Effect of Nitrogen Sources on Microbial Biomass Nitrogen under Different Soil Types

Table 2

Ammonium concentration, nitrogen uptake, and SDW (combined of two years) of rice cv. Giza 177 as affected by nitrogen sources and microbial biomass.

Treatments	Clay soil				Loamy soil
	TN in soil (%)	NH4 (mg kg^−1)	N uptake (mg pot^−1)	SDW (g pot^−1)	TN in soil (%)	NH4 (mg kg^−1)	N uptake (mg pot^−1)	SDW (g pot^−1)
Nitrogen sources
Zero N	0.25	14.31	160	10.79	0.10	11.25	60	3.91
Urea	0.41	21.44	430	21.83	0.19	15.45	110	9.43
Straw	0.42	23.93	580	21.15	0.21	19.50	160	11.10
Sludge	0.43	22.77	600	21.55	0.22	18.72	220	12.94
𝐹 test	*	*	*	*	*	*	*	*
LSD 5%	0.02	0.80	26.4	0.72	0.03	1.75	33.5	3.14
Microbial biomass
Autoclaved soil	0.39	20.88	324	16.07	0.21	16.85	84	7.06
Fresh soil	0.43	20.25	565	19.52	0.45	18.05	143	7.62
𝐹 test	*	*	*	*	*	*	*	*
LSD 5%	0.04	0.22	31.3	0.75	—	0.28	18.1	0.26

*Significant at 𝑃≤0.05, ns: not significant, and SDW: shoot dry weight of rice.