Effect of different planting methods on growth, yield and quality of two sweet corn hybrids

Two field experiments were carried out at the Agricultural Experimental Farm, Faculty of Agriculture, Suez Canal University Ismailia Governorate, during the early summer season of 2013 and 2014, to investigate the effect of some planting methods on vegetative growth, yield and ear quality of two sweet corn cultivars. A randomized complete block design in a split plot arrangement with four replications was used. The sweet corn hybrid cultivars (‘Challenger’ and ‘Dynasty’) represented main plots, while planting method treatments (direct seeds under low tunnels, transplants in open field and direct seeds in open field) represented subplots. Growing sweet corn from direct seeds under low tunnels developed plants with greatest values of plant height, plant fresh weight and plant dry weight. The direct seeded planting method had more favorable influence on unhusked ear weight as well as husked weight, length and diameter than seedling rising. The application of low tunnels cover to direct seeded sweet corn plants had clearly positive effect on yield of both husked and nonhusked ears as compared with noncovered direct seeded plants. The planting treatments did not have any significant effect on ear chemical parameters, i.e the percentage of dry matter, TSS%, reducing sugars, nonreducing sugars, total sugars and starch. Conversely, the transplant treatment produced significantly the lowest weights of unhusked and husked ear with lowest diameter and length and had significantly adverse effect on ears yield as compared to the other treatments. Dynsty ’hybrid  showed significantly higher values of plant fresh and dry weight and higher percentages of total and non-reducing sugars in sweet corn kernels than ‘Chalenger’, while kernels of ‘Dynsty’ contained higher percentage of starch than those of ‘Chalenger’. Meanwhile, no significant differences were detected between the two sweet corn hybrids in the other characters, i.e., morphological characters of the plants (plant height, number of leaves and stem diameter), all ears morphological characters (husked and unhusked ear weight, length and diameter of ears), yield of both husked ears, and chemical characters of kernels (percentage of dry matter, TSS, reducing sugars, non-reducing sugars).