Barley (Hordeum vulgare L.) is an important cereal not only from the aspect of foraging and producing malt, but it is also an ideal genetic model crop of cereals, in addition to rice. In order to carry out effective protection against environmental stress impacts, there is a continuous need for the breeding of resistant crops. Modern biotechnological methods can help this breeding work effectively. The objective of our experiments was the further development of a cellular level test system which makes it possible to routinely check the role of certain genes in the case of stress treatments which can be induced under various laboratory circumstances with a stable genetic transformation background. We chose the aldo-keto reductase gene (MsALR) extracted from alfalfa which plays a role in the protection against oxidative stress in order to produce transgenic crops transmitted by Agrobacterium tumefaciens. The immunoblot analysis of the transgenic markered crops showed the success of transformation. After the determination of the transgenic copy number, a selected crop line with high expression level was examined in a transient expression test system aligned to our laboratory conditions. The proportion of the epidermal cells showing red (DsRed) fluorescence calculated at the end of the stress treatment and green (GFP) fluorescence calculated before the dehydration stress treatment on the crop transformed in a transient way with the mixture of GFP and DsRed expression plasmids, as well as the parallelly measured chlorophyll and carotinoid content showed the increased resistance of the transgenic line towards the applied stress.

Keywords: genetic transformation of barley, stress resistance, GFP/DsRed fluorescence analysis