Abstract: One hundred and five rice germplasms from China and other countries, and six Brazilian upland rice materials were identified for allelopathy to barnyardgrass Echinochloa crus galli (L.) Beauv.] by using the relay seeding technique with slight modification. Results showed that Zhangkuang 7, P 4, Kogyoku, IR27316, Milyang 54 and Brazilian upland rice AJ035 had strong allelopathic effect to barnyardgrass. Pot experiment showed that Gumei 2 and Zhong 156 had greater inhibition effect to barnyardgrass compared with CK, on the contrary, allelopathic material TN1 had no significant inhibition effect to barnyardgrass compared to non allelopathic material Xiushui 63. Zhong 156, which had stronger inhibition effect, was related to its plant height, meanwhile, Gumei 2 with stronger inhibition effect to barnyardgrass was due to its own allelopathic trait. The degree of inhibition of barnyardgrass became greater as the increase of rice density. It seemed that the root growth inhibition of barnyardgrass was greater in allelopathic rice than that in non allelopathic rice. TN1 had little allelopathic effect to barnyardgrass collected in the field of China National Rice Research Institute(CNRRI), which might be due to its different inhibition effect to different ecological barnyardgrass. by using the relay seeding technique with slight modification. Results showed that Zhangkuang 7, P 4, Kogyoku, IR27316, Milyang 54 and Brazilian upland rice AJ035 had strong allelopathic effect to barnyardgrass. Pot experiment showed that Gumei 2 and Zhong 156 had greater inhibition effect to barnyardgrass compared with CK, on the contrary, allelopathic material TN1 had no significant inhibition effect to barnyardgrass compared to non allelopathic material Xiushui 63. Zhong 156, which had stronger inhibition effect, was related to its plant height, meanwhile, Gumei 2 with stronger inhibition effect to barnyardgrass was due to its own allelopathic trait. The degree of inhibition of barnyardgrass became greater as the increase of rice density. It seemed that the root growth inhibition of barnyardgrass was greater in allelopathic rice than that in non allelopathic rice. TN1 had little allelopathic effect to barnyardgrass collected in the field of China National Rice Research Institute(CNRRI), which might be due to its different inhibition effect to different ecological barnyardgrass.

Key words: rice, germplasm, allelopathy, Echinochloa crusgalli, weed control

摘要： 用差时播种共培法的改进方法对105份水稻、6份巴西陆稻进行了化感作用抗稗草评价。 结果表明长匡7号、P4、Kogyoku、 IR27316、 Milyang 54和巴西陆稻AJ035等材料对无芒稗有较好的化感作用。盆栽研究表明，谷梅2 号、中156对无芒稗的抑制作用显著大于对照，而化感作用材料TN1对无芒稗的抑制作用与无化感作用材料秀水63无显著差异。中156的抑制作用强与其株高有关，而谷梅2号对无芒稗的抑制作用强主要在于其本身的化感作用。随着水稻密度增加，无芒稗受抑程度加剧，化感作用水稻对稗草根部的抑制似乎要比无化感作用水稻强。TN1对无芒稗的化感作用不明显，可能是由于对不同生态的稗的作用不同之故。

关键词: 水稻, 种质资源, 化感作用, 无芒稗, 杂草治理