| In this study,B.striata capsules collected from Shaanxi Liuba B.striata cultivation base were used as research materials,mainly studied the formation process of large number of B.striata seeds cultured by liquid stationary light to culture the protocorms,and the protocorms formed by culture were directly used in peat matrix and the process of seedling formation.Preliminary construction of a large number of B.striata seeds liquid stationary light culture,the protocorms direct seedling breeding technology.The effects of complete capsule and seed direct disinfection on seed germination rate,the difference of seedling formation of protocorms in sand and peat matrix and effects of different light intensities on seedling formation of protocorms were compared.In addition,the effects of 6-BA,NAA and 2,4-D on the occurrence of B.striata protocorm-like bodies were studied by using the protocorms formed by liquid culture for 40 days.The main results of this study are summarized as follows:1.A large number of B.striata seeds after sterilization,inoculation in the MS liquid medium under the light culture,after 5 d,the embryo obvious water swelling,the color turned to green,10 d,embryo break seed coat,the base of a small amount of false roots,leaf primordial uplift began to grow.45 d,when the second leaf,the protocorm base to form a large number of white fake roots.There was no significant difference in the seed germination rate between the untreated capsule and the direct disinfection of seeds.The protocorms can be seeded in the peat matrix,the leaves of the protocorms were grown on the peat,and the roots was formed after 20 d,the third leaf appeared at 30 d,the rooting rate was over 80% at 40 d,the pseudobulbe was formed at 70 d,the leaves died of aging,the buds on the pseudobulbe began to grow,the formation of transplantable seedlings after 100 d.Conclusion: A large number of B.striata seeds in the MS liquid medium under the light and standing culture,can be the normal development of the formation of protocorms,cultured for 45 days to form protocorms(about 1.7 mm in diameter)can be live in peat germinated and to form seedlings in 100 days.2.The effects of different light intensities on the formation of protocorms were significant.In the range of 550-2500 lx,the protocorms can form seedlings,but the fresh weight of the plant,the change of dry weight,the growth of leaf and root,the difference between root and form of pseudobulbe were significant;the stronger of the light,the greater fresh weight and dry weight of the seedlings,the higher incidence of root and pseudobulbes in the same period.Conclusion: B.striata protocorm can shoot in a wide range of light intensity.The higher the light intensity is,the better the seedling growth is in a certain range.3.The intact protocorms were inoculated with 6-BA,NAA and 2,4-D on the MS solid medium for 60 d,60 d of culture have the occurrence of PLBs,but the prevalence of protocorm formation,and in the absence of hormones on the medium without the occurrence of primitive PLBs.In the absence of hormone on the medium,the protocorms only show leaf growth;the incidence of PLBs was 42.42%(6-BA 2.0 mg/L+NAA 0.2 mg/L)in different concentrations of 6-BA and NAA,while in different concentrations of 6-BA and 2,4-D on the medium,the incidence of PLBs was as high as 51.28%(6-BA 3.0 mg/L+2,4-D 0.5 mg/L),the mortality of the protocorms up to 76.67%.Conclusion: The best induction medium was MS+6-BA 2.0 mg/L+NAA 0.2 mg/L,the incidence of PLBs was higher in this medium and the mortality of the protocorms was relatively low. |
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