Growth and yield response of green gram cultivars to simulated acid rain stress

Ten day-old plants of two green gram cultivars ADT-1 and Vamban were exposed to simulated sulphuric acid rain (SAR) of pH 5.5, 4.0, 2.5 and 7.0 (as control) for 5 consecutive days to determine their effects on growth and yield. The results indicated that acid showers of pH 5.5 and 4.0 favored plant growth in both the cultivars. The photosynthetic pigments, soluble protein, reducing and total sugars and starch in both cultivars were higher at pH 5.5 and slowly decreased with increasing levels of acidity. The acid rains of pH 5.5 and 4.0 substantially increased the number of pods and seeds/plant in both cultivars. However, the acid rain of extreme acidity (pH 2.5) was found to be inhibitory. Among the two cultivars, Vamban was found to be more sensitive than ADT-1.