Research on Allelopathy between Different Kinds of Vegetables

Allelopathy of water extracts of cucumber, pepper, tomato and Chinese cabbage was studied by pot plant. The results show that water extracts of cucumber, pepper, tomato and Chinese cabbage have autointoxication and water extract of cucumber restrains pepper and tomato seed germination and seedling growth as well as inhibits Chinese cabbage seedling root elongation; Water extract of pepper restrains cucumber seed germination and its root growth. With the treatment of pepper water immersion, tomato and Chinese cabbage seed germination and seedling growth are restrained. Water extract of tomato promotes the seedling growth of cucumber and Chinese cabbage, but restrains their root growth. After tomato water immersion treatment, seed germination rate, height of seedling, root length and fresh weight of pepper are lower compared with original ones. Water extract of Chinese cabbage restrains seed germination and seedling growth of cucumber, tomato and pepper. It is known by subordinate function value that the order of the allelopathy of various vegetables from strong to weak is Chinese cabbage cucumber pepper tomato separately.