向日葵锈菌夏孢子萌发条件的研究

以向日葵锈菌330生理小种为材料,研究了夏孢子萌发的适宜条件和培养载体。向日葵锈菌夏孢子萌发适宜温度范围10~25℃,最适温度15℃。15℃下在琼脂薄膜上1h即可萌发,12h达到萌发高峰,萌发率最高可达97%。孢子在无菌水中萌发最适浓度为20mg/L,萌发率随浓度增大而降低。光照在前5h均抑制夏孢子萌发,但7h后光照对夏孢子总萌发率基本无影响。新鲜夏孢子萌发率较高,在室温放置270d后基本丧失萌发能力。最适条件下,在供试的6种不同萌发载体上,夏孢子萌发率、芽管长度及萌发形态显著不同,琼脂薄膜载玻片、尼龙纱网、玻璃纸较适宜夏孢子萌发,萌发率超过90%;在PVDF膜和亲水滤膜上可观测到芽管内部黄色物质转移和特殊结构的形成。

Germination conditions of the urediospores of Puccinia helianthi

The urediniospores of the race 330 of Puccinia helianthi were used to explore the optimal germination conditions and culture substrates.The urediniospores began to germinate in 1 h at 15℃ and reached the maximum germination rate of 97% in 12 hours in vitro .The results showed that the suitable range of temperature for uredi-niospore germination was 10-25℃,and the optimal temperature was around 15℃.The optimal inoculation con-centration was 20 mg/L in water.Light had inhibitive effect on germination within 5 hours after inoculation,but no inhibitive effect at 7 h.Fresh spores were used for study to assure a high percentage of germination,and it was ascertained that the urediniospores had lost their germination abilities after stored for nine months at room tem-perature.By microscopy,we found that there was significant difference in germination rate and length of uredin-iospore germ tubes on the six culture substrates under the optimal temperature and humidity conditions.The ger-mination rate of urediniospores exceeded 90% on hydrophilic slide,nylon gauze and cellophane paper.Moreover, we could observe movement of yellow particulates in the germinated tubes and formation of special structure on PVDF film and millipore filter.