Pollen contamination and its influence on the second generation Eucalyptus pellita seed orchard

doi:10.3969/j.issn.1000-2006.201902018

JOURNAL OF NANJING FORESTRY UNIVERSITY ›› 2020, Vol. 44 ›› Issue (2): 51-58.doi: 10.3969/j.issn.1000-2006.201902018

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Pollen contamination and its influence on the second generation Eucalyptus pellita seed orchard

LI Peng¹(), LUO Jianzhong¹^,^*(), MO Jiyou², WANG Chubiao¹, LU Wanhong¹, LIN Yan¹

1. China Eucalypt Research Centre, National Forestry and Grassland Adminisoration, Zhanjiang 524022, China
2. Guangxi Dongmen State-owned Forest Farm, Fusui 532108, China

Received:2019-02-22 Revised:2019-06-17 Online:2020-03-30 Published:2020-04-01
Contact: LUO Jianzhong E-mail:lip9310@163.com;luojz69@hotmail.com

Abstract

Abstract:

【Objective】Pollen contamination in forest tree seed orchards can affect their gene purity and genetic structure. This study aimed to understand pollen contamination patterns and its influence on important traits in high-generation Eucalyptus pellita seed orchard, an exotic species, to provide a scientific basis for its germplasm conservation and long-term improvement. 【Method】Using 167E. pellita families from four seed orchards as genetic material, with leaf morphology as discriminating traits, this study analyzed 1.5-2.0 years trial data for pollen contamination rate and its distribution as well as its effects on plant growth, health and flowering phenology. 【Result】 Eucalyptus pellita from all four sources exhibited pollen contamination. Contamination rates were significantly different (P < 0.05) between sources, ranging from 18.75% to 35.50%. Family-level contamination rate was 92.81%. The contamination rates among families (within source) were highly significantly different ( P < 0.01). Pollen contamination highly significantly affected ( P < 0.01) leaf morphological traits, mainly leading to narrower leaves with a lighter color and thinner wax layer. However, it did not significantly affect leaf attitude. The effects of pollen contamination on the leaves were mostly significant among the four sources. Pollen contamination did not significantly affect tree volume growth and flowering phenology but significantly decreased tree health index by 4.74% ( P < 0.01).【Conclusion】Pollen contamination rate in the second-generation E. pellita was at a medium level. The results can be applied in modifying the methods of genetic conservation of E. pellita and preventing genetic contamination.

Key words: Eucalyptus pellita, pollen contamination, high generation seed orchard, germplasm conservation

CLC Number:

S722

LI Peng, LUO Jianzhong, MO Jiyou, WANG Chubiao, LU Wanhong, LIN Yan. Pollen contamination and its influence on the second generation Eucalyptus pellita seed orchard[J]. JOURNAL OF NANJING FORESTRY UNIVERSITY, 2020, 44(2): 51-58.

Figures/Tables 6

Table 1

Table 2

Table 3

Fig.1

Table 4

Table 5

References 36

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来源 source No.	来源地 origin location	家系数量/个 family number	周边树种 nearby species
Ⅰ	广东湛江	104	尾细桉、赤桉等
Ⅱ	广西崇左-1	23	尾巨桉等
Ⅲ	广西崇左-2	20	尾巨桉等
Ⅳ	马来西亚沙巴州	20	尾叶桉等
V	澳大利亚	2种源	布拉斯桉等

来源号 source No.	树冠的健康程度 crown health				叶朝向 leaf attitude			叶色 leaf color			叶片形状 leaf shape			叶片革质 leaf leathery
来源号 source No.	1	2	3	4	3	5	7	1	2	3	3	5	7	1	2
Ⅰ	0.42	1.59	18.78	79.21	81.77	17.33	0.90	0.21	8.39	91.41	9.84	44.84	45.32	6.79	93.21
Ⅱ	0.30	3.29	19.16	77.25	82.34	16.17	1.50	2.10	12.57	85.33	14.97	42.81	42.22	10.78	89.22
Ⅲ	0.39	0.77	28.57	70.27	81.47	18.15	0.39	0.77	16.60	82.63	14.29	35.14	50.58	12.36	87.64
Ⅳ	0.43	4.76	29.00	65.80	84.42	15.15	0.43	0.43	23.81	75.76	12.55	49.35	38.10	16.88	83.12
V	0.00	0.00	25.00	75.00	66.67	29.17	4.17	4.17	12.50	83.33	16.67	62.50	20.83	20.83	79.17
平均mean	0.31	2.08	24.10	73.51	79.33	19.19	1.48	1.54	14.77	83.69	13.66	46.93	39.41	13.53	86.47

来源号 source No.	污染率/% contamination rate	叶色 leaf color	叶片形状 leaf shape	叶片朝向 leaf attitude	叶面革质 leaf leathery
Ⅰ	18.75 b	2.91 a	5.71 a	3.38 b	1.93 a
Ⅱ	25.75 ab	2.83 ab	5.54 a	3.38 b	1.89 ab
Ⅲ	35.50 a	2.75 b	5.51 a	3.32 b	1.83 bc
Ⅳ	28.96 ab	2.82 ab	5.74 a	3.38 b	1.87 ab
V	33.30 a	2.79 b	5.08 b	3.75 a	1.79 c
平均 mean	28.46	2.82	5.52	3.44	1.86

来源号 source No.		叶色 leaf color		叶片形状 leaf shape		叶片朝向 leaf attitude		叶面革质 leaf leathery
来源号 source No.		污染 CT	未污染 UCT	污染 CT	未污染 UCT	污染 CT	未污染 UCT	污染 CT	未污染 UCT
Ⅰ		2.53	3.00	4.45	6.00	3.44	3.37	1.64	2.00
Ⅱ		2.35	3.00	4.16	6.02	3.53	3.33	1.58	2.00
Ⅲ		2.30	3.00	4.88	5.86	3.24	3.36	1.52	2.00
Ⅳ		2.37	3.00	4.65	6.16	3.35	3.39	1.57	2.00
V		2.38	3.00	4.25	5.50	4.00	3.63	1.38	2.00
平均值 mean		2.39	3.00	4.48	5.91	3.51	3.42	1.54	2.00
P	类别间between types	<0.000 1		<0.000 1		0.174 2		<0.000 1
P	来源间(类别内)between sources(within types)	<0.000 1		0.000 2		0.124 8		0.001 1

来源号 source No.		H_t/m										开花率 flowering rate			花期 flowering phase
来源号 source No.		污染 CT		未污染 UCT	污染 CT		未污染 UCT	污染 CT		未污染 UCT	污染 CT		未污染 UCT	污染 CT		未污染 UCT
Ⅰ		6.17		6.02	6.59		6.40	3.62		3.80	0.51		0.49	1.83		1.82
Ⅱ		5.88		5.93	6.27		6.41	3.56		3.79	0.34		0.43	1.83		1.70
Ⅲ		5.69		5.66	5.68		5.87	3.43		3.70	0.28		0.30	1.70		1.93
Ⅳ		6.2		6.07	6.62		6.35	3.69		3.68	0.69		0.64	1.73		1.72
V		5.84		5.43	5.33		5.49	3.63		3.81	0.38		0.44	1.67		1.57
平均值 mean		5.96		5.82	6.10		6.10	3.59		3.76	0.44		0.46	1.75		1.75
P	类别间between types		0.313 3			0.915 7			0.000 2			0.751 6			0.912 3
P	来源间(类别内) between sources (within types)		0.000 3			0.000 1			0.000 6			<0.000 1			0.613 2

Pollen contamination and its influence on the second generation Eucalyptus pellita seed orchard

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