A Study of a Non-destructive Measurement Method for Judging the Growth Stage of Gentian for Flower Harvest and Quality Control

随机存在于龙胆属植物的切花中的授粉花，被认为是降低整体市场价值的主要原因。因为它经常从原来的颜色变成铜色到达市场，所以整体形象恶化的风险很高。因此，有必要在收获后立即取出授粉的花朵。然而，在目前的情况下，大多数农民只能通过观察外观来检测并手动清除它。因此，通常应留下一些授粉花。'，这是岩手县的主要种类，幼花和田间刚授粉的花之间的明显差异是如此细微，以至于授粉花的去除相当不充分。另一方面，即使在这种情况下，一些熟练的农民也可以通过仔细检查外观来检测授粉花。然而，为了推广他们的技术，有必要客观地阐明他们的感官和主观区分方法。用一种简易的测量装置，从可见光和红外两个波段，对幼花和授粉花花瓣外表面的光谱辐亮度差异进行了细致的测量。结果表明，在720nm附近的波长处，两者的差异显著。因此，在不久的将来，将有可能通过廉价的图片拍摄来开发授粉花的早期检测装置，因为在大多数商业摄像机中使用的普通图像传感器CCD对该波长具有敏感性。

The pollinated flower, which exists randomly in a cut flower of Gentiana Sp., is known as the main cause which decreases market value of the whole. Because it often arrives to market with color changed in copper from its original color, the risk that deteriorates figure of the whole is very high.Because of this reason, it is necessary to remove the pollinated flower promptly after harvest unitl shipment. However, under present circumstances, most farmer should detect it only with observation of appearance and remove it manually. Therefore, some pollinated flower should be left usually.On 'Ashiro no natsu, Gentiana sp.', which is the leading kind in Iwate prefecture, apparent difference between the young flower and the flower which has just pollinated in field is so subtle that removal of the pollinated flower is considerably insufficient. On the other hand, even on this kind, a few skillful farmers are possible to detect the pollinated flower with careful inspection of appearance. However, to spread their technology, it is necessary to elucidate their sensuous and subjective distinction method objectively.In this study, targeting 'Ashiro no natsu, Gentiana sp.', difference of spectral radiance on the outer surface of petal between the young flower and the pollinated flower was examined closely from visible wave length over infrared with a simplified measuring device. As a result, a significant difference was ascertained especially in the wave length of 720nm neighborhood. Thus, in the near future, it will be possible to develop early detection device of the pollinated flower by picture photographing inexpensively, because the CCD, which is commonplace image sensor used in most commercial video camera, has sensibility to this wave length.