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

Table 7

Effect of glufosinate on soybean biomass, nodule biomass, nitrogenase activity, root respiration, and shoot nitrogen content, 12 d after application under greenhouse conditions^ab.

Soybean type and glufosinate rate (g/ha)	Dry biomass (mg/plant)			Nitrogenase activity (μmol ethylene formed/plant/h)	Root respiration; (μmol CO2/plant/h)	Shoot nitrogen (%)
	Nodule	Shoot	Root
Glufosinate-resistant soybean
0	47^a	802^a	308^a	2.33^a	681^a	2.17^c
450	45^a	781^a	317^a	2.31^a	683^a	2.43^b
1350	44^a	757^a	305^a	2.41^a	672^a	2.73^a
Glyphosate-resistant soybean
0	46^a	927^a	377^a	1.01^a	263^a	2.48^c
45	52^a	890^a	381^a	0.86^a	274^a	2.81^b
135	38^b	636^b	284^b	0.64^b	223^b	3.23^a
Conventional soybean
0	48^a	930^a	321^a	1.33^a	251^a	2.35^c
45	46^a	848^a	325^a	1.13^ab	243^a	2.67^b
135	45^a	626^b	248^b	0.92^b	216^b	3.33^a

^aAverage of two greenhouse experiments each with seven replications.
^b Means within a column for each soybean type followed by the same letter are not statistically significant at the 5% level as determined by Fisher’s LSD test.