Effect of Treated Saline Water on Flower Yield and Quality of Roses Rosa hybrida and Carnation Dianthus caryophyllus

Abstract

The effect of three irrigation frequencies of treated saline water (salinity range 2.5-3.0 dS/m) was investigated on flower yield and quality of the First Red rose cultivar grown on three rootstocks (Rosa indica, Rosa canina, and Natal Briar) and three carnation cultivars Voyore, Diana, and Chad, in two planting media, soil and volcanic rock (tuff). Water regimes for soil experiments were irrigation to the field capacity (every two days, every three days and every four days). Tuff experiments were irrigated daily at 120%, 100%, and 80% of the evaporation readings. Significantly larger rose flower size, longer and thicker flower stems, higher number of nodes, longer internodes, and fewer blind shoots were produced by First Red rose cultivar when grown on Natal Briar rootstock combined with the three irrigation levels. The three carnation cultivars performed similarly in regard to flower yields when planted in both planting media. Generally, better flower and flower stem quality (larger flower size, length and diameter, longer and thicker flower stalk, higher number of nodes, longer internodes) were produced by the three cultivars grown in soil than in tuff using this saline water. It is recommended to grow these cut flower plants in soil rather than in tuff medium when this type of saline water is available for irrigation. However, more research is strongly recommended in the field of using low quality water for cut flower production.