Rooted liners of the crape myrtle cultivars `Pink Lace', `Natchez' and `Basham's Party Pink' (`BPP') were grown in 20-L containers filled with a 2 peat: 1 pine bark: 1 sand (v/v) medium and irrigated for 15 weeks with irrigation water containing 0, 3, 6, 12, and 24 mm NaCl. Cultivar selection and salinity significantly affected plant growth and quality. Regardless of salinity level, `Natchez' plants had higher leaf area, total and shoot (top) dry weights and growth indices, whereas `Pink Lace' had the lowest. `BPP' had the highest average root dry weights across salt treatments. The vigorous shoot (top) growth of `Natchez' was also evident with an average shoot to root ratio of 4.1, compared to 2.7 and 2.4 for `BPP' and Pink Lace', respectively. Salinity significantly decreased plant growth and quality in the three cultivars, but the rate at which these parameters were reduced with increases in salinity differed among the cultivars. The rate of reduction in plant growth parameters was lower in `Pink Lace' plants compared to `Natchez' and `BPP'. However, foliage burn symptoms due to salt stress increased at significantly higher rate for `Pink Lace' plants compared to the other two cultivars. `BPP' plants had in general the lowest salt burn ratings at each salinity level. Leaf concentrations of Na and Cl increased with salt stress in all cultivars, but significantly lower concentrations were found in `BPP' plants. `Pink Lace' plants had better correlations with the recorded salt burn symptoms as compared to the other two cultivars.
If the inline PDF is not rendering correctly, you can download the PDF file here.