Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (1): 62-73.DOI: 10.17521/cjpe.2021.0255

Special Issue: 根系生态学

• Research Articles • Previous Articles     Next Articles

Growth of chestnut and tea seedlings under different root partitioning patterns

Nan DONG1, Ming-Ming TANG1, Wen-Qian CUI1,2, Meng-Yao YUE1,3, Jie LIU1,2, Yu-Jie HUANG1,*()   

  1. 1Xinyang Agriculture and Forestry University, Xinyang, Henan 464000, China
    2College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
    3College of Land Science and Technology, China Agricultural University, Beijing 100193, China
  • Received:2021-07-07 Accepted:2021-08-31 Online:2022-01-20 Published:2022-04-13
  • Contact: Yu-Jie HUANG

Abstract:

Aims The study aims to find the relationship between root interspecific interactions and root morphological characteristics, plant height and ground diameter accumulations. The effects of different division methods for the root interaction and interspecific interaction dynamics of chestnut (Castanea mollissima)/tea (Camellia sinensis) agroforestry systems were investigated, in order to provide the scientific basis for the sustainable development in chestnut/tea agroforestry systems. Methods The potting experiment set three cropping system, chestnut/tea agroforestry system, monocropping chestnut and monocropping tea as research objects, and three division methods with solid, mesh, and without root barrier under chestnut and tea roots. Plant height and ground diameter data were fitted to logistic growth models to investigate the temporal dynamics of plant growth, and the allometric relationship between plant height and ground diameter of chestnut and tea were fitted to power function. The relationships between plant growth and root interspecific interaction were analyzed in terms of the fine roots developments. Important findings The results showed that the aboveground dry mass, belowground dry mass, total plant dry mass, root length, root surface area, root volume, fractal abundance and root length of fine roots (0.2-1.0 mm) of intercropped tea with plastic separation were significantly increased by 357.1%, 281.8%, 345.2%, 74.3%, 273.9%, 244.8%, 42.0% and 382.4%, respectively, compared with those of the corresponding sole tea. The asymptotic value of plant height of the intercropped tea with plastic separation was 30.9% higher than the monoculture tea. The asymptotic value of plant height and ground diameter of the chestnut with nylon separation was 21.9% and 28.2% higher than the monoculture chestnut, respectively. In the division methods with plastic, intercropped tea significantly postponed the timing to reach the maximum daily plant height growth rates about 14 days, and intercropped chestnut markedly postponed the timing to reach the maximum daily ground diameter growth rates about 15 days compared with corresponding monocultures. There was significantly positive relationship between plant height and ground diameter of both chestnut and tea in the different treatments. In addition, the slopes of the growth equations about both intercropped chestnut and tea without separation were flatter than the other treatments, which were both lower than 1. Therefore, when tea is intercropped with chestnut trees, chestnut tree shading enhanced the growth of lateral root branches, fine root length and plant height, and facilitated the intercropped tea seedling dry mass accumulation. However, with the growing stresses of underground interspecific competition for intercropped chestnut, the aboveground interspecific facilitation was overridden gradually by the interspecific underground competition, and the final net outcome was manifested as neutral effects.

Key words: logistic growth models, allometric growth, plant height, ground diameter, fine root, fractal dimension