In vitro bulb formation of direct and indirect regeneration of Lilium orientalis cv. “Starfighter” plants

Abstract

Background: Lily is one of the most important commercial cut flower species and one of the three major bulb crops in the commercial market. The aim was to assess and establish a suitable protocol for increasing the number of Lilium bulblets and enlarge their size. Methodology: Different plant growth regulators (TDZ, 2,4-D, 2ip, and picloram) at different concentrations for direct and indirect micropropagation were used. Also, the effect of various concentrations of sucrose alone or with growth inhibitor on bulblet formation during three repeated subcultures was examined with anatomical study. Results: For direct shoot organogenesis, culturing leaf explant on MS culture medium containing TDZ (0.5 mg/l) + 2,4-D (10 mg/l) led to the highest number of shootlets after 1 month. For indirect micropropagation, MS was supplemented with 2ip (0.5 mg/l) + picloram (5 mg/l)-induced callus tissues which were differentiated to embryos then weak shoots after 3 months. For more proliferation, the highest numbers of shootlets, leaves, and bulb scales were observed on MS culture medium supplemented with 1.0 mg/l of BA plus 0.2 mg/l NAA. Using 60 g/l of sucrose plus 3 or 6 mg/l of paclobutrazol led to the highest number of bulblets/explant for the third subculture. The highest bulblet diameters were recorded with 120 g/l sucrose plus 6 or 3 mg/l paclobutrazol. Conclusion: This study had reached to optimize a suitable protocol for direct and indirect micropropagation of Lilium orientalis cv. "Starfighter" bulbs and increase the number and size of bulbs that can be beneficial for increasing the production and reduce their price. This study will help the producers for commercial purposes.

Standardization of in vitro micropropagation procedure of Oriental Lilium Hybrid Cv. ‘Ravenna’

“…Pollyanna. On MS medium augmented with 1.0 mgl −1 BA + 0.2 mgl −1 NAA, the maximum number of shoots, leaves, and bulb-scales were found ( Youssef et al, 2019 ). Cytokinin’s are well-known to inhibit elongation of terminal buds & encourage proliferation of axillary shoots when present in sufficient amounts.…”

“…Oriental Lilium of the Archelirion section is the most costly of the various lily types since their bulbs are extremely valued also their cultivation necessitates a unique procedure. They have one of the most economically valuable types of hybrid flowers that vary in height, form, colour, and other morphological characteristics ( Roh, 2011 , Younis et al, 2014 , Lucidos et al, 2017 , Youssef et al, 2019 ). The in-vitro protocol resulted in rapid large-scale production and rejuvenation of standardised disease-free planting material, recognised both as need, especially in future breeding and profit-oriented use of lily species ( Pelkonen, 2005 , Muhanmmad et al, 2013 ).…”

In Vitro Bulbification of Five Lily Varieties: An Effective Method to Produce Quality Seeds and Flowers

“…Regarding the number of scales, the results are higher than those reported by Parić et al [18], who with a treatment of 0.5 mg L −1 BAP + 0.2 mg L −1 IBA obtained microbulbs consisting of 2 scales. Meanwhile, Youssef et al [27] reported the formation of up to 8 scales per microbulb in explants grown in 1.0 mg L −1 of BAP + 0.2 mg L −1 of NAA. Regarding microbulb diameter, the results are lower than the report of researchers such as Youssef et al [27] and Akçal and Kahraman [28], as they describe microbulbs of 1.68 and 1.32 cm in diameter, respectively.…”

Propagation of Lily Arumsari using Generic Media through In Vitro Culture

“…Hasil ini dapat dibandingkan dengan penelitian Youssef et al (2019), bahwa perbanyakan in vitro dengan media MS dilengkapi zat pengatur tumbuh TDZ, 2,4-D dan picloram dengan konsentrasi yang bervariasi menghasilkan organogenesis tunas bervariasi, pembentukan kalus yang berdiferensiasi menjadi embrio hingga tunas, serta diameter umbi terbesar dengan penambahan sukrosa 120 g L -1 dan 3 atau 6 mg L -1 paclobutrazol. Media yang kaya nutrisi dan zat pengatur tumbuh tersebut tentu berdampak terhadap tunas maupun umbi lili bila dibandingkan dengan penggunaan pupuk daun.…”

“…Penambahan sukrosa 120 g L -1 pada media MS menghasilkan diameter lili oriental cv. "Starfighter" yang terbaik (Youssef et al, 2019).…”