Department of Botany and Microbiology, CCS Haryana Agricultural University, Hisar-125 004
The C2H4 evolution rate of Cicer arietinum roots was increased by 5 to 10 fold with NO−3 as compared to control but when Ag NO−3 was given with NO−3 the rate of C2H4 evolution declined by more than 50%. Nodule initiation whcih was delayed by 10 and 16 days with 10 and 20 m mol NO−3 dm−3 was restored by 4 and 6 days respectively, with Ag NO3. A negative correlation between the rate of C2H4 evolution of roots and nodule initiation was recorded. The present study suggests that NO−3 induced decline in nodulation could be mediated through the enhanced production of phytohormone, ethylene.
