Question

Allelopathic effects of parthenium against avena fatua and bidens pilosa

Answer 1

Parthenin is a natural constituent of Parthenium hysterophorus with phytotoxic and allelopathic properties. Its effect on two weedy species viz. Avena fatua and Bidens pilosa was studied with a view to explore its herbicidal potential. Germination of both the weeds was reduced with increasing concentration of parthenin and a dose-response relationship was observed. This provided information on LC50 and Inhibition threshold concentrations of parthenin that could be useful for future studies. Further, parthenin also inhibited the growth of both the weeds in terms of root and shoot length and seedling dry weight. Inhibition of root growth was greater than that of shoot growth. Similar observations were made when the test weeds were grown in soil amended with different concentrations of parthenin. In addition to growth, there was a reduction of chlorophyll content in the growing seedlings. It also caused water loss in the weedy species. The study, therefore, reveals that parthenin exerts an inhibitory effect on the growth and development of both weeds and can be further explored as a herbicide for future weed management strategies.

Answer 2

Explanation:

The rabbit then strode along to the Lion by sunset. The Lion was angry at him. But the wise rabbit was calm and slowly told the Lion that it was not his fault. He told the Lion that a group of rabbits were coming to him for the day when on the way, an angry Lion attacked them all and ate all rabbits but himself. Somehow he escaped to reach safely, the rabbit said.

He said that the other Lion was challenging the supremacy of his Lordship the Lion.The Lion was naturally very enraged and asked to be taken to the location of the other Lion.

The wise rabbit agreed and led the Lion towards a deep well filled with water. Then he showed the Lion his reflection in the water of the well. The Lion was furious and started growling and naturally its image in the water, the other Lion, was also equally angry.

Then the Lion jumped into the water at the other Lion to attack it, and so lost its life in the well. Thus the wise rabbit saved the forest and its inhabitants from the proud Lion.