Effects Of Different Impact Factors On Growth And Diosgenin Content Of Solanum Lyratum Thunb. Hairy Roots

Solanum lyratum is the plant of the genus Solanum L.(family Solanaceae).The main medicinal ingredients is diosgenin. The whole grass have functions of detoxification, dehumidification, anti-cancer, etc. The current research mainly on its chemical composition and pharmacological effects. The hairy root induction and culture of S. lyratum has not been reported. In this research, use Agrobacterium Rhizogenes C58C1 infect S. lyratum leaves to obtain the hairy roots. Then, in order to expand the hairy roots growth and improve the accumulation of the main medicinal ingredients, we studied the effects of 6-Benzylaminopurine(6-BA), α-Naphthaleneacetic(NAA) and colchicine on growth and diosgenin contents of S. lyratum hairy roots. At the same time,inducing hairy roots-plant regeneration. The main results were as follows:1. Use Agrobacterium Rhizogenes C58C1 infect S. lyratum leaves 10 minutes,After co-culture 4 days, light culture around 10 days, induce hairy roots. Hairy roots of S. lyratum in 1/2 MS liquid medium without plant growth substance grew faster, and showed no geotropism, more branch and densely root hair. According to experiments,the hairy root which was cultured in the liquid medium has several features: the growth of S. lyratum hairy root go into the logarithmic growth phase after culturing 12 d. When culture in about 36 d, the growth and the diosgenin contents of hairy roots reach a maximum.2. In order to study the effects of plant growth substance on the growth and diosgenin contents of S. lyratum hairy roots, we cultured the hairy roots with different concentrations of 6-BA, NAA alone or 6-BA in combination with NAA. The diosgeninof hairy roots were examined by high performance liquid chromatography(HPLC). The results showed that 6-BA inhibited the growth, and increased the hairy roots per gram of dry matter contents of diosgenin. But 6-BA decreased the content of total diosgenin.Furthermore, the inhibition was increased with the concentration of 6-BA. Low concentration of NAA promoted the growth and increased the content of total diosgenin.The hairy roots cultured with 0.5 mg·L-1 NAA after 30 d, the weight was 1.76 times of control, and the content of total diosgenin reached 0.97 mg(DW)·flask-1, it’s 1.37 times of maximum value of control. Different concentrations of 6-BA in combination with 0.5mg·L-1 NAA could inhibit the growth of hairy roots and decrease the content of total diosgenin. So we can culture the hairy roots with 0.5 mg·L-1 NAA to expand the hairy root growth and improve the content of diosgenin.3. Use different concentrations of colchicine treated the hairy roots to study the effects of colchicine on the growth and diosgenin contents of S. lyratum hairy roots. At the same time, inducing hairy roots-plant regeneration. The experimental results showed that, the colchicine promoted the growth of hairy root after treating 48 h, after 72 h, the growth of hairy roots was suppressed, and high concentration of colchicin treatment 24 h inhibited the growth. The growth of hairy roots treated with 0.3% colchicine for 24 h could be obviously increased, the biomass was 1.49 times of control. The contents of diosgenin reached a maximum by treating with 0.5% colchicine for 24 h. Overall, hairy roots treated with 0.3% colchicine for 24 h was beneficial for the growth and diosgenin contents of S. lyratum hairy roots. Compared with the control, the hairy roots regenerated plants showed shorter internodes, more epidermal hair, stem stout, and the size of guard cell were larger and the density of stomata was lower than control.