Cucurbita moschata Allelopathy under Macroelement Stress

The experiment adopted hydroponic culture, biological testing and lab determination to study alleopathic effects of root exudates and extracts of Cucurbita moschata M. seedlings under the stresses of different macro elements (N, P, K, Ca, S, Mg) on Cucurbita moschata M. seedlings. The results showed that Cucurbita moschata M. had autotoxicity and the stresses of different macroelements had inhibiting effects on the growths of its radicals and plumule, different nutritious conditions exerted different impacts on its root exudates and the proper combination of nutritious elements could alleviate its autotoxicity. Organic substances extracted with ethyl acetate from the exudates of Cucurbita moschata M. roots also showed inhibiting effects on the growth of Cucurbita moschata M. radicals but to a higher extent. There existed allelopathic substances in water extracted solutions of the roots taken at the seedling stage, which inhibited the growth of Cucurbita moschata M.seedlings. Screening the optimal macroelement combination at which the exudates of Cucurbita moschata M. roots showed the least inhabitable effect on the growth of its seedling would provide the basis for Cucurbita moschata M. mechanism in response to nutrition stresses.