Rate and Timing Effects of Growth Regulating Herbicides Applications on Grain Sorghum (Sorghum bicolor) Growth and Yield

Table 7

Grain yield as affected by growth regulating herbicide rate and application timing in North Carolina.

Herbicide	Rate; g ae ha^−1	Timing; cm	Rocky Mount			Clayton		Kinston
			2012	2013	2014	2012	2013	2014
			Mg ha^−1
2,4-D	100	35	8.0	4.5	6.6	2.2	1.5	5.4
	220	35	8.5	4.2	6.0	2.4	1.6	6.1
	330	35	7.7	5.2	6.2	2.6	1.3	6.1
Dicamba	280	35	8.4	4.3	6.4	0.6	1.0	5.7
2,4-D	100	45	8.0	4.5	4.4	2.3	1.2	6.0
	220	45	8.1	4.5	3.6	2.2	1.0	5.6
	330	45	8.3	5.5	5.5	2.4	1.5	4.4
Dicamba	280	45	8.3	4.5	4.6	1.1	1.5	4.5
2,4-D	100	55	7.9	5.1	4.3	2.0	1.1	5.1
	220	55	7.9	4.7	5.1	1.8	0.4	5.1
	330	55	7.8	5.2	5.0	2.1	0.6	5.0
Dicamba	280	55	7.3	4.2	3.6	0.2	1.4	4.7
2,4-D	100	65	7.3	4.2	5.7	2.2	1.3	5.1
	220	65	7.6	4.5	4.4	1.5	0.7	5.0
	330	65	7.6	4.6	4.4	1.9	1.0	4.3
Dicamba	280	65	7.0	3.5	5.4	0.9	1.4	3.5
Weed-free control			8.2	4.9	4.8	2.3	1.3	5.8

Means within a column followed by the same letters are not different according to Fisher’s protected LSD test at .