微生物除草剂禾长蠕孢菌孢子助剂筛选

禾长蠕孢菌（Helminthosporium gramineum）是一株杂草生防潜力菌，对稻田稗草有较强的致病作用，并对水稻等主要作物安全，其活性成分孢子有望开发成微生物除草剂产品。为此，文章以生物相容性、分散力和稳定性等评判指标开展了禾长蠕孢菌孢子助剂筛选研究。结果发现，SP-20为表面活性剂、大豆油为溶剂油、羧甲基纤维素钠为稳定剂时，与孢子的生物相容性较好，对菌丝生长和孢子萌发都没有显著抑制作用。且添加SP-20后，孢子悬浮液I值为0.094，对孢子粉的分散性最佳。添加羧甲基纤维素钠作为稳定剂时，拟合直线斜率最小，为0.232，因此稳定性最好。以上助剂筛选结果将为禾长蠕孢菌孢子制剂的开发及其应用奠定基础。

Screening of adjuvants for bioherbicidal fungus Helminthosporium gramineum

 Helminthosporium gramineum was isolated from infected barnyard grass and considered as a potential biocontrol candidate based on its epidemiological traits and crop safety. Its conidia showed great promise as a bioherbicidal agent for control of barnyard grass in rice fields. Thus， this study was conducted to screen conidia adjuvants for bioherbicidal fungus H.gramineum based on the biological compatibility， dispersion force， stability and other evaluation indictors. The results showed that there was better biological compatibility when SP-20， soybean oil and CMC were considered as surfactants， vegetable oil adjuvant and stabilizer, respectively. They did not significantly inhibit the mycelia growth and conidia germination. The dispersion index （I） of conidia suspensions was 0094 after addition of SP-20 as surfactants， which indicated higher dispersion force. The slope of linear fitting was minimal as 0.232 when CMC was used as stabilizer， which showed better stability. These results of adjuvants would be helpful for developing H.gramineum formulations.