五爪金龙、三裂叶薯和七爪龙水浸液对4种作物种子萌发与幼苗生长的影响

采用培养皿滤纸法,研究了强入侵植物五爪金龙、弱入侵植物三裂叶薯和海南本地植物七爪龙叶片水浸液对萝卜、白菜、芥菜和莴笋等4种作物的种子萌发与幼苗生长的影响.结果表明,五爪金龙地上叶片水浸液对4种作物种子萌发和幼苗生长都具有明显的抑制作用,且随着质量浓度的增大,抑制作用增强,低质量浓度(0.1 g· mL-1)的水浸液对白菜、莴笋、芥菜、萝卜幼苗根的抑制率分别为81.3％,80.1％,74.2％和64.8％,高质量浓度(0.5g·mL-1)的水浸液可以使各受体幼苗停止生长.七爪龙和三裂叶薯叶片水浸液为低质量浓度时促进种子生长,高质量浓度时对根具有轻微的抑制作用.高质量浓度的七爪龙叶片水浸液对白菜、莴笋、芥菜和萝卜幼苗根的抑制率分别为47.7％,59.3％,43.6％和22.8％.高质量浓度的三裂叶薯叶片水浸液对白菜、莴笋、芥菜和萝卜幼苗根的抑制率分别为78.7％,75％,49.6％和25.1％.此外,五爪金龙具有较强的化感作用,且其化感作用大于三裂叶薯和七爪龙.

Effect of Aqueous Extracts of 3 Plants (Ipomoea cairica, Ipomoea triloba and Ipomoea digitata) on Seed Germination and Seedling Growth of Radish, Cabbage, Mustard and Asparagus Lettuce

Using the petri dishes filter paper method,leaves of 3 plants （ Ipomoea cairica,Ipomoea triloba and Ipomoea digitata Linn） were extracted with water and used to treat four vegetables （ radish,cabbage,mustard and asparagus lettuce） to observe their seed germination and their seedling growth. The results showed that the leaf aqueous extract of I. cairica significantly inhibited seed germination and seedling growth of the four vegetables,and that the inhibition increased with concentration of the aqueous extract. At the low concentration （ 0. 1 g·mL-1 ） the aqueous extract of I. cairica inhibited 81. 3%,80. 1%,74. 2% and 64. 8% of the root growth of cabbage,asparagus lettuce,mustard and radish,respectively,while at higher concentration （ 0. 5 g·mL-1 ） it stopped the seedling growth of all the vegetables tested. The aqueous extracts of the native plant I. digitata and the weak invader I. triloba promoted seed growth of the vegetables at the low concentration,and gave a slight inhibition to the seed growth at the high concentration. The aqueous extract of I. digitata at the high concentration inhibited the root growth of the cabbage,asparagus lettuce,mustard and radish by 47. 7% ,59. 3% ,43. 6% and 22. 8% ,respectively,and that of I. triloba inhibited the four vegetables by 78. 7% ,75% ,49. 6% and 25. 1% ,respectively. The results suggest that the strong invader I. cairica has a higher allelopathic effect than the weak invader I. digitata and the native plant I. triloba.