电容法估测植物根系生物量研究

Estimating Plant Root Biomass Using the Electrical Capacitance Method

以玉米(Zea mays)和黄豆(Glycine max)为材料,通过对其根系电容的测量试验,结合根系收获法,探讨不同测试频率下根系电容值和根系生物量的关系,以期为进一步补充和完善植物根系特征快速无损检测技术提供一定的参考价值。结果表明:玉米、黄豆2种作物根系电容均随根系生物量的增加而增大;4种频率下(0.1,0.12,1和10 kHz)根系电容值与生物量均成极显著线性正相关(P<0.01);回归分析表明,1 kHz频率下2种作物根系电容值随生物量变化趋势较稳定,分辨率较高,回归方程的拟合度最好(R>0.9)。因此,4种频率条件下,玉米、黄豆根系的电容特性都能较好地反映根系生物量的变化,其中,1 kHz为最适测定频率。

In order to investigate the relationship between root electrical capacitance ancl blomass unaer dif- ferent measuring frequencies, maize and soybean were selected as materials in this paper. The experiments of root electrical capacitance measurement and root harvest methods were performed to provide references for improving the techniques of estimating plant roots with a rapid, non-destructive method. The results showed that the root electrical capacitance of both crops presented a rising trend along with the increase of root biomass. Significant linear and positive correlations were found between root biomass and electrical capacitance under a frequency of 0.1, 0.12, 1 and 10 kHz （P〈0.01）. Regression analysis showed the root electrical capacitance of both crops presented a stable trend and a higher resolution under the condition of 1 kHz with the change of root biomass, and the fitting degree of regression equation was the best （R〉0.9）. Consequently, the root electrical capacitance characteristics of both crops could reflect the changes of root biomass under four measuring frequencies, and 1 kHz was the most appropriate measuring frequency.