Nitrogen Fertilizer Effect on Cuttings vis-a-vis Seedlings Raised Plants in Relation to Nodulation and Nitrogen Fixation Behaviour on Pongamia pinnata under Nursery Conditions

摘要

Pongamia pinnata is a multipurpose, oil yielding small tree with a great potential to fix atmospheric nitrogen under barren land, road side plantation as well as grassland management etc. It Is easily multiplied through seed and cuttings. A comparative study was undertaken between seed and cutting raised plant in relation to Its nitrogen fixation potential so that the superior type of plants can be grown in future for field plantation to increase the productivity. Therefore, a pot culture experimentwas laid out to study the effect of nitrogen fertilizer on the cutting vis-i-vis seedling raised plants in relation to nodulation and nitrogen fixation in P. pinnata. It was observed that highest nodule numbers per plant were produced in the month of October In both cuttings and seedlings raised plants however, nitrogen and seasonal effects were observed nonsignificant Seasonally nodule formation was observed significantly different to each other. Highest and lowest nodule biomass was recorded in October and May in 40 kg N/ha and 20kg N/ h respectively. The seasonal effect on nodule biomass and nitrogenase activity did not show any significant differences.