Relative Sensitivity and Tolerance of some Gladiolus Cultivars to Sulphur Dioxide

Abstract

Five Gladiolus cultivars, namely ‘Aldebaran’, ‘Bright Eye’, ‘Illusion’, ‘Manisha’ and ‘Manmohan’, were exposed to 1 and 2 μg l−1 sulphur dioxide to test their relative-sensitivity tolerance to the pollutant Plants were fumigated experimentally for 2 h daily Foliar injury symptoms were observed first in ‘Manisha’ followed by ‘Aldebaran’ and ‘Illusion’ at the higher dose Photosynthetic pigments and leaf extract pH were significantly decreased, particularly in ‘Manisha’ and ‘Illusion’ Overall disturbances in the plant metabolism due to SO2 treatment led to retarded growth of plants, as evident from decreased shoot length and phytomass values The order of sensitivity of the five Gladiolus cultivars to SO2 was as follows, with the greatest first Manisha, Illusion, Aldebaran, Bright Eye, Manmohan