Division of Plant Physiology, Indian Agricultural Research Institute, New Delhi 110 012, India
*Corresponding author; E-mail: sp_sidhu@yahoo.com Tel: 91 3762370121 ext. 2330 Present address: Division of Medicinal, Aromatic & Economic Plants, Regional Research Laboratory (CSIR), Jorhat - 785 006, Assam, India
The nodules on maize (Zea mays L.) cv. Kiran were induced using plant growth regulator 2,4-D in nitrogen free Hoagland solution. Concentrations of 2,4-D greater than 1 ppm caused stunting and death, while less than 1 ppm had no obvious effect on seedling growth. Presence of nitrogenase activity and leghemoglobin was noticed in the plants treated with Azorhizobium either alone or with nodulated plants, but higher activity was noticed in the nodulated Azorhizobium treated plants. These results confirmed the nitrogenase activity of Azorhizobium caulinodans in association with the 2,4-D induced nodules of maize.
Azorhizobium caulinodans, 2,4-D, maize, nodulation, nitrogen fixation
