Interactive effect of mineral nitrogen and biofertilization on the growth, chemical composition and yield of celeriac plant

Abstract

The field experiment was conducted in two successive winter seasons of 2007/2008 and 2008/2009 on celeriac plants cv. Mars in sandy newly reclaimed soil at Beheira Governorate, (north of Egypt), to study the influence of biofertilization and their combination with mineral nitrogen fertilization on foliage growth and chemical composition as well as yield. Biofertilization treatments composed of mixture of nitrogen fixing bacteria (Azotobacter chroococcum and Azospirillium lipoferum) either individually or combined with mineral nitrogen fertilizer at the rates of 50, 75 and 100% of recommended rate. In most cases, plants treated with the combination of full dose of mineral nitrogen fertilization and soil inoculation with bio fertilizer recorded the highest and significant values of growth parameters, i.e., plant height, leaf number as well as fresh and dry weight of leaves chlorophyll, carotenoids, N, P and K contents in tissues of celeriac leaves. While the application of full dose gave the moderate values compared to control plants and other treatments. The joint application of full dose of mineral nitrogen and biofertilizer gave the highest yield of celeriac plants represented as the fresh leaves (green yield) and root yield. The application of 30 and 45 kg mineral N/feddan(1 feddan=0.42 hectare) companied with biofertization did not significantly reduce the yield, in general, compared the control mineral N and significantly decreased NO3 concentration in celeriac leaves. © EuroJournals Publishing, Inc. 2010.