Development of a Simple Method for Observing Crop Plant Root System Using a Fiber Scope

为了观察生长在田间的作物根系，在微型电子显微镜系统中采用了纤维镜和便携式录像机。使用外径60 mm、内径54 mm的丙烯酸管作为微型电子管观察管。对该系统的准确性和实用性进行了检验。(1)利用该系统可以准确地测量出聚丙烯管上的铜线长度和大豆的所有分支根的长度。(2)该系统能准确地识别出土壤中丙烯酸管端面上的所有分支根系，并能准确地测量出端面上根系的长度。(3)微型电子管对大豆根系在土壤中的渗透方式影响不大。(4)田间大豆根长与根长密度呈极显著的线性相关。(5)的变异系数， ...更多信息 微型电子管法和土芯取样法的测量量较大，这意味着要对根系进行精确测量，需要进行多次单独测量。微型电子管法比土芯取样法更容易进行许多测量。(6)田间试验结果表明，在土壤水分不足的条件下，大豆根系比在土壤水分充足的条件下，根长更长，根深更深。(7)结果表明，根系发达的大豆植株从土壤中提取的水分量大于根系不发达的大豆，因此，根系发达的大豆叶片木质部水势、扩散导度和光合速率的午间降低程度小于根系不发达的大豆。因此，本研究所开发的微型电子显微镜系统是一种简单、实用的方法，可以准确地测量田间生长的大豆植株的根系。少

For observing roots of crop plants growing in the field, a fiber scope and a portable video recorder were employed in the minirhizotron system. The acrylic tube of 60 mm outer diameter and 54 mm inner diameter was used as the minirhizotron observation tube. The accuracy and the utility of the system were examined.(1) The length of copper wire and all branch roots of soybean on the acrylic tube was measured accurately with this minirhizotron system.(2) All branch roots intersected the face of the acrylic tube in the soil could be distinguished and the length of the roots on the face was measured accurately with the system.(3) It seemed that the minirhizotron tube did not affect significantly the manner of soybean root penetration in the soil.(4) There was significant linear correlation between the length of roots on the face of the minirhizotron tube and the root length density measured with soil-core sampling method in soybean growing in the field.(5) The coefficients of variation with … More the minirhizotron method and with soil-core sampling method were large, which means that many individual measurements should be taken for accurate measurements of root systems. The minirhizotron method is easier to take many measurements than the soil-core sampling method.(6) It was shown by using the system in the field that the roots penetrated deeper and the root length was larger in soybean plants grown under deficient soil moisture than in plants grown under sufficient soil moisture.(7) It was observed that the amount of water extracted from soil by the plants was larger in the soybean with well-developed root system than in poor root system and therefore the degrees of midday reduction in leaf xylem water potential, diffusive conductance and photosynthetic rate were smaller in the former than in the latter.From the results mentioned above, it could be concluded that the minirhizotron system developed in this study is a simple and useful method for measuring root systems of soybean plants growing in the field accurately. Less