Effects of nitrogen forms on yield of sorghum (Andropogen sorghum)‎ and their residual effect on a following wheat crop on a sandy soil

الملخص EN

Two field experiments were carried out on a sandy soil at Ismailia Agric.

Res.

Station, Ismailia governorate Egypt in a split plot design.

The first experiment was during summer 2016 on sorghum (Andropogen sorghum, v.

Dorado).

The main plots contained treatments of fertilizer nitrogen forms, i.e.

Ammonium Nitrate 33%N, Urea 46 %N Urea Formaldehyde 40%N and Neem Coated Urea 40%N on sorghum.

Four rates of i.e.

190,238and286 Kg N /ha(80, 100 and 120 kg N/fed) were arranged in the sub main plots.

The second field experiment was carried out during the following winter, season of 2016- 2017 growing wheat (Tricticum aestivum), on the same plots of the first experiment, to study the residual effect.

Results obtained the increases the rate of caused a significant increase in grains and straw yields of sorghum, as well as grain yield of the following wheat.

The highest mean values of soil total-N as well as and available-N occurred after wheat harvest in soil given the 238 kg/ha in rate as urea formaldehyde or Neem coated urea.