A comparative study on seed treatment methods for the control of rice bakanae disease
水稻恶苗病防治种子处理方法比较研究

摘要

目的 明确不同种子处理方法对水稻恶苗病的防控效果的影响，为生产上水稻恶苗病的高效防治提供科学依据。方法 选用 5 种具有代表性的水稻恶苗病防治药剂，设置 9 种种子处理方案，涵盖常规浸种、密封浸种、干种包衣及催芽后包衣等处理方式。种子处理后采用叠盘育秧模式培育 25 d，测定秧苗株高、茎基宽、根长、根数、地上部鲜重及病株数等指标，并计算恶苗病防治效果。结果 与对照相比，5 种药剂的不同种子处理方法对水稻发芽率和出苗率无显著影响；总体而言，种子包衣处理对水稻恶苗病的防治效果显著优于种子浸种处理，且对水稻秧苗具有矮壮调控作用，但该效果受药剂种类影响存在差异；对于同一种药剂，种子包衣干籽直播处理的恶苗病防效最佳，其次为种子浸种催芽露白后包衣处理和干种子包衣浸种处理；同一种药剂的常规浸种处理与密封浸种处理之间，恶苗病防治效果无显著差异。结论 生产实践中，推荐选用 11% 氟唑环菌胺・咯菌腈・精甲霜灵悬浮种衣剂或 6.25% 精甲霜灵・咯菌腈悬浮种衣剂进行种子包衣处理，以及 4.23% 种菌唑・甲霜灵微乳剂进行浸种处理，用于水稻恶苗病的高效防控；针对工厂化育秧场景，建议优先采用 11% 氟唑环菌胺・咯菌腈・精甲霜灵悬浮种衣剂包衣干籽直播的处理方式。

Abstract

Objective This study aimed to clarify the control effect of different seed treatment methods on rice bakanae disease (RBD), so as to provide a scientific basis for the efficient control of RBD.
Methods Five representative fungicides for RBD were selected, and nine seed treatment methods were set up, including conventional seed soaking, sealed seed soaking, dry seed coating, and post-germination coating. After seed treatment, the seedlings were cultivated for 25 days using rice seedlings cultivation. Seedling quality such as seedling height, stem base width, root length, root number, above-ground fresh weight, and number of diseased plants were determined, and the control effect of RBD was calculated.
Results Compared with the control, the different seed treatment methods of the five fungicides had no significant effect on rice germination rate and emergence rate. In general, the control effect of seed coating treatment on RBD was significantly better than that of seed soaking treatment, and it had a dwarfing and strengthening regulatory effect on rice seedlings, but this effect varied with the type of fungicide. For the same fungicide, the dry-seed direct seeding with seed coating showed the best control effect on RBD, followed by the post-germination coating and the seed soaking treatment with dry seed coating. There was no significant difference in the control effect of RBD between conventional seed soaking and sealed seed soaking treatments for the same fungicide.
Conclusion   In production practice, it is recommended to use 11% fluxapyroxad·fludioxonil·metalaxyl-M suspension seed coating agent or 6.25% metalaxyl-M·fludioxonil suspension seed coating agent for seed coating treatment, and 4.23% ipconazole·metalaxyl microemulsion for seed soaking treatment to achieve efficient control of RBD. For the factory seedling raising scenario, it is suggested to give priority to the dry-seed direct seeding method coated with 11% fluxapyroxad·fludioxonil·metalaxyl-M suspension seed coating agent.