摘要： 以粳稻(郑稻18)和籼稻(绵优838)为试验材料,采用水培、盆栽及田间试验相结合,研究了水稻不同生育期对精恶唑禾草灵的敏感性及生理反应。在水稻萌发期,精恶唑禾草灵对粳稻和籼稻胚根生长的抑制中浓度(IC₅₀)分别为0.168 7,0.163 7μg/mL,表明二者在芽期对精恶唑禾草灵均较为敏感。在水稻2～3叶期喷施精恶唑禾草灵后15,30 d,籼稻的IC₅₀分别为279.56,173.49μg/mL,而试验剂量下(12.5～400μg/mL)粳稻生长抑制率低于30%,表明粳稻对精恶唑禾草灵有较高的耐药性。在粳稻4～5叶期喷施精恶唑禾草灵,结果显示,18.45 a.i g/hm²剂量对禾本科杂草防除效果较好,且对水稻生长基本没有影响,因此,田间使用精恶唑禾草灵时需要严格控制使用剂量。精恶唑禾草灵对粳稻和籼稻GSH-Px、SOD、CAT、POD等保护酶系的影响各不相同,表明2种水稻在解毒及应对精恶唑禾草灵胁迫机制上存在着差异。

关键词: 精恶唑禾草灵, 粳稻, 籼稻, 药害, 保护酶系

Abstract: Taking Japonica ( Zheng Rice 18 ) and Indica rice ( Mianyou 838 ) as the test material and combining hydroponics,potted plants and field trials,this study investigated the sensitivity and physiological responses of rice to Fenoxaprop-P-ethyl at different growth stages.In rice germination, the half maximal inhibitory concentration (IC₅₀)of Fenoxaprop-P-ethyl against radicle growth of Japonica and Indica were 0.168 7,0.163 7 μg/mL respec-tively,indicating that both were more sensitive to Fenoxaprop-P-ethyl in the bud stage. For spraying fenoxaprop-P-ethyl in the 2-3 leaf stage,the half maximal inhibitory concentration (IC₅₀) of Fenoxaprop-P-ethyl against Indica rice were 279. 56,173. 49 μg/mL for 15 days and 30 days after treatment respectively. In contrast,under test doses (12.5-400 μg/mL),the Japonica rice growth inhibition rate was less than 30%,indicating that the Japonica rice possesses higher resistance to Fenoxaprop-P-ethyl.In the field, both the injury effect and herbicidal activity of Fenoxaprop-P-ethyl on Japonica rice in 4-5 leaf stage at various concentrations were evaluated. The result revealed that Fenoxaprop-P-ethyl shows good preventive and controlling ability on grass weed at 18.45 a.i g/ha with no in-hibitory activity on rice growth.However,the dosage must be strictly controlled for the narrow range of application doses.The Fenoxaprop-P-ethyl has different effects on the protective enzyme system in these two types of rice such as GSH-Px,SOD,CAT,POD,indicating the differences for these two types of rice in both detoxification and mecha-nisms of response to the stress upon treatment with Fenoxaprop-P-ethyl.

Key words: Fenoxaprop-P-ethyl, Japonica rice, Indica rice, Phytotoxicity, Protective enzyme system

中图分类号: 

• S435.11