shoot, yield of the plant and the efficiency of water, while level 65% (L2) gave the highest increase in leaves area compared to 0% shading. The concentration of proline and potassium in plant leaves was higher in the control treatment without shade (L0). The results showed that fourth level of potassium (5000 mg k g-1) was superior compared to 0 level in leaves area, dry weight of vegetative shoot, yield of the plant, proline and potassium concentration in leaves and the water use efficiency increased in values (%19.79, %14.46, %72.59, %20.00, %37.63, and %72.75) respectively. The effect of the overlap between the levels of shading and potassium concentrations was significant in the dry weight of vegetative shoot, yield of the plant and the water use efficiency at the level of interference L1K3 (shading ratio of 35%, and the potassium concentration of 5000 mg k g-1) which recorded an average (79.67 g plant-1, 11.68 ton h-1, 17.27 kg mm h-1) respectively. The leaves area of the plant exceeded the level of interference L2*K3 with average (309.78cm2 ), while the level of interference L0K3 exceeded the rest of the levels of concentration of proline and Potassium concentration in leaves with average (2.37 mg g-1, and 44.99 mg k g-1).