Allelopathic effects of Parthenium hysterophorus L. on germination and growth of onion

作者：Wakjira M^*

来源：Allelopathy Journal, 2009, 24(2): 351-361.

• Allelopathy
• aqueous extracts
• bioassay
• dry shoot residues
• germination
• onion
• Parthenium hysterophorus
• rhizosphere soil
• root residues
• seedling growth

In laboratory and greenhouse studies the aqueous extracts of leaf and flower of Parthenium hysterophorus drastically inhibited the germination and seedling growth of onion than stem and root extracts. Onion plumules were less sensitive to allelopathic effects than radicles. Increasing concentrations of extract severely inhibited the shoot growth. Root residues from growing parthenium reduced germination percentage (by 37%) followed by uprooted but not mixed (by 27%). Root residues however did not affect onion root and shoot lengths. Emergence percentage and rate were greatly reduced by rhizosphere soil collected from 0 to 15 cm radial distance from parthenium (13 and 17%, respectively). Root length greatly stimulated by rhizosphere soil whereas shoot length was not affected. This study indicated that parthenium has a clear allelopathic effect on onion germination and seedling growth even though the extent of inhibition was severe under laboratory than greenhouse conditions. Therefore, early removal of parthenium from onion fields is essential in order to minimize influences in terms of poor germination and retarded growth and the subsequent reduction in onion yield.

• 出版日期2009-10