Effect of growth stimulants on seed germination and morpho-physiological attributes in pungam (Pongamia pinnata)

An investigation was carried out to study the effect of growth stimulants on seed germination and morpho-physiological attributes of seedlings in pungam (Pongamia pinnata). The growth regulators and chemicals used in this study were IAA (indole-3-acetic acid) (100 ppm), IBA (indole-3-butyric acid) (100 ppm), GA3 (gibberellic acid) (100 ppm), KN (kinetin) (100 ppm), NAA (α-napthalene acetic acid) (100 ppm), ethrel (100 ppm), KCI (1%), KNO3 (1%), ZnSO4 (1%), KH2PO4 (1%), FeSO4 (1%) and MgSO4 (1%). The seeds were soaked in the respective solutions for 12 h. Water-soaked seeds served as control. Seeds soaked in IBA (100 ppm) gave high germination. IBA also enhanced the root length. GA3 (100 ppm) enhanced the shoot length, total leaf area, total dry weight and total chlorophyll content more than other treatments. The values for most of the above parameters recorded for IBA (100 ppm) were comparable with those of GA3 (100 ppm). KH2PO4 (1%) induced a greater soluble protein content than the water-soaked seeds and other growth promoting chemicals.