宁波沿海地区水稻田稗草发生量及对丙草胺、丁草胺的抗药性检测——以6个样点为例

Detection of Echinochloa crus-galli (L.) Beauv. occurrence and its resistance to pretilachlor and butachlor in paddy fields in Ningbo coastal areas——Taking 6 sites as examples

为研究宁波沿海地区水稻田稗草发生量及对丙草胺和丁草胺的抗药性,本研究以宁波沿海地区土壤盐碱化、碱化和非盐碱化稻田的稗草及土壤中稗草种子库密度为研究对象,通过连续3年的大田试验及室内抗药性分析,研究稗草草相及土壤中稗草种子库密度变化,并对稗草的抗药性进行了分析。结果表明,在调查周期内,宁波沿海的盐碱化稻田稗草发生密度为16.23株/m^(2),显著高于土壤碱化和非盐碱化稻田中的11.70株/m^(2)和10.10株/m^(2)。盐碱化稻田稗草种子库密度为19 169.17粒/m^(2),高于土壤碱化稻田的17 224.83粒/m^(2),并显著高于非盐碱稻田的15 411.33粒/m^(2)。在庵东镇和大徐镇的盐碱稻田中,稗草对丙草胺和丁草胺的相对抗药性指数(RI)分别从调查初始期的4.51和2.88上升至调查末期的5.52和6.14,达到中抗水平;而在土壤碱化稻田和非盐碱稻田中,稗草对丙草胺和丁草胺的RI均维持在相对较低的水平,调查周期内介于1.00~2.33之间,处于低抗水平。因此,在该地区的水稻生产过程中,应尽量改善土质,以控制稗草种群规模、延缓抗药性的产生。

In order to determine the herbicide resistance of Echinochloa crus-galli(L.) Beauv. to pretilachlor and butachlor in paddy fields in Ningbo coastal areas, we took E.crus-galli and soil seed bank density in saline-alkali, alkali and non saline-alkali paddy fields in Ningbo coastal areas as the research targets, the changes of E.crus-galli population and seed bank density were investigated and the herbicide resistance was evaluated through field experiments and laboratory herbicide resistance tests during three consecutive years. The results showed that in the investigation period, the occurrence density of E.crus-galli in saline-alkali paddy fields along Ningbo coast was 16.23 plants/m^(2), significantly higher than that in alkali and non saline-alkali paddy fields, which were 11.70 and 10.10 plants/m^(2), respectively. The seed bank density of E.crus-galli in saline-alkali paddy field was 19 169.17 grain/m^(2), higher than that of 17 224.83 grain/m^(2) in alkali paddy fields and significantly higher than 15 411.33 grain/m^(2) in non saline-alkali fields. In the saline-alkali paddy fields of Andong town and Daxu town, the relative resistance index(RI) of E.crus-galli to pretilachlor and butachlor increased from 4.51 and 2.88 to 5.52 and 6.14 from the beginning of investigation period to the end, respectively. However, the RI to pretilachlor and butachlor remained at a low level in alkali and non saline-alkali paddy fields, ranging from 1.00 to 2.33 in the investigation period, which was at a low resistance level. Therefore, in the process of rice production in this area, the soil quality should be improved as much as possible to control the population size of E.crus-galli and delay the resistance.