软X射线摄影术与水浸泡结合进行南京椴选种

Upgrading Nanjing linden seeds with integrated soft X-ray photography and water separation

南京椴Tilia miqueliana种子饱满度不高,且"大小年"现象明显,人工辅助选种有利于种苗生产。利用软X射线摄影术对南京椴种子饱满度进行测定,在电压25 kV,电流3 mA,曝光时间10 s,焦片距25 cm的拍摄条件下,种子射线图像可清晰显现在乐凯2号涂塑放大纸上,从图像中可准确辨别饱满种子、发育不完全种子和空粒种子。利用这一技术对南京椴种子水选效果进行检验,浸种14 h所选种子饱满度高达87.8%,浸种26 h所选种子饱满度基本高于85.0%,浸种76 h下沉种子饱满度仍高于平均饱满度。试验证实将软X射线摄影术与水浸种结合可应用于南京椴种子大量选种,选种效率较高,精选种子饱满度可达85%以上。

The soundness of Nanjing linden （ Tilia miqueliana） seeds was low and the species had an obvious periodicity of seed bearing. Upgrading by artificial method was benefit for seed and seedling production. Soundness of the Nanjing linden seeds was measured with soft X-ray photography utilizing a voltage of 25 kV, an electric current of 3 mA, an exposure time of 10 s, and a photographic flange-focal distance of 25 cm, to produce a radiographic image that accurately distinguished the full seeds, incompletely developed seeds, and the empty seeds on No. 2 plastic coated photographic paper. The results of water separation for Nanjing linden seeds were checked using X-ray technology. It showed that the sound seed rate selected by soaking seeds in water for 14 h was 87.8% , and the sound seed rate selected by soaking seeds in water for 26 h was 85.0%. The sound seed rate of sunk seeds after soaking them in water for 76 h was still higher than average sound seed rate. This study confirmed that the method with integrated soft X-ray photography and water separation could be used for upgrading Nanjing linden seeds. The efficiency of selection was high and the sound seed rate of selected seeds using above method exceeded 85%. [ Ch, 1 fig. 1 tab. 14 ref. ]