Improved regeneration and transformation protocols for three strawberry cultivars

Abstract

strawberry (Fragaria × ananassa) is an economically important soft fruit crop with polyploid genome, which makes the breeding of new cultivars difficult. simple and efficient methods for transformation and regeneration are required for cultivars improvement in strawberries. In the present study, adventitious shoot regeneration has been investigated in three cultivated strawberry plants, i.e., Festival, sweet charlie, and Florida via direct organogenesis using the in vitro juvenile leaves as explants. explants were collected after sub-culturing on a propagation medium composed of Ms supplemented with 0.5 mg/l Ba; 0.1 mg/l Ga3 and 0.1 mg/l IBa. To select the suitable organogenesis, the explants of the three cultivars were cultured on Ms medium supplemented with different concentrations of TDZ (1, 2, 3, and 4 mg/l), then incubated at a temperature of 22 °c ± 2. Medium containing 2 mg/l TDZ revealed the best regeneration efficiency with the three cultivars (72% for Festival and 73% for sweet charlie and Florida). after 4 weeks the produced shoots were cultured on Ms medium with different concentrations of Ba and Kin to enhance shoot elongation. Results showed that the medium containing 1.5 mg/l Ba and 0.5 mg/l Kin revealed highest elongation efficiency (88% and 94%) for Festival and sweet charlie, respectively. On the other hand, medium media containing 1.5 mg/l Ba and 0.1 mg/l Kin showed highest elongation efficiency (90%) in Florida. elongated shoots were successfully rooted on Ms medium containing 1.5 mg/l Naa. Furthermore, transformation of the two cultivars, Festival and sweet charlie, has been established via Agrobacterium strain LBa44404 containing the plasmid pIsV2678 with gus-intron and bar genes. Three days post-cocultivation, GUs activity was screened using the histochemical assay. The results showed 16% and 18% of the tested plant materials had changed into a blue color for Festival and sweet charlie, respectively. Out of 120 explants only 13 shoots were developed on bialaphos medium for each cultivar, representing 10.8% bialaphos-resistant strawberry shoot. The presence of both the genes bar and uid a was detected by PcR and Northern, giving a transformation efficiency of 5%.

In vitro propagation of two strawberry (Fragaria ananassa Duch.) cultivars of Bangladesh

“…But finally (at 90 DAC), BARI Strawberry-1 produced longer shoots (13.62 mm) than Modern Strawberry-5 (Festival) did (12.95 mm). Zakaria et al (2014) also found varietal differences in in vitro shoot elongation of strawberry.…”

“…At 90 DAC, the maximum number shoots (10.41) was recorded from Modern Strawberry-5 (Festival) than BARI Strawberry-1 (10.33). Zakaria et al (2014) investigated adventitious shoot regeneration in three cultivated strawberry plants, i.e., Festival, Sweet Charly and Florida via direct organogenesis using the in vitro micropropagation and revealed significant differences among cultivars. The strawberry varieties showed significant variations in shoot length throughout the culture period in vitro (Table 1).…”

Defense response enhancement in strawberry via elicitors

“…Adventitious shoots regeneration in strawberry via organogenesis has been previously reported from different explants, such as leaves (Debnath et al 2007 ; Zakaria et al 2014 ) and petioles (Debnath 2005 ).…”

“…Husaini et al ( 2008 ) developed a reliable and highly efficient somatic embryogenesis system of strawberry leaf explants on medium supplemented with TDZ at concentration of 4 mg/l. In study of Zakaria et al ( 2014 ), adventitious shoot via direct organogenesis has been regenerated in three strawberry cultivars, i.e., Festival, Sweet Charlie, and Florida using the in vitro juvenile leaves explants on MS medium supplemented with 2 mg/l TDZ.…”

Genetic control of in vitro morphogenesis in wild strawberry (Fragaria vesca)

“…The phenomenon of morphogenesis, observed in in vitro culture, as the capacity of cultured cells and/or plant tissues to regenerate into a complete plant is now widely applied in horticultural production aimed at commercial plant multiplication, including fruit species of the genus Fragaria spp. (Quiroz et al., ; Zakaria, Hussein, Abdel‐Hadi, & Abdallah, ). Many factors have a significant impact on plants’ regeneration capacity in vitro.…”