A simple method for evaluating wheat (Triticum aestivum L.) root system characteristics at an early growth stage is needed. We used a hydrogel polymer medium to visualize the growth characteristics of seminal roots. The method is straightforward, and the medium is inexpensive and can easily be adjusted to better visualize the rooting characteristics. We found that: a) the optimum preparation conditions involve the addition of distilled water at about 98°C to the hydrogel, which leads to low root penetration resistance and enough oxygen to avoid hypoxic damage; b) 97.8% of seeds germinated and the roots of all plants that germinated penetrated the hydrogel medium. c) the hydrogel medium is well suited for observing the first opposite seminal (adventitious) roots in wheat plants, making it possible to discriminate differences in growth angles among cultivars. This strategy can be used to identify deep-rooting cultivars. This method could be used for evaluation of genetic resources.
2016 Japanese Society for Root Research