图像分辨率对草本植物根系形态学参数的影响

Influences of image resolution on herbaceous root morphological parameters

应用EPSON V7000图像扫描仪,选择不同的图像分辨率,获得了北美车前(Plantago virginica)、加拿大一枝黄花(Solidago canadensis)、小飞蓬(Conyza canadensis)和春飞蓬(Erigeron philadelphicus)4种草本植物的根系图片,应用WinRhizo根系分析软件测定了不同分辨率下的每种植物的根总长、总面积、总体积这3个参数.结果表明:不同分辨率测定对根系形态参数均存在明显影响,分辨(X)和形态参数(Y)均符合:Y=A·e(B/X),拟合的相关系数均在0.92以上.分析表明:对于不同的植物,既能保证数据精度又能有较高工作效率的图像分辨率并不相同.例如北美车前和加拿大一枝黄花根系扫描时建议图像分辨率为200 dpi,而小飞蓬和春飞蓬的图像建议的分辨率为400 dpi.

Root images of four herbaceous species （including Plantago virginica ,Solidago canadensis, Conyza calmdensis and Erig- eron philadelphicus） were obtained by using EPSON V7000 scanner with different resolutions. Root morphological parameters inclu- ding root length, diameter, volume and area were determined by using a WinRhizo root analyzing software. The results show a distinct influence of image resolution on root morphological parameter. For different herbaceous species,the optimal resolutions of root ima- ges,which would produce an acceptable precision with relative short time, vary with different species. For example, a resolution of 200 dpi was recommended for the root images of Plantago virginica and S. Canadensis, while 400 dpi for Conyza canadensis and E- rigeron philadelphicus.