Protocol for Screening for Salt Tolerance in Barley and Wheat

Abstract

A simple protocol is presented that tests salt tolerance in wheat and barley seedlings. The method is based on a glasshouse, aerated hydroponics test in which salt is added to the nutrient hydroponic solution in which the seedlings are grown. A list of equipment is provided including hydroponic hardware and stock solutions. Advice is given on seed storage prior to use and pregermination treatments that promote even germination of test samples. Salt treatments commence after seedling establishment in hydroponics at the 2-3-leaf stage. Visual symptoms of salinity stress include reduced leaf area, whitish appearance of lower leaves, leaf tip death, leaf rolling and seedling death. Recommended test salt concentrations for testing wheat and barley are given along with a method of recovering selected plants. Examples of protocol used are also given. 5.1 Introduction The protocol for rice needs to be adapted for other cereals such as wheat and barley. Changes are required for germination, aeration of hydroponics and test concentration. Wheat and barley seeds do not germinate well when submerged and therefore cannot be germinated in the hydroponics platforms. Seeds are therefore pregerminated and young seedlings are transferred to hydroponics. Also, wheat and barley cannot tolerate anaerobic growing conditions, and their roots need to be aerated in hydroponics. Moreover, wheat and barley are more tolerant to salt than rice and therefore are tested at higher concentrations. 5.2 Adaptations of Rice Protocol to Wheat and Barley 5.2.1 Germination Germination of wheat and barley may be improved by pretreatment with 0.8 % sodium hypochlorite; this serves to surface sterilise the seed and promotes more