Sinapis alba growth inhibition test on waste

Author: 
Ujaczki Éva

The Sinapis alba is a sensitive test plant the growth of which is inhibeted in the presence of toxic substances. Based on the measurement of the root and shoot length the toxic effect can be calculated. 

The Sinapis alba (white mustard) root and shoot growth inhibition test can be carried out according to Gruiz et al. (2001), which is a modified version of the Hungarian Standard 21976-17:1993 (Seedling plant test for waste) test to direct contact with soil. 20 Sinapis alba seeds are placed onto 5 g dry powdered soil in a Petri-dish, wetted with 3.5 ml water and incubated at 20 °C for 3 days in darkness. Two replicates are applied in all cases. For the determination of the inhibition percentage the lengths of roots and shoots is measured manually, then according to the following formula the inhibition percentage values are calculated:

H(%) = (K - M)/K * 100, where H: inhibition percentage [%]; K: length of roots/shoots in case of the uncontaminated control (tap water on a filter paper) [mm]; M: length of roots/shoots in case of polluted samples [mm].

Source: 

Gruiz K., Horváth B., Molnár M.: Environmental toxicology, Műegyetemi kiadó, Budapest, 2001.