Intercropping systems of corn and forage grasses with application of low mesotrione herbicide rates

Correia, Núbia M.; Lenza, Ramon A. do B.

doi:10.1590/1983-21252024v3712520rc

Acessibilidade / Reportar erro

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

Scientific Article • Rev. Caatinga 37 • 2024 • https://doi.org/10.1590/1983-21252024v3712520rc copy

Intercropping systems of corn and forage grasses with application of low mesotrione herbicide rates

Sistema de consórcio de milho com gramíneas forrageiras e o uso de doses reduzidas do herbicida mesotrione

Authorship SCIMAGO INSTITUTIONS RANKINGS

ABSTRACT

Sowing forage grass species of the genera Urochloa and Panicum simultaneously with corn can hinder crop grain yield, requiring the application of low herbicide rates for suppressing their growth and preventing potential competition with corn plants. Therefore, the objective of this study was to evaluate the use of low rates of the herbicide mesotrione for inhibiting the growth of forage grass species (Urochloa ruziziensis and Panicum maximum, cultivars BRS Tamani and BRS Zuri) sown simultaneously with corn crop, as well as the recovery capacity of these grasses. Two experiments were installed, as first and second crop seasons, in a randomized experimental block design with four replications, using a 3×4 factorial arrangement and three control treatments with corn alone. Each of the three forage grasses was sown simultaneously with corn and subjected to post-emergence application of four mesotrione rates (0, 48, 96, and 144 g ha^-1) with atrazine (1.25 kg ha^-1). Weeds, forage grasses, and corn plants were evaluated. BRS Tamani was the most tolerant forage to mesotrione, while BRS Zuri was the most sensitive. The application of mesotrione + atrazine in the corn-forage grass intercropping system contributed to weed control. The tested forage grasses did not affect corn grain yield in the first or second crop season, even with no herbicide application.

Keywords:
Congo grass; BRS Tamani; BRS Zuri; Green cover; Weed management

Source of variation	First crop season - Weed control
Source of variation	10 DAA	25 DAA	0 DAH	188 DAH
Forage grasses	1.05	1.81	0.21	16.86**
Mesotrione rates	25.71**	3.05*	0.74	0.15
Forages × mesotrione rates	0.29	1.02	0.95	0.60
CV (%)	3.35	8.60	1.23	5.63
Treatments	Means (%)
Intercropping treatment	84.79	74.55	99.36	92.06
Chemical control	78.92	67.15	100.00	52.50
Infested control	0.00	0.00	0.00	0.00
Weeding control	100.00	100.00	92.19	37.50

Source of variation	Second crop season - Weed control
Source of variation	15 DAA	35 DAA	0 DAH	119 DAH
Forage grasses	0.47	0.34	1.00	8.32
Mesotrione rates	17.13**	5.29**	1.00	7.21
Forages × mesotrione rates	0.55	0.73	1.00	3.22
CV (%)	3.79	6.25	1.00	40.38
Treatments	Means (%)
Intercropping treatment	96.25	94.11	99.95	40.00
Chemical control	90.00	85.00	100.00	22.50
Infested control	0.00	0.00	0.00	0.00
Weeding control	100.00	100.00	100.00	30.00

Source of variation	First crop season
	Phytointoxication	Density	Soil cover	Dry matter
	10 DAA	25 DAA	188 DAH	188 DAH
Forage grasses	21.91**	2.39	39.75**	50.62**
Mesotrione rates	24.22**	1.76	1.55	2.43
Forages × mesotrione rates	3.41**	0.42	0.99	1.48
CV (%)	30.99	24.60	12.60	26.19
	%	Plants m²	%	kg ha^-1
Means	9.17	24.02	70.16	1572.72

Source of variation	Second crop season
	Phytointoxication		Density	Soil cover	Dry matter
	15 DAA	35 DAA	28 DAA	119 DAH	119 DAH
Forage grasses	26.66**	38.34**	20.41**	79.29**	15.17**
Mesotrione rates	34.01**	24.19**	3.12*	24.19**	9.79**
Forages × mesotrione rates	4.09**	6.08**	3.09*	4.11**	1.35
CV (%)	33.28	39.26	29.77	14.06	34.98
	%		Plants m²	%	kg ha^-1
Means	27.92	7.60	13.81	56.56	918.69

Forage grasses	Dry matter (kg ha^-1)		Soil cover (%) 188 DAH
Forage grasses	188 DAH	119 DAH	Soil cover (%) 188 DAH
Urochloa ruziziensis	737.62 b	573.09 b	54.69 b
BRS Tamani	2107.51 a	1182.76 a	81.72 a
BRS Zuri	1873.03 a	1000.24 a	74.06 a
Minimum significant difference	357.46	278.92	7.67

Source of variation	Plant population	Number of ears per hectare	Grain yield per plant	Grain yield per ear	100-grain weight	Grain yield
Forage grasses	1.17	0.59	0.58	0.58	0.58	1.20
Mesotrione rates	0.58	0.40	1.86	3.12	2.36	1.15
Forage x mesotrione	0.77	0.78	0.14	0.06	1.08	0.32
CV (%)	9.21	9.81	12.44	10.90	3.07	14.11

Treatments	Mean values
Treatments	Thousand plants per hectare	Thousand ears per hectare	g per plant	g per ear	g	kg per hectare
Intercropping	92.43	89.76	105.22	108.26	35.16	9712.54
Chemical control	91.25	87.08	120.49	126.72	36.21	10936.82
Infested control	97.92	90.42	94.83	103.94	35.38	9262.86
Weeding control	99.17	96.66	108.26	111.29	36.18	10744.59

Source of variation	Plant population	Number of ears per hectare	Grain yield per plant	Grain yield per ear	100-grain weight	Grain yield
Forage grasses	0.64	0.52	0.48	1.32	1.52	0.95
Mesotrione rates	0.05	1.34	1.44	2.24	0.46	1.18
Forage × mesotrione	0.72	0.52	0.31	0.48	0.61	0.44
CV (%)	9.72	11.82	19.53	15.98	9.71	22.68

Treatments	Mean values
Treatments	Thousand plants per hectare	Thousand ears per hectare	g per plant	g per ear	g	kg per hectare
Intercropping	67.15	62.99	56.72	60.30	19.79	3817.42
Chemical control	66.67	67.08	59.39	59.22	19.66	3918.48
Infested control	63.33	55.84	37.17	41.57	18.79	2344.91
Weeding control	66.25	64.58	57.72	58.46	19.73	3852.35

Universidade Federal Rural do Semi-Árido Avenida Francisco Mota, número 572, Bairro Presidente Costa e Silva, Cep: 5962-5900, Telefone: 55 (84) 3317-8297 - Mossoró - RN - Brazil
E-mail: caatinga@ufersa.edu.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] *Corresponding author: <nubia.correia@embrapa.br>