Abstract
Bacterial pustule of soybean is caused by Xanthomonas axonopodis pv. glycines, one of the most important diseases in soybean. The symptom of bacterial pustule is mainly distributed around leaf veins. However, the reason has not been known. In order to determine pathosystem of bacterial pustule in leaf, soybean leaves were collected and observed using scanning electron microscopy (SEM) and light microscopy. Many hairs were observed at abaxial sides of the leaf, few hairs were observed at tissue around the leaf veins. In addition, unidentified bacterial cells and dusts at the no hair part near veins were observed. In the inoculation assays, the cells of X. axonopodis pv. glycines were observed near leaf veins. The imprint of underside of soybean leaves inoculated with X.axonopodis pv. glycines on PDA showed that the growth of bacteria around veins was observed but no bacterial growth at the part with leaf hairs. Our data demonstrated that soybean leaf hairs play an important role as a physical barrier for structural resistance of soybean against bacterial pustule pathogen.
콩에 발생하는 불마름병은 주로 엽맥을 따라 병징이 형성되며, 이러한 병징의 형성에 대한 원인을 밝히고자 광학현미경 및 주사전자현미경으로 표면을 관찰하였다. 광학현미경 관찰에 의한 조직의 차이는 볼 수 없었으나 주사전자현미경으로 표면 관찰시, 잎 뒷면 미세한 엽모가 잎표면에 존재하였으며 엽맥 주위로는 엽모가 관찰되지 않았다. 세균은 엽맥 주위 엽모가 없는 부분에 주로 부착되어 있었고, 엽모가 있는 부분에서 세균은 관찰되지 않았다. 또한 잎에 불마름병균을 접종 후 표면 미생물을 배양시 엽맥주위에서 주로 세균이 검출되어 엽모의 존재가 불마름병균의 부착을 방해하여 엽맥주변으로 병징이 발현된 것으로 판단된다.
