Quantitative analysis of 3-dimensional root architecture based on image reconstruction and its application to research on phosphorus uptake in soybean

The root system is an important organ for plants not only because it absorbs water and nutrients, but also because it provides anchorage against uprooting forces1,2]. Root architecture is the spatial configuration of the root system in the growth medium…

Quantitative analysis of 3-dimensional root architecture based on image reconstruction and its application to research on phosphorus uptake in soybean

Quantification of 3-dimensional (3-D) plant root architecture is one of the most important approaches to investigating plant root growth and its function in nutrient acquisition and utilization. However, no effective methods have been reported hitherto to quantify 3-D root architecture parameters, making it difficult to further study the 3-D characteris- tics of the root system and its function. In the present study, we created a rapid algorithm to reconstruct 3-D root system images based on the basic structural features of such linear objects as roots, using 2-D root images taken by digital CCD cameras at multi- viewing angles. This method is very effective in the reconstruction of plant root system images, thus enabling us to obtain the digital model of 3-D root architecture and its 3-D skeleton, based on which some major root architecture parameters can be calculated. Using this method, we were able to ac- quire 3-D parameters of soybean root architecture whose root diameter was more than 0.3 mm, includ- ing tap root length, total root length, average basal root angle, ratio of root width to root depth, percent- age distribution of root length in different layers and root distribution in different 3-D regions of the growth medium. We also quantitatively analyzed the rela- tionship between different root architecture parame-ters and such plant nutrition parameters as soybean biomass and phosphorus (P) uptake. Our study may provide a new tool in studying the growth and nutri- tional functions of plant root systems.