Allelopathic Effect of Pinellia ternata Tuber Extracts on Brassicaceous Vegetables

ZHANG Liang;LIN Ning;ZHOU Xing;School of Chemistry and Bioengineering,Taizhou College,Nanjing Normal University;Taizhou Higher Vocational School of Mechanical & Electrical Technology;

Pinellia ternata tuber extracts(PTE);;Brassicaceous vegetable;;allelopathic effect;;vegeable

Seed germination,seedling growth and relative physiological indexes of Raphanus sativus,Brassica chinensis and Brassica pekinensis seeds treated with different PTE concentration were analyzed by using the culture testing method to study allelopathic effect of P.ternatatuber extracts(PTE)on seed germination and seedling growth of R.sativus,B.chinensis and B.pekinensis and to improve land productivity.The results showed that low PTE concentration has no obvious effects on seed germination rate,germination index,vigor index and seed membrane permeability but seed membrane permeability increases with increase of PTE concentration,which results in inhibition of seed germination.Seed germination rate of R.sativus,B.chinensis and B.pekinensis seeds treated with 20mg/L PTE is 32.8%,29.5% and 29.1%lower than CK,and their soluble sugar and soluble protein content are lower than CK significantly.The nitrate reductase activity and chlorophyll content of R.sativus,Brassica chinensis and B.pekinensis seedlings treated with low PTE concentration have no significant change but high PTE concentration has the inhibition effect on nitrate reductase activity and chlorophyll content of R.sativus,B.chinensis and B.pekinensis seedlings and inhibits synthesis and accumulation of nutrient substance in endosperm.In conclusion,P.ternate root exudates and allelochemicals released from residual P.ternate plants in soil can inhibit seed germination and seedling growth of P.ternate,and the inhibition effect may insult in yield decrease substantially or total failure of next crops in the soil of intensive P.ternata cultivation.