Brassinosteroide analogue effect on lettuce grown at different moisture levels

Abstract

Water deficit is one of the most adverse factors for plant growth and productivity. The experiments were conducted to investigate the influence of synthetic brassinolide analogue at concentrations 100 nmol L-1, 1 nmol L-1, 0.01 nmol L-1 and 0 nmol L-1 on lettuce seedling grown at two moisture levels (reduced, control). The plants were cultivated in growth chamber under day / night temperature of 20 °C/15 °C. The total quantities of irrigation water during the experiment: reduced – 28 mm; control – 39 mm. Brassinolide analogue were sprayed on the seedlings of two butter head lettuce cultivars (Mars and Maršálus) foliage at juvenile stage of growth. The plant parameters (length, fresh weight of shoots and roots) and dry matter content were measured on 21st and 28th day after sowing. Significantly higher values of the average fresh weight and length of above ground part and roots were recorded on 28th day for the cultivar Maršálus treated with brassinosteroide analogue at concentration 1 nmol L-1 in conditions with reduced irrigation. The results showed that treatment of plants at the initial stage of the development with 1 nmol L-1 solution can limit the consequences of reduced moisture conditions. Prior to use, the most effective concentration, plant parameter which is expected to be changed and sensitivity of the cultivars to the treatment, should be taken into account.