Abstract:
Rosa hybrida L. is an important commercial cut flower in Sri Lanka with high demand in the local as
well as the export markets. However, failure to meet expected quality standards in cut flowers is an
obstacle in expanding this profitable industry. This study aimed to assess the impact of specific
silicon treatments on enhancing the vase life and cut flower quality of two rose varieties, namely
Grand Gala (GG) and White Success (WS), in a greenhouse trial arranged in a Completely Randomized
Design (CRD) with three replications per treatment. Rose plants, two months after bud grafting and
grown in a standard growth medium of topsoil, cow dung, and sand (in a 5:4:2 ratio) were subjected
to different treatments to evaluate the effect of selected silicon treatments on their cut flower quality
and vase life. The treatments included foliar sprays of sodium silicate (Na2SiO3) at concentrations
of 0, 50, 100, and 150 ppm, and drenching with potassium silicate (K2SiO3) at concentrations of 0,
80, 150, and 200 ppm, both applied on a weekly basis for five weeks. The experiment was set up in a
Completely Randomized Design (CRD) with three experimental units per treatment. Incorporation
of rice husk ash (RHA) into growth media at establishment (0, 50, 80, and 100 ppm) and drenching
with K2SiO3 (150 ppm) significantly improved the stem length (cm), basal and apical stem diameters
(mm), bud size (mm) and full bloom size (cm), and fresh weight (g) of flower buds in both cut rose
varieties (Grand Gala and White Success) when compared to their respective controls (p<0.05). The
basal diameter (mm), bud fresh weight (g), bud (mm), and full bloom size (cm) of variety GG were
enhanced by the RHA 100 ppm treatment. The plants treated with K2SiO3 (all levels) stored a
significantly high amount of silicon in all different parts of the cut flower. In variety GG, silicon was
deposited more in the leaves, while it was highest in the flowers of variety WS. The highest vase life
of around 12 days for GG was observed in plants treated with 100 ppm of Na2SiO3 and 80 ppm of
K2SiO3. This was followed by 150 ppm of K2SiO3, which was not significantly different from the
previous two treatments, but was significantly better than all other treatments (p<0.05).Moreover,
lightness (L*) of petals significantly reduced in WS while significantly highest redness (a*) is
reported in GG cut flower petals treated with 150 ppm and 200 ppm of K2SiO3 drench (p<0.05). This
study demonstrate that silicon sources have beneficial effects on improving the floral quality
characters of the two cut rose varieties grown under greenhouse conditions. n conclusion, it can be
recommended that applying a K2SiO3 drench of 150 ppm is the most effective treatment for
enhancing the overall quality parameters in both varieties
