Wheat yield and npk uptake as affected by nitrogen fertilization in combination with rhizobacterin inoculation

الملخص EN

Two field experiments were performed at the experimental Farm Station of Sids Agricultural Research Station, Agricultural Research Center during the two successive seasons 2003 / 2004 and 2004 / 2005 to study the effect of inorganic nitrogen fertilizer applications (0, 25, 50 and 100% of recommended dose for wheat plants in alluvial clay soil in Beni Suef Governomrate ,i.

e.

75 kg N / fed ) and seed inoculation with biofertilizer, namely, Rhizobacterin on both grains and straw yields as well as N P K concentrations and uptake by grains and / or straw.

The experiment was laid out in a split plot design in randomized complete blocks with four replicates.

Data indicated that both grain and straw yields significantly responded to nitrogen fertilizer additions till the full recommended nitrogen rate, i.

e.

75 kg N / fed.

Results also, showed that both grain and straw yields significantly increased by seed inoculation with Rhizobacterin inoculants, where the grain yield increases were 9.6 and 8.3% as compared with un inoculated in the two growing seasons, respectively.

The best grain and straw yields were obtained when ammonium nitrate (33.5% N) was applied at 75% recommended rate, i.

e.

56.25 kg N / fed in combination with Rhizobacterin inoculation.

It was also found that increasing inorganic nitrogen fertilizer increased both N and K concentrations and uptake in grains and straw, while P concentrations and uptake did not respond to inorganic nitrogen fertilization.

Also, biofertilizer application significantly increased nitrogen concentration in grains and potassium concentrations in grains and straw.

Moreover, nitrogen and potassium uptake in grains and / or straw were significantly affected by Rhizobacterin inoculation.

On the other hand nitrogen concentration in straw as well as phosphorus concentration in grain or straw and its uptake in straw were not affected by biofertilizer treatments.

The combination between inorganic nitrogen and Rhizobacterin inoculation exert the same trend of the effect of biofertilization on NPK concentration and uptake, where, in general the highest values of NPK concentration and uptake produced by wheat plants fertilized with full recommended nitrogen rate (75 kg N / fed) or the plants inoculated with bacterial Rhizobacterin inoculants and received three fourth of recommended nitrogen rate, i.

e.

56.25 kg / fed.

It could be concluded that 75% from recommended nitrogen level combined with seed inoculation by Rhizobacterin satisfied the demands of plant nutrition and the optimum yield production, avoided excessive fertilizer applications and accordingly, reduced the costs of chemical fertilizer applications and environmental pollutions.