赤皮青冈容器苗根系生长和构型对缓释肥和菌根菌的响应

杨孟晴; 吴仁超; 王秀花; 徐卫可; 黄盛怡; 周志春; 王斌

doi:10.11674/zwyf.2023001

赤皮青冈容器苗根系生长和构型对缓释肥和菌根菌的响应

Effects of slow-release fertilizer and mycorrhizal fungi on the root growth and architecture of Cyclobalanopsis gilva container seedlings

摘要

摘要:
目的揭示缓释肥和菌根菌对赤皮青冈1年生容器苗根系生长和构型及其径级分布的影响，以提高赤皮青冈容器苗的菌根化育苗水平。
方法采用两因素析因设计进行赤皮青冈容器苗栽培试验，育苗基质由泥炭、谷壳和珍珠岩(体积比为6∶1∶3)组成。供试菌根菌为彩色豆马勃(Pisolithus tinctorius)，缓释肥养分含量为全氮 180 g/kg、有效磷 60 g/kg、全钾 120 g/kg，肥效6～7个月。设置基质中添加缓释肥1.50、2.25、3.00、3.75、4.50 kg/m³，在幼苗生长3个月后，每个施肥处理分为两组，分别进行接种与不接种菌根菌两个处理，接种组每株容器苗接种10 mL彩色豆马勃(浓度为36.28 mg/mL)。于容器苗生长季末(接种后4个月)收获，测定容器苗根系生长和构型指标。
结果不论是否接种菌根菌，添加缓释肥1.50～3.75 kg/m³对容器苗根系生长和构型影响较小，添加缓释肥4.50 kg/m³显著降低了根长。接种菌根菌对赤皮青冈根系发育有显著的促生效应，且低肥料用量下的促生效果更显著。接种菌根菌后赤皮青冈容器苗根生物量、根表面积、根系平均直径、根体积和根尖数等性状增幅较大，相比不接种处理平均分别增加了10.94%、18.73%、18.23%、42.77%和72.33%，拓扑系数和平均连接长度平均分别降低了3.11%和6.10%。以接种菌根菌并施用缓释肥3.00 kg/m³的促生效应最显著，容器苗0～0.5 mm径级根长和根表面积明显高于其它施肥处理。相关性分析结果显示，接种菌根菌后容器苗根长越长，根生物量和根表面积越大，相应分形维数越高，根系越发达。
结论接种外生菌根菌彩色豆马勃可促进赤皮青冈容器苗根系生长和构型改善，弥补施肥量偏低或偏高对根系表面积、平均直径和体积可能产生的不利影响。生产中可通过接种彩色豆马勃等外生菌根菌提高缓释肥利用效率和促进根系发育，以培育优质赤皮青冈容器苗(菌根苗)，同时降低生产成本。

Abstract:
Objectives We studied the effects of slow-release fertilizer and mycorrhizal fungi inoculation on the root growth and architecture of one-year-old container seedlings of Cyclobalanopsis gilva (C. gilva), aiming to propose fertilization measurements for health cultivation of container seedlings.
Methods Two factorial complete design was adopted to carry out a pot experiment, the cultural substrate was made of peat, grain husks and perlite (in volume ratio of 6∶1∶3), the tested mycorrhizal fungi was Pisolithus tinctorius (P. tinctorius), slow-release fertilizer contained total N 180 g/kg, available P 60 g/kg, total K 120 g/kg, and the nutrient release period was 6−7 months. The application rates of slow release fertilizer were 1.50, 2.25, 3.00, 3.75 and 4.50 kg/m³. When the container seedlings grew for 3 months, each fertilizer rate treatment was divided into two groups, one group was inoculated with 10 mL P. tinctorius solution, with concentration of 36.28 mg/mL, and the other group was not inoculated. The seedlings grew for further 4 months after the inoculation, and then harvested (the end of container seedlings growth season) for investigation of root growth and architecture indexes.
Results Slow-release fertilizer application rate within 1.50−3.75 kg/m³ did not heavily affect the root growth and architecture of C. gilva seedlings, but fertilizer rate 4.50 kg/m³ significantly reduced the root length, regardless of P. tinctorius inoculation. Inoculation of P. tinctorius showed significant promotion effect on the root development of C. gilva, especially under low fertilizer rate. Compared with non-inoculation, inoculation increased the root biomass, root surface area, mean root diameter, root volume and number of root tips by 10.94%, 18.73%, 18.23%, 42.77% and 72.33% on average, but decreased the topological index and average link length by 3.11% and 6.10%, respectively. The highest promoting effect exhibited in combination treatment of P. tinctorius inoculation and slow-release fertilizer rate 3.00 kg/m³, in which the length and surface area of roots at 0−0.5 mm diameter class were significantly higher than those in the other treatments. According to the correlation analysis results, the longer the root length of container seedling, the larger the root biomass and the larger of root surface area, and the higher the fractal dimension, and the better the root system development, respectively.
Conclusions Inoculation of P. tinctorius can promote the root growth and architecture of container seedlings of C. gilva, and compensate the possible adverse effects of low or high fertilizer application on the root surface area, average root diameter and root volume. In the production of container seedlings, P. tinctorius inoculation is recommended for improving the utilization efficiency of slow-release fertilizer and the development of roots, so producing high-quality container seedlings.

HTML全文

参考文献(37)

施引文献

资源附件(0)