Ismail B S, Siddique Mohammed Abu Bakar
School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia.
Trop Life Sci Res. 2011 May;22(1):81-9.
Experiments were carried out in the laboratory and greenhouse to determine the growth inhibitory effects of Grassohopper's cyperus (Cyperus iria L.) on the seedlings of 5 Malaysian rice varieties namely MR211, MRQ74, MR220, MR84 and MR232. Three concentrations of the aqueous extract of the weed (12.5, 25.0 and 50.0 g/l) and weed debris (5, 10 and 20 g dry debris/1000 g soil) were used to test the allelopathic effect of C. iria on the growth of the rice plants. The weed leaf, stem and root extracts reduced the growth of the rice seedlings and showed selective activity in the varieties. The C. iria leaf and stem extracts showed comparatively higher growth inhibitory effects than those from the root. The weed extract caused more reduction in the root length of the rice plant compared to the shoot length. Among the rice varieties tested, MR232 was found to be more susceptible to the weed inhibitory effect. The leaf extract of C. iria at full strength caused root and shoot reduction of MR232 by 88.1% and 73.1% respectively (compared to the control). In most cases the fresh weight of the rice seedlings were more affected than the plant height. Weed debris caused significant reduction of leaf chlorophyll content in all the rice varieties tested with the exception of MR211. The chlorophyll content of MR232 was greatly affected by the weed debris which caused reduction of 36.4% compared to the control. The inhibitory effects of weed extracts and debris on rice growth parameters were found to be concentration dependent.
在实验室和温室中开展了实验，以确定李氏莎草（Cyperus iria L.）对5个马来西亚水稻品种（即MR211、MRQ74、MR220、MR84和MR232）幼苗的生长抑制作用。使用了三种浓度的杂草水提取物（12.5、25.0和50.0克/升）和杂草残体（5、10和20克干残体/1000克土壤）来测试李氏莎草对水稻植株生长的化感作用。杂草的叶、茎和根提取物降低了水稻幼苗的生长，并在品种间表现出选择性活性。李氏莎草的叶和茎提取物显示出比根提取物更高的生长抑制作用。与地上部分长度相比，杂草提取物导致水稻植株根长度的减少更多。在所测试的水稻品种中,发现MR232对杂草的抑制作用更敏感。李氏莎草全强度叶提取物使MR232的根和地上部分分别减少了88.1%和73.1%（与对照相比）。在大多数情况下，水稻幼苗的鲜重比株高受影响更大。除MR211外，杂草残体使所有测试水稻品种的叶片叶绿素含量显著降低。MR232的叶绿素含量受杂草残体的影响很大，与对照相比减少了36.4%。发现杂草提取物和残体对水稻生长参数的抑制作用具有浓度依赖性。
