遵义烟区杂草调查及海洋杂色曲霉提取物除草效果研究

为了开发新型、安全、高效的天然产物除草剂，采用倒置“W”九点取样法和三层三级目测法对贵州省遵义市道真县和余庆县烟田杂草危害情况进行调查，明确优势杂草种类和防治需求；对具有显著除双子叶杂草活性的海洋杂色曲霉AspergillusversicolorD5进行发酵提取，明确活性成分及含量；进而采用茎叶喷雾法评价D5发酵提取物的田间除草效果。结果表明：（1）道真烟田中共有9科15种杂草发生，以双子叶菊科种类最多，以苋科相对多度值最高，占比高达84.2%，是优势杂草；余庆烟田中共有16科39种杂草发生，危害度为Ⅰ级、Ⅱ级、Ⅲ级的杂草分别有29种、9种、1种，危害度达到Ⅲ级的为双子叶杂草蓼；（2）海洋杂色曲霉D5发酵提取物在10%乙酸乙酯-石油醚洗脱后，采用100%乙酸乙酯洗脱，浓缩后活性物质基本无损失，包含柄曲霉素ST(14.6%)和二氢柄曲霉素DHST(0.4%);(3)田间小区试验发现，D5发酵提取物在低施药量（675g/hm2）下具有显著的除草作用，特别是对双子叶杂草具有明显的抑制效果，以对玄参科杂草婆婆纳Veronicadidyma最为显著，鲜质量防效达到61.4%；同时，对狗尾草Set...

Weed Investigation in Zunyi Tobacco Areas and Study on Herbicidal Effects of Marine Aspergillus versicolor Extract

In order to develop new, safe and efficient natural product herbicides, the weed harm in tobacco fields were investigated by the inverted "W" nine-point sampling method and by the three-layer and three-level visual observation method in Daozhen County and Yuqing County, Zunyi City, Guizhou Province, to clarify the dominant weed species and control needs. Aspergillus versicolor D5, which had significant herbicidal activity against dicotyledonous weeds in indoor pot experiments, was fermentated and extracted, and the active ingredients and contents were clarified. Then the herbicidal effect of D5 fermented extract was evaluated by stem and leaf spraying in the field. The results showed that:(1) There were 15 species of weeds belonging to 9 families in Daozhen tobacco fields. Dicotyledonous Asteraceae was the most diverse family, and Amaranthaceae was the dominant family as it had the highest relative abundance value of 84.2% in total weeds. A total of 39 weeds in 16 families occurred in Yuqing tobacco fields. There were 29 species, 9 species, and 1 species of weeds with hazard grade Ⅰ, Ⅱ and Ⅲ respectively. The dicotyledonous Polygonum was classified as hazard grade III. (2) Marine Aspergillus versicolor D5 fermented extract was eluted with 10% ethyl acetate-petroleum ether and then eluted with 100% ethyl acetate. There was basically no loss of active substances after concentration, including ST (14.6%) and DHST (0.4%). (3) Field trials found that, at a low dosage (675 g/ha), the fermented extract of D5 had a significant herbicidal effect, especially on dicotyledonous weeds, especially on Veronica didyma, with the fresh mass control effect of 61.4%. Meanwhile, the fresh mass control effect against Setaria viridis and Calystegia hederacea also reached more than 50%. Therefore, the fermentation extract of D5 has a broad anti-weed spectrum and significant herbicidal effect on dicotyledonous weeds, and has the potential to be developed into a new natural product herbicide.