Potencial forrageiro de progênies S<sub>3</sub> de milho em topcrosses e seleção de testadores de diferentes bases genéticas

O objetivo deste trabalho foi identificar genótipos de milho (Zea mays) com potencial forrageiro e avaliar a eficiência dos testadores em discriminar características forrageiras em cruzamentos topcrosses, ao se considerar a contribuição de genes aditivos e não aditivos. O experimento foi conduzido nas safras de 2015/2016 e 2016/2017, no delineamento de blocos ao acaso, com três repetições. Avaliaram-se 30 progênies S₃ de milho em cruzamentos topcrosses com os testadores AG8025, P30B39, MLP102, 60.H23.1 e 70.H26.1. Foram avaliadas as seguintes características: produtividade de massa seca da forragem, fibra em detergente neutro, fibra em detergente ácido e degradabilidade da massa seca da forragem. As progênies 205.2, 159.6 e 199.2, nessa ordem, apresentaram o melhor desempenho para potencial forrageiro. Os testadores 60.H23.1 e 70.H26.1 melhor expressaram a variabilidade genética existente entre as progênies. Para todas as características nas duas safras, há o predomínio da ação de genes de efeitos não aditivos.

Termos para indexação:
Zea mays; efeitos aditivos; efeitos não aditivos; dialelo parcial

Autoria

Jocimar Costa Rosa ^**Corresponding author: joce_jcosta@hotmail.com

Universidade Estadual do Centro-Oeste, Departamento de Agronomia, Rua Simeão Camargo Varela de Sá, no 03, Vila Carli, CEP 85040-080 Guarapuava, PR, Brazil. E-mail: joce_jcosta@hotmail.com, mfaria@unicentro.br, luizzaluski@hotmail.com, emanuel_gava2@hotmail.com, pedrohw andreoli@gmail.com, vsagae@gmail.comUniversidade Estadual do Centro-OesteBrazilGuarapuava, PR, Brazil Universidade Estadual do Centro-Oeste, Departamento de Agronomia, Rua Simeão Camargo Varela de Sá, no 03, Vila Carli, CEP 85040-080 Guarapuava, PR, Brazil. E-mail: joce_jcosta@hotmail.com, mfaria@unicentro.br, luizzaluski@hotmail.com, emanuel_gava2@hotmail.com, pedrohw andreoli@gmail.com, vsagae@gmail.com

Marcos Ventura Faria

Welton Luiz Zaluski

http://orcid.org/0000-0002-4497-4160

Emanuel Gava

http://orcid.org/0000-0001-6386-973X

Pedro Henrique Willemann Andreoli

http://orcid.org/0000-0002-5988-3966

Vitor Seiti Sagae

http://orcid.org/0000-0001-5619-7576

*Corresponding author: joce_jcosta@hotmail.com

SCIMAGO INSTITUTIONS RANKINGS

Figuras | Tabelas

Figuras (6)
Tabelas (2)

Thumbnail

Figure 1.
Dry mass averages used to calculate the evaluated corn (Zea mays) forage traits.

Thumbnail

Figure 2.
Averages of the S₃ corn (Zea mays) progenies for dry mass yield (DMY), neutral detergent fiber (NDF), acid detergent fiber (ADF), and dry mass degradability (DMD), evaluated in the 2015/2016 and 2016/2017 crop seasons. The horizontal lines indicate general averages.

Thumbnail

Figure 3
Averages of the general combining ability (GCA) of the tester for the traits forage dry mass yield (DMY), neutral detergent fiber (NDF), acid detergent fiber (ADF), and dry mass degradability (DMD) of corn (Zea mays) evaluated in the 2015/2016 and 2016/2017 crop seasons.

Thumbnail

Figure 4
Estimates of the general combining ability (GCA) of the S₃ corn (Zea mays) progenies for dry mass yield (DMY), neutral detergent fiber (NDF), acid detergent fiber (ADF), and dry mass degradability (DMD), evaluated in the 2015/2016 and 2016/2017 crop seasons. The vertical lines indicate 1.5 times the standard deviation of the GCA.

Thumbnail

Figure 5
Dispersion of the estimates of the general combining ability (GCA) of corn (Zea mays) progenies (Gi) and of the specific combining ability (SCA) of the respective progenies with testers (Sij) in the 2015/2016 and 2016/2017 crop seasons, for the traits dry mass yield (DMY) and neutral detergent fiber (NDF). The vertical and horizontal axes pass through the values of 1.5 times the standard deviation for GCA and SCA, respectively.

Thumbnail

Figure 6
Dispersion of the estimates of the general combining ability (GCA) of corn (Zea mays) progenies (Gi) and of the specific combining ability (SCA) of the respective progenies with testers (Sij) in the 2015/2016 and 2016/2017 crop seasons, for the traits acid detergent fiber (ADF) and dry mass degradability (DMD). The vertical and horizontal axes pass through the values of 1.5 times the standard deviation for GCA and SCA, respectively.

Thumbnail

Table 1.
Estimates of the components of variance and the genetic parameters of corn (Zea mays) forage quality evaluated in trials with topcross hybrids obtained with 30 S₃ corn progenies and five testers (AG8025, P30B39, MLP102, 60.H23.1, and 70.H26.1).

Thumbnail

Table 2.
Summary of the joint diallel analysis of the cycle conjunction between 30 S₃ corn (Zea mays) progenies and five testers evaluated in the 2015/2016 and 2016/2017 crop seasons⁽¹⁾.

Figure 1. Dry mass averages used to calculate the evaluated corn (Zea mays) forage traits.

Figure 2. Averages of the S₃ corn (Zea mays) progenies for dry mass yield (DMY), neutral detergent fiber (NDF), acid detergent fiber (ADF), and dry mass degradability (DMD), evaluated in the 2015/2016 and 2016/2017 crop seasons. The horizontal lines indicate general averages.

Figure 3 Averages of the general combining ability (GCA) of the tester for the traits forage dry mass yield (DMY), neutral detergent fiber (NDF), acid detergent fiber (ADF), and dry mass degradability (DMD) of corn (Zea mays) evaluated in the 2015/2016 and 2016/2017 crop seasons.

Figure 4 Estimates of the general combining ability (GCA) of the S₃ corn (Zea mays) progenies for dry mass yield (DMY), neutral detergent fiber (NDF), acid detergent fiber (ADF), and dry mass degradability (DMD), evaluated in the 2015/2016 and 2016/2017 crop seasons. The vertical lines indicate 1.5 times the standard deviation of the GCA.

Figure 5 Dispersion of the estimates of the general combining ability (GCA) of corn (Zea mays) progenies (Gi) and of the specific combining ability (SCA) of the respective progenies with testers (Sij) in the 2015/2016 and 2016/2017 crop seasons, for the traits dry mass yield (DMY) and neutral detergent fiber (NDF). The vertical and horizontal axes pass through the values of 1.5 times the standard deviation for GCA and SCA, respectively.

Figure 6 Dispersion of the estimates of the general combining ability (GCA) of corn (Zea mays) progenies (Gi) and of the specific combining ability (SCA) of the respective progenies with testers (Sij) in the 2015/2016 and 2016/2017 crop seasons, for the traits acid detergent fiber (ADF) and dry mass degradability (DMD). The vertical and horizontal axes pass through the values of 1.5 times the standard deviation for GCA and SCA, respectively.

Table 1. Estimates of the components of variance and the genetic parameters of corn (Zea mays) forage quality evaluated in trials with topcross hybrids obtained with 30 S₃ corn progenies and five testers (AG8025, P30B39, MLP102, 60.H23.1, and 70.H26.1).

Genetic parameter	AG8025	P30B39	MLP102	60.H23.1	70.H26.1
	Dry mass yield
σ²_G	26,822.83	16,252.80	8,154.69	29,463.12	35,028.65
σ²	6,078.39	5,928.65	912.53	6,965.78	8,501.46
h_a²	0.80	0.79	0.58	0.81	0.85
CVg	19.57	16.08	8.95	15.37	15.69
	Neutral detergente fiber
σ²G	2.91	0.87	1.61	1.38	15.13
σ²	8.73	14.10	9.82	9.19	11.67
h_a²	0.25	0.05	0.14	0.13	0.42
CVg	3.13	1.69	2.26	2.10	6.63
	Acid detergente fiber
σ²_G	1.51	0.86	0.35	0.41	6.78
σ²	5.23	8.37	9.04	6.07	5.15
h_a²	0.22	0.09	0.03	0.07	0.56
CVg	4.26	3.10	2.00	2.18	8.71
	Dry mass degradability
σ²_G	18.13	28.12	25.41	32.55	10.53
σ²	14.34	16.15	18.55	13.41	17.44
h_a²	0.55	0.63	0.57	0.71	0.03
CVg	8.35	10.35	10.06	11.61	1.51

⁽¹⁾
σ² _G, genetic variance; σ², residual variance; h_a², broad-sense heritability; and CVg, coefficient of genetic variation.

Table 2. Summary of the joint diallel analysis of the cycle conjunction between 30 S₃ corn (Zea mays) progenies and five testers evaluated in the 2015/2016 and 2016/2017 crop seasons⁽¹⁾.

Source of variation		Degree of freedom	Medium square
Source of variation		Degree of freedom	DMY	NDF	ADF	DMD
Genotypes		184	214.41**	61.24*	30.81*	172.07**
	GCA testers	4	689.74	455.23	38.17	411.93*
	GCA progenies	29	140.34	64.20	27.85	167.52**
	SCA	150	152.39	50.44**	31.14*	157.85**
Environments (E)		1	0.8812	0.0756	0.0165	0.0064
Genotypes x environments		184	124.28	46.11	22.16	21.26
	GCA testers x E	4	273.16	247.21	38.32	39.02
	GCA progenies x E	29	98.64	34.70	16.41	10.74
	SCA x E	150	123.22	34.04	22.06	22.86
Error		736	25.68	30.40	18.39	47.49
SSGCA testers (%)			6.99	16.16	2.69	5.2
SSGCA progenies (%)			10.32	16.52	14.25	15.34
SSGCA (%)			17.31	32.68	16.94	20.55
SSSCA (%)			57.94	67.15	82.40	74.79
Group (%)			24.75	0.17	0.66	4.66
Mean			28,653.47	56.35	28.68	49.18

⁽¹⁾
GCA, general combining ability; SCA, specific combining ability; SSGCA, sum of squares of the general combining ability; SSSCA, sum of squares of the specific combining ability; DMY, forage dry mass yield; NDF, neutral detergent fiber; ADF, acid detergent fiber; and DMD, forage dry mass degradability. ** and *Significant by the F-test, at 1 and 5% probability, respectively.

Como citar

copiar

Embrapa Secretaria de Pesquisa e Desenvolvimento; Pesquisa Agropecuária Brasileira Caixa Postal 040315, 70770-901 Brasília DF Brazil, Tel. +55 61 3448-1813, Fax +55 61 3340-5483 - Brasília - DF - Brazil
E-mail: pab@embrapa.br

Acompanhe os números deste periódico no seu leitor de RSS

Versão para download de PDF

PDF

Inglês

Versões e tradução automática

Versão original do texto

English

Tradução automática

Google Translator
Microsoft Translator

Como citar

RIS

BIBTEX

Outros formatos de citação e exportação:

SciELO - Scientific Electronic Library Online
Rua Dr. Diogo de Faria, 1087 – 9º andar – Vila Clementino 04037-003 São Paulo/SP - Brasil
E-mail: scielo@scielo.org