Glufosinate Effects on Nitrogen Nutrition, Growth, Yield, and Seed Composition in Glufosinate-Resistant and Glufosinate-Sensitive Soybean

Table 4

Glufosinate effect on shoot, root, and nodule biomass, nitrogenase activity, and root respiration in conventional (glufosinate and glyphosate sensitive) soybean under field conditions in 2009 and 2010.

Year	Sampling time	Glufosinate; rate (g/ha)	Dry biomass (mg/plant)			Nitrogenase activity (μmol ethylene formed/plant/h)	Root respiration (μmol CO2/plant/h)
			Nodule	Shoot	Root
2009	3 DAT	0	73	1248	315	3.5	29.4
		45	49	1200	273	3.7	31.0
		P	0.22	0.82	0.31	0.63	0.39
	12 DAT	0	81	3261	638	7.1	49.5
		45	77	3475	656	6.5	54.1
		P	0.68	0.42	0.62	0.50	0.32
2010	3 DAT	0	42	2110	295	3.9	35.9
		45	36	1717	236	7.8	27.7
		P	0.28	0.09	0.14	0.06	0.007
	12 DAT	0	40	3942	613	35.5	263.5
		45	35	2956	531	30.4	215.6
		P	0.18	0.02	0.24	0.03	0.001

Abbreviations: DAT: days after early postemergence application.