Study the Effect of Cultivar and Disbudding on the Bulb Propagation of Lily

 Lily (Lilium spp.) is one of the most beautiful and popular ornamental bulbous plants that belongs to the Liliaceae family. Lilies (Lilium spp.) belong to one of the six more important genera of bulbous flowers, which is the fourth most famous plant in the world after Rose, Dianthus, and Chrysanthemum. The genus Lilium comprises more than 100 species, which are mainly distributed in the northern hemisphere. These species are taxonomically divided into seven sections, including Martagon, Pseudolirium, Lilium, Archelirion, Sinomartagon, Leucolirion, and Oxypetalum. It has been suggested that early removal of Lily buds should enhance Lily bulb yield. Disbudding improves the process of bulb development through its influence on the accumulation and transport of carbohydrates in Lily bulbs. In several studies, the effect of bud removal on vegetative characteristics and propagation of Lily bulbs including cut flower length, leaf area, size and weight of the bulb, number, and size of bulbs, number, and size of scales have been reported. With considering the importance of Lily bulb production in the country and the lack of current research on new Lilium hybrids, including various Oriental and OT hybrids, this study was conducted to investigate the effect of cultivar and disbudding on the vegetative characteristics of Lily flowers and its effect on production and multiplication of Lily.

 To study the effect of cultivar and disbudding on the growth and bulb production of Lily, a factorial experiment in a completely randomized design with two cultivars (the Tiber and Donato), and three disbudding items (D0= No disbudding, D1= Disbudding at the stage of bud appearance, and D3= Disbudding at the stage of 3 cm bud length) was conducted in three replications. This research was carried out in hydroponic greenhouses in Dehaghan city, Isfahan province, in an area with a longitude of 51˚, 61´ E, 31˚, 96´ N, and 2004 m mean above sea level. Temperature, humidity, and light intensity inside the greenhouse during the growing period was 15-25 ℃, 50-70 percent, and 20-30 kilolux, respectively. Evaluated characteristics included the plant height, stem diameter, number of leaves, leaf area, number of buds, bulb weight, number of the scale, scale size, number of bulblets, and propagation coefficient.

 The results showed that cultivar and disbudding (Except stem diameter) significantly affect all evaluated traits, while their interaction had a significant impact on bulb weight, bulblet number, propagation coefficient, bulb size, and scale size. In the Donato cultivar, plant height, stem diameter, leaf area, bulb weight, bulb size, scale size, number of bulbs, and propagation coefficient were 32.9%, 6.9%, 35.3%, 40.9%, 14.2%, 70.1%, 77.9%, and 8.2%, respectively higher than Tiber cultivar, while in the Tiber cultivar, the number of leaves and number of scales was 12.5% and 54.9%, respectively higher than the Donato cultivar. The highest plant height and leaf area were observed in non-disbudding treatment. However, the shortest stem and the smallest leaf were observed in disbudding at the stage of bud appearance and disbudding at the stage of 3 cm bud length which was 10.1% and 9.4%, respectively less than the non-disbudding treatment. By disbudding at the stage of bud appearance, the maximum number of scales, the heaviest bulb, the largest bulb, and the maximum scale size was measured that increased by 11.3%, 91.2%, 23.3%, and 39.2%, respectively compared to the non-disbudding treatment, while the lowest value of mentioned traits was recorded with non-disbudding treatment. By applying bud removal treatments up to the third level, the number of leaves, the number of bulbs, and propagation coefficient increased by 2.7%, 37.0%, and 3.6%, respectively, compared to the non-disbudding treatment, although there was no statistically significant difference between disbudding at the stage of 3 cm and disbudding at the stage of bud appearance. On the other hand, the lowest value of these traits occurred in the non-disbudding treatment. In the Tiber cultivar, the highest bulb weight, bulb size, and scale size were obtained by disbudding at the stage of bud appearance, which showed an increase of 93.5%, 24.0%, and 53.9%, respectively, compared to the non-disbudding treatment. Furthermore, in the Donato cultivar, disbudding at the stage of bud appearance significantly increased bulb weight, bulb size, and scale size by 89.4%, 22.8%, and 31.5%, respectively, compared to the non-disbudding. Also, the highest bulblet number and propagation coefficient in this cultivar were obtained by disbudding at the stage of 3 cm bud length, which increased 58.3% and 0.7%, respectively compared to the non-disbudding treatment.

 In general, it can be concluded that the Donato cultivar has a significant advantage in most of the evaluated traits over the Tiber cultivar, which can be attributed to the genetic distance between different Oriental and OT hybrids. Disbudding at the stage of bud appearance, if the end of the branch is not damaged, was the most appropriate treatment for replanting, production, and propagating of Lily bulb.