The effect of polyploidy on some anatomical and antioxidant characteristics of Citrus ourantifulia A

Among polyploids، triploids produce seedless fruits. Triploids are produced through combining diploid and tetraploid plants. Reduction of seeds in citrus fruits will increase the customer’s tendency. Tetraploids are the important prerequisite to create seedless triploid citrus fruits. In this research، colchicine was used to generate tetraploid lemon which is necessary for triploid production. The effect of colchicine at 0. 2، 0. 6، 1 and 1. 4 percent were examined at apical meristem of lemon seedlings. To determine the ploidy level of the plants، two methods are used including flow cytometriy، and analysis of size and density of stomata. In addition، some characteristics such as plant height، secretory sacs size and density، leaf area and thickness، spongy parenchyma thickness، as well as the level of total phenol and flavonoid among tetraploid and diploid seedling of Citrus aurantifolia have been compared. The highest ploidy level in C. aurantifolia was 48. 6 percent. Ploidy induction led to decrease the height of C. aurantifolia. Comparison of secretory sac and stomata of treated plants showed that the density of secretory sac and stomata decreased in tetraploid plants compared with diploid ones. However، in tetraploid plants the size of secretory sacs and stomata were significantly larger than diploid ones. Doubling of chromosom increased the thickness of leaves، spongy and palisade parenchyma. Increasing ploidy level had no significant effect on total phenol and flavonid content of tetraploid C. aurantifolia.