施用多抗霉素后烟叶叶际微生态变化规律

多抗霉素常用于防控烟草叶斑类病害,为探究其施用后烟叶叶际微生态的变化规律,采用Illumina高通量测序技术分析了其施用后不同时期叶际微生物的菌群结构与多样性,利用Biolog-ECO技术解析了叶际微生物代谢功能。结果表明:多抗霉素施用前,健康与感病烟叶叶际真菌均主要分布于子囊菌门(64.20%、94.05%)和担子菌门(6.77%、2.40%);细菌均主要分布于变形菌门(7.16%、38.81%)和厚壁菌门(16.00%、0.78%);健康烟叶叶际真菌和细菌的多样性指数显著高于感病烟叶;健康烟叶叶际微生物代谢活性强于感病烟叶。多抗霉素施用后,感病烟叶中链格孢属、Boeremia、泛菌属、假单胞菌属的相对丰度均先降低后增加,而枝孢霉属、附球菌属、亚隔孢壳属、Symmetrospora、Stagonosporopsis、鞘氨醇单胞属等的相对丰度均先增加后降低;健康烟叶中链格孢属、附球菌属、Symmetrospora、Stagonosporopsis、鞘氨醇单胞属的相对丰度均先增加后降低,而枝孢霉属、Boeremia、泛菌属、假单胞菌属的相对丰度总体均呈下降趋势。感病烟叶叶际真菌和细菌多样性总体呈上升趋势,而健康烟叶的真菌多样性呈上升趋势、细菌多样性呈下降趋势。在代谢功能方面,多抗霉素施用后,感病与健康烟叶叶际微生物对31种碳源代谢均受到不同程度抑制,代谢活性随施药时间延长逐渐恢复。研究结果揭示了多抗霉素施用后烟叶叶际微生物菌群结构和多样性的变化规律,可为杀菌剂防控植物病害的微生态机制的研究提供参考。多抗霉素对健康烟叶菌群结构和微生物代谢的影响均高于感病烟叶,建议该药剂在生产上作为一种预防保护剂施用效果最佳。

Variations of phyllosphere microorganisms in asymptomatic and tobacco brown spot leaves before and after spraying 12% difenoconazole + fluxapyroxad SC

12%difenoconazole+fluxapyroxad SC(commercial name:Jiangong)was first released by BASF in China in 2016.It has been registered to control many diseases,including pear scab,apple Alternaria leaf spot,tomato early blight,cucumber powdery mildew,etc.This study evaluated the bioactivity of Jiangong against Alternaria alternata and explored variations of phyllosphere microorganisms in both asymptomatic and tobacco brown spot leaves at different persistence periods(0,5,10,and 15 days post-fungicide application)using high-throughput sequencing technology.The results indicated that Jiangong effectively inhibited mycelial growth(average EC_(50) value of 0.51μg/mL),conidia germination(average EC_(50) value of 3.47μg/mL),and the carbon metabolism of A.alternata.Both asymptomatic and symptomatic leaves presented complex microbial communities.Higher fungal diversity was noted in asymptomatic leaves,while higher bacterial diversity was found in symptomatic leaves.After application,the diversity and abundance of microbial community structures in both types of leaves changed over time.Fungal microbiome communities showed greater sensitivity than bacterial groups,with the microbiome communities of asymptomatic leaves being more affected than those of symptomatic leaves.Fungal community diversity decreased for both symptomatic and asymptomatic leaves after 5 days of application,while the diversity of fungal community in symptomatic leaves showed an upward trend after 10 days of application.Meanwhile,bacterial community diversity increased in both symptomatic and asymptomatic leaves after 5 days of application but then declined in asymptomatic leaves after 15 days.The abundance of the dominant function group of phyllosphere bacteria(metabolism,genetic information processing,environmental information processing)was not affected by the application of Jiangong.However,the abundance of the dominant function group of phyllosphere fungi(animal pathogen-endophyte-wood saprotroph,endophyte-plant pathogen,plant pathogen-undefined saprotroph)was significantly affected by the application of Jiangong,and high variation was found in symptomatic leaves than that of asymptomatic leaves.The application of Jiangong-induced alterations in the community structure of the tobacco phyllosphere microbiome provides a basis for future tobacco brown spot control strategies based on phyllospheric microecology.

CuCo_(2)O_(4)纳米片在有序宏孔电极板上的制备

采用水热法在表面镀镍的有序宏孔电极板(OMEP)的表面和侧壁制备了金属氧化物——CuCo_(2)O_(4)纳米片,获得一种微型且高效的活性电极材料。通过扫描电子显微镜(SEM)观察到,在OMEP上生长的纳米结构由CuCo_(2)O_(4)纳米片组成。与在OMEP上生长的Co_(3)O_(4)纳米材料相比,制备的CuCo_(2)O_(4)/OMEP电极具有更好的电化学性能,在30 mA·cm^(-2)的电流密度下电极比电容为1334 F·g^(-1)(10 F·cm^(-2)),循环5000次后的循环稳定性为86%。这种独特的三维有序多孔结构使电子和离子的输运更加便利,增大了液固界面面积,提高了活性材料的利用效率,同时还减小了电极的质量和尺寸。