Allelopathic Effects of Medicinal Plants on Food Crops in Garhwal, Himalaya

ABSTRACT

An aqueous leaf and root/tuber extracts of three important medicinal plant species (e.g., Bergenia ciliata, Hedychium spicatum and Potentilla fulgens) were tested for their allelopathic effects on germination, radicle and plumule elongation of Amaranthus caudatus, Eleusine coracana, Fagopyrum esculantum, Phaseolus mungoo, Phaseolus vulgaris and Triticum aestivum. The results revealed that: the allelopathic effects increased with increasing concentration of leachats from 2%, 5% to 10%. The susceptible crops were Amaranthus caudatus and Phaseolus mungoo whose germination, redicle and plumule growth were reduced significantly under aqueous extracts of all three medicinal species.

The results suggested that all the three species can be grown satisfactorily under traditional agriculture systems of subtropical-sub temperate region if whole plants of these medicinal species are harvested from the agricultural fields and nothing is left in the fields for allelopathic influence. Domesticated cultivation of medicinal plants is clearly a sustainable alternative in order to preserve this wild wealth and increase the farm income of local farmers.

KEYWORDS:

• Allelopathic effects
• aqueous root
• leaf extracts
• food crops
• germination percentage
• medicinal plants