Chemical pre-treatments improve seed germination and seedling growth in Semecarpus kurzii: an ethnomedicinally important plant

摘要

Semecarpus kurzii Engl.is an important ethnomedicinal plant used for curing tumours,inflammation,fever and pain,and is also a source of iso ricinoleic acid.During the present investigation,effect of chemical pretreatments on germination and seedling growth revealed significant differences.Different pre-treatments could improve germination and treatment with KNO3 (9.9 mM) was significantly superior (94％) to the untreated control (76％).Mean daily germination varied among the treatments (0.90-4.14 seeds per day),when compared with 2.27 seeds per day in control.Mean germination time was significantly reduced from 22.14 days (control) to 16.40 days (19.8 mM KNO3) and 17.16 days (1.45 mM GA3).Treatment with KNO3 (19.8 mM) and GA3 (1.45 and 2.90 mM) significantly reduced the time for 50％ germination.Treatment with higher concentrations of GA3 and KNO3 exhibited significantly faster germination initiation (11.0and 12.0 days,respectively) over the control (17.0 days).Seedling vigour index was not improved by pre-treatments.Chemical treatments did not improve shoot growth,collar thickness,or number of seedling leaves;however,root growth was significantly improved over control.Treatment with GA3 (2.90 mM) promoted leaf elongation but reduced leaf width significantly.Treatment with KNO3 and GA3 could be recommended to obtain healthy seedlings for establishing new plantations of this important medicinal plant species.