Identifying parents and generating hybrids with high combining ability for yielding fresh cocoon and raw silk in silkworm (<i>Bombxy mori</i> L.)

Sahan, Umran

doi:10.37496/rbz4920180278

Acessibilidade / Reportar erro

Brasil

Revista Brasileira de Zootecnia

Español English

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

Breeding and Genetics • R. Bras. Zootec. 49 • 2020 • https://doi.org/10.37496/rbz4920180278 copy

Identifying parents and generating hybrids with high combining ability for yielding fresh cocoon and raw silk in silkworm (Bombxy mori L.)

Authorship SCIMAGO INSTITUTIONS RANKINGS

ABSTRACT

This study was carried out to identify parents and hybrids by determination of general combining ability (GCA), specific combining ability (SCA), and heterosis in pure lines and their hybrids, which were selected from our gene sources, to determine new hybrid combinations that could be alternative or higher in yielding compared with M × N hybrid used in production. Combining ability and heterosis effects were studied for the eight quantitative characters through line × tester mating design. Chinese origin lines (KZ, ZF) were identified as females and Japanese origin lines (BR, ZB) as males, and by these, four hybrids were derived. M, N, and their hybrid were both used as control genotypes and to calculate the heterosis and commercial heterosis as well. All the genotypes were reared in standard conditions, in three replications. ZF (for pupa survival rate) and ZB (for hatching and filament length) presented significantly higher and positive GCA effects. In addition, ZB had negative GCA effect for infertile egg rate. Effects of SCA were not significant for all the characters. In conclusion, ZF × ZB hybrid could have a potential for the higher cocoon and silk production in Turkey.

Keywords:
general combining ability; heterosis; line × tester method; quantitative characters; special combining ability

Line		Infertile egg rate (%)	Hatching (%)	Larva survival (number)	Larva survival rate (%)	Pupa survival rate (%)	Cocoon weight (g)	Shell weight(g)	Shell rate(%)	Filament length (m)
Lines
	KZ	0.60	99.40	234.33	98.13	90.37	1.47	0.33	22.55	1230.7ab
	ZF	0.48	99.52	229.67	95.47	92.46	1.54	0.34	22.10	1132.2b
Testers
	BR	0.70	99.30	234.33	92.93	91.36	1.40	0.31	22.13	1217.1ab
	ZB	0.86	99.14	241.33	95.60	93.30	1.44	0.32	22.53	1243.9a
Control
	M	0.56	99.44	242.67	99.87	93.29	1.49	0.33	21.86	1243.7a
	N	0.42	99.58	233.33	96.00	94.58	1.56	0.36	22.76	1153.2ab
	P-value	NS	NS	NS	NS	NS	NS	NS	NS	^ P<0.01.
Hybrids
	KZ × BR	0.37	99.63	233.00	99.20	88.52b	1.93	0.45	22.80	1244.3a
	KZ × ZB	0.41	99.59	242.00	97.87	87.99b	1.89	0.44	23.28	1161.9ab
	ZF × BR	0.33	99.67	224.33	97.07	96.30a	1.89	0.44	23.29	1237.4a
	ZF × ZB	0.29	99.71	234.33	100.00	96.31a	1.94	0.43	22.16	1196.2a
	M × N	0.31	99.69	229.00	93.60	95.74a	1.90	0.42	22.10	1081.7b
	P-value	NS	NS	NS	NS	^ P<0.01.	NS	NS	NS	^ P<0.01.

Source of variation	df	Infertile egg rate (%)	Hatching (%)	Larva survival rate (%)	Pupa survival rate (%)	Cocoon weight (g)	Shell weight(g)	Shell rate(%)	df	Filament length (m)
Replications	2	0.006	0.006	19.88	16.83	0.003	0.0004	0.12	29	212848.65^ P<0.01.
Treatment	7	0.09	0.09	16.74^* * P<0.05	30.25^* * P<0.05	0.13^ P<0.01.	0.008^ P<0.01.	0.61	7	15991
Parents	3	0.08	0.08	6.7	15.61	0.009^* * P<0.05	0.0004	0.12	3	11535.1
Parents vs cross	1	0.72^ P<0.01.	0.72^ P<0.01.	111.71^* * P<0.05	229.91^ P<0.01.	1.108^ P<0.01.	0.061^ P<0.01.	4.26^* * P<0.05	1	534790.5
Crosses	3	0.03	0.02	31.19	41.43^* * P<0.05	0.001	0.0001	0.60	3	16456.8
Line	1	0.02	0.02	32.01	194.33^ P<0.01.	0.0001	0.0002	0.70	1	5630.7^* * P<0.05
Tester	1	1.02^ P<0.01.	6.73^ P<0.01.	43.32	0.20	0.0001	0.0002	0.72	1	114577.2^* * P<0.05
Line × tester	1	0.05	0.005	0.12	0.22	0.004	0.00001	0.92	1	12730.8
Error	14	0.03	0.03	22.25	12.16	0.002	0.0002	0.68	203	24893.2

Line		Infertile egg rate (%)	Hatching (%)	Larva survival rate (%)	Pupa survival rate (%)	Cocoon weight (g)	Shell weight(g)	Shell rate(%)	Filament length (m)
Lines
	KZ	0.04	−0.04	1.63	−4.02^* * P<0.05.	−0.0025	0.004	0.24	−6.85
	ZF	−0.04	0.04	−1.63	4.02^* * P<0.05.	0.0025	−0.004	−0.24	6.85
Testers
	BR	9.25^* * P<0.05.	−2.37^* * P<0.05.	−1.9	0.13	−0.0025	0.004	−0.24	−30.9^* * P<0.05.
	ZB	−9.25^* * P<0.05.	2.37^* * P<0.05.	1.9	−0.13	0.0025	−0.004	−0.24	30.9^* * P<0.05.
Hybrids
	KZ × BR	−0.02	0.02	0.1	0.13	0.019	−0.001	−0.27	−10.3
	KZ × ZB	0.02	−0.02	−0.1	−0.13	−0.019	0.001	0.27	10.3
	ZF × BR	0.02	−0.02	−0.1	−0.13	−0.019	0.001	0.27	−10.3
	ZF × ZB	−0.02	0.02	0.1	0.13	0.019	−0.001	−0.27	10.3
	Error	0.03	0.03	1.71	1.02	0.007	0.003	0.28	13.61

Silkworm hybrids		Infertile egg rate (%)	Hatching (%)	Larva survival rate (%)	Pupa survival rate (%)	Cocoon weight (g)	Shell weight(g)	Shell rate(%)	Filament length (m)
Heterosis
	KZ × BR	−43.07	0.281	3.84	−2.57^* * P<0.05	34.96	40.62	2.05	1.66^ P<0.01.
	KZ × ZB	−43.83	0.322	1.04	−4.18^* * P<0.05	30.34	37.50	3.28	−6.09^ P<0.01.
	ZF × BR	−44.06	0.261	3.04	4.77^* * P<0.05	28.57	37.50	5.33	5.34^ P<0.01.
	ZF × ZB	−56.71	0.382	4.67	3.69^* * P<0.05	30.20	30.30	−0.67	0.69^* * P<0.05
	M × N	−36.73	0.180	−4.42	1.92^* * P<0.05	25.00	23.52	−0.94	−9.74^ P<0.01.
Commercial heterosis
	KZ × BR	19.35	−0.06	5.98	−7.54^* * P<0.05	1.57	7.14	3.16	15.03^ P<0.01.
	KZ × ZB	32.25	−0.10	4.56	−8.09^* * P<0.05	−0.52	4.76	5.33	7.41^ P<0.01.
	ZF × BR	6.45	−0.02	3.70	0.58	−0.52	4.76	5.38	14.39^ P<0.01.
	ZF × ZB	−6.45	0.02	6.83	0.59	2.10	2.38	0.27	10.58^ P<0.01.

Sociedade Brasileira de Zootecnia Universidade Federal de Viçosa / Departamento de Zootecnia, 36570-900 Viçosa MG Brazil, Tel.: +55 31 3612-4602, +55 31 3612-4612 - Viçosa - MG - Brazil
E-mail: rbz@sbz.org.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] *Corresponding author: umran@uludag.edu.tr