• 论文与研究报告 •

### 杨树人工林种间混交对生长性状和食叶害虫抗性的影响

1. 1. 中国林业科学研究院森林生态环境与保护研究所 国家林业和草原局森林保护学重点实验室 北京 100091
2. 北大荒农垦集团有限公司八五五农场有限公司 密山 158327
3. 北大荒农垦集团有限公司农业发展部林业草原处 哈尔滨 150090
4. 邢台学院生物科学与工程学院 邢台 054001
• 收稿日期:2019-11-15 出版日期:2021-08-25 发布日期:2021-09-30
• 通讯作者: 张真
• 基金资助:
林业公益性行业科研专项(201504302)

### Effects of Poplar Inter-Species Mixed Plantations on Growth Characteristics and Resistance to Defoliators

Haibo Chen1,2,3,Li Guo4,Zhen Zhang1,*,Xiangbo Kong1,Sufang Zhang1,Fu Liu1

1. 1. Research Institute of Forest Ecology, Environment and Protection, CAF Key Laboratory of Forest Protection of National Forestry and Grassland Administration Beijing 100091
2. 855 Farm Co. Ltd., Beidahuang Agricultural Reclamation Group Co., Ltd Mishan 158327
3. Forestry and Grassland Division of Agricaltral Development Department, Beidahuang Agricultrual Reclamation Group Co., Ltd Harbin 150090
4. School of Biological Science and Engineering, Xingtai University Xingtai 054001
• Received:2019-11-15 Online:2021-08-25 Published:2021-09-30
• Contact: Zhen Zhang

Abstract:

Objective: In this paper, effects of poplar inter-species plantations on growth characteristics and resistance to defoliators were surveyed to explore the planting mode of poplar plantation with high quality, high resistance and high efficiency, so as to provide a theoretical basis for enriching and enhancing the economic and ecological value of poplar plantation. Method: In 2016, four dominant three-year-old poplar species (cultivar), namely Populus alba×P. berolinensis, P. simonii×P. nigra '14', P. simonii×P. nigra, and P. nigra×P. simonii 'Yingchun 5' were selected in Heilongjiang Province. The seedlings were planted with either individual species (cultivar) or 4 species (cultivars) mixed together for forestation. Total number of 2 880 three-year-old seedlings were planted with 5 treatments and 4 repeated areas covering an area of 6.7 hm2. The height, DBH and crown width of poplar trees were measured from 2016 to 2019. From 2017 to 2019, 40 sample trees of each species (cultivar) in different planting modes were randomly selected, and the branches with a length of 40 cm in 4 directions were cut. The leaves damaged by defoliators were classified into 4 categories, and the damage rate was calculated according to 4 parameters: 1/4, 1/2, 3/4 and 1. Result: There were significant differences in tree height and DBH growth rate among treatments from 2016 to 2019. However the difference of growth rate among the species (cultivars) was greater than that affected by planting methods. DBH growth rate of Populus alba×P. berolinensis in mixed forest was significantly higher than that in pure forest (P < 0.05), and DBH growth rate of P. nigra×P. simonii 'Yingchun 5' in mixed forest was significantly lower than that in pure forest (P < 0.05). From 2017 to 2019, there was a significant difference in the growth rate of crown width among treatments. The crown width of each species (cultivar) in pure forest was larger than that of the corresponding species (cultivar) in mixed forest, but the difference was not significant. There was a significant difference in the leaf damage rate among treatments. The resistance to defoliators was in order of P. alba×P. berolinensis > P. simonii×P. nigra > P. simonii×P. nigra'14'> P. nigra×P. simonii 'Yingchun 5'. The leaf damage rate in mixed forest was between 4 pure forests. The leaf damage rate of P. alba×P. berolinensis in pure forest and mixed forest was relatively stable for three consecutive years; the difference was significant between P. simonii×P. nigra and P. simonii×P. nigra'14'in mixed forest in 2017 and 2018 (P < 0.05). Conclusion: In this study, it is illuminated that the difference in growth rate among poplar species (cultivar) is significantly greater than that influenced by planting modes. P. alba×P. berolinensis is the dominant species among the four species (cultivars), and P. nigra×P. simonii 'Yingchun 5' is the relatively weak one. The poplar species (cultivar) show additive effect in mixed forest. The growth competition among species (cultivar) exists the phenomenon that the strong is stronger and the weak is weaker. The defoliators resistance between P. simonii×P. nigra and P. simonii×P. nigra'14'is significantly different in mixed forest. The leaf damage rate in mixed forest is relatively stable for three consecutive years, which is similar to the dominant tree species, P. alba×P. berolinensis in pure forest. The leaf damage rate of the other three species (cultivars) changes greatly. P. nigra×P. simonii 'Yingchun 5' has the largest leaf damage rate in mixed forest. Except for P. alba×P. berolinensis, the leaf damage rate of each species (cultivar) in mixed forest is lower than that in pure forest, showing the non-additive effect of association resistance. According to the above conclusions, we suggest that poplar plantation should strengthen the diversified allocation of tree species or cultivars, and it is better to mix the dominant tree species (cultivars), which can improve the association resistance, reduce the incidence of diseases and defoliators, and improve the stand quality and production.