Analysis on allelopathy of seed and its germination stage of Lycopersicon esculentum

Using seed germination bioassay and taking germination rate,germination energy,germination index and vigor index as indexes,the allelopathic effect of seeds and its germination stage of tomato(Lycopersicon esculentum Mill.) on seed germination of Chinese cabbage(Brassica campestris ssp.pekinensis(Lour.) G.Olsson),radish(Raphanus sativus Linn.),cucumber(Cucumis sativus Linn.) and tomato was determined,and the allelopathic effect was evaluated by allelopathic response index(RI) and allelopathic synthesis effect(SE).The results show that all seed germination indexes of Chinese cabbage,radish and cucumber cultured by 30 mg·mL-1 tomato seed extract solution are lower than those of the control;germination of tomato seed can cause decreasing of all seed germination indexes of interplanted Chinese cabbage,radish and cucumber;and exudates from tomato seedling also inhibites to seed germination of Chinese cabbage,radish and cucumber.And among four seed germination indexes,the inhibition effect on vigor index of seed is the largest.Compared with the control,0.5 and 1.0 g simulated decomposing products of tomato seedling have a promotion to seed germination rate of Chinese cabbage,radish and cucumber,but can cause decreasing of germination index and vigor index of their seeds,while 1.5 g simulated decomposing products has the largest inhibition effect on all seed germination indexes of three vegetables.And seed germination indexes of tomato also gradually decrease with mass increasing of simulated decomposing products.8,16 and 24 mg·mL-1 aqueous extract solution of tomato seedling have an obvious inhibition to seed germination of Chinese cabbage,radish,cucumber and tomato,and with rising of extract solution concentration,all seed germination indexes of vegetables tested are gradually decreasing.Generally,during tomato seed germination process,most of RI values of seed germination of vegetables tested are negative,and SE values all are negative.It is confirmed that tomato seeds contain allelochemicals,which are secreted and released during tomato seed germination process and have an inhibition to radicle growth;and also have an autotoxicity besides having inhibition effect on seed germination of other plants.