The effect of pinching and leaf defoliation on plant root architecture and bulb characteristics in lilium

Abstract

In plants, leaves are the most important organs together with roots in terms of plant development. The effects of leaf defoliation and pinching on root architecture and bulb development were determined in lilies 'Vong' cultivar. For this purpose, leaf defoliation was determined as 0, 25%, 50%, 100%, and pinching was performed. Root length (cm), root surface area (cm²), root volume (cm³), root diameter (mm), number of tips, number of forks, and number of crossings in root architecture were measured. The effect of bulb properties was also determined in main bulb diameter (mm), bulb fresh weight (g), bulb dry weight (g), and bulbil diameter (mm). Leaf defoliation was found to affect root growth negatively. As the defoliation rate increased, the root architectural features decreased compared to the control. In contrast to leaf defoliation, the pinching application significantly increased root length (7568 cm), root surface area (9254 cm²), root volume (176 cm³), number of tips (8553), number of forks (40106), and number of crossings (7950). However, it had no effect on root diameter in two applications. In addition, while leaf defoliation decreased bulb characteristics, pinching application significantly increased bulb fresh weight (54.24 g), bulb dry weight (4.43 g), and bulb diameter (19.43 mm). It was also determined that the application that reduced the bulb fresh weight, bulb dry weight and bulb diameter the most was 100% leaf defoliation. As a result, it was found that pinching is the best method to ensure healthy root growth and bulb development, suggesting that it can be recommended for growing lilium bulbs.